JP2022007938A - Base station and control method - Google Patents

Abstract

To contribute to the provision of a base station and a control method that can improve communication characteristics.SOLUTION: A base station includes a receiving unit that receives a first signal transmitted by a first terminal using a spread spectrum method and a second signal transmitted by a second terminal using a method different from the spread spectrum method, and a control unit that determines a channel to be assigned to the first terminal on the basis of information on the communication quality of the first signal, and determines a channel to be assigned to the second terminal on the basis of information on the communication quality of the second signal. The control unit switches the transmission power control of the first terminal according to the assignment status of the second terminal in the channel assigned to the first terminal.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to base stations and control methods.

A unlicensed band (unlicensed band) may be used for communication between wireless communication devices (for example, between a base station and a terminal). Unlicensed bands are used by various wireless communication systems.

For example, Patent Document 1 describes a wireless communication system that determines channel allocation so as to minimize the amount of interference when allocating channels used for communication to a plurality of base stations.

Japanese Unexamined Patent Publication No. 2013-81089

However, there is room for study on a method for improving communication characteristics in an environment used by various wireless communication systems.

The non-limiting examples of the present disclosure contribute to the provision of a base station capable of improving communication characteristics and a control method.

The base station according to the embodiment of the present disclosure includes a first signal transmitted by a first terminal using a spread spectrum method and a second signal transmitted by a second terminal using a method different from the spread spectrum method. Based on the information on the communication quality of the first signal and the receiving unit that receives the above, the channel to be assigned to the first terminal is determined, and the second signal is based on the information on the communication quality of the second signal. A control unit for determining a channel to be assigned to the second terminal is provided, and the control unit includes a control unit of the first terminal according to the allocation status of the second terminal in the channel assigned to the first terminal. Switch transmission power control.

The control method according to the embodiment of the present disclosure is a first signal transmitted by a first terminal using a spread spectrum method and a second signal transmitted by a second terminal using a method different from the spread spectrum method. Is received, the channel to be assigned to the first terminal is determined based on the information regarding the communication quality of the first signal, and the second terminal is determined based on the information regarding the communication quality of the second signal. The channel assigned to the first terminal is determined, and the transmission power control of the first terminal is switched according to the allocation status of the second terminal in the channel assigned to the first terminal.

It should be noted that these comprehensive or specific embodiments may be realized by a system, an apparatus, a method, an integrated circuit, a computer program, or a recording medium, and the system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium may be realized. It may be realized by any combination of.

According to one embodiment of the present disclosure, communication characteristics can be improved.

Further advantages and effects in one embodiment of the present disclosure will be apparent from the specification and drawings. Such advantages and / or effects are provided by some embodiments and the features described in the specification and drawings, respectively, but not all need to be provided in order to obtain one or more identical features. There is no.

The figure which shows the outline of the wireless system including LPWA. Block diagram showing a configuration example of a base station according to an embodiment The figure which shows the example of the classification process of the interference inside management and the interference outside management The figure which shows the 1st example of channel allocation and transmission power control. Flowchart of the first example of channel allocation and transmit power control Figure showing a second example of channel allocation and transmit power control Flowchart of the second example of channel allocation and transmit power control Flow chart executed in S202 of FIG. The figure which shows the 3rd example of channel allocation and transmission power control. Flowchart of the third example of channel allocation and transmit power control Figure showing a fourth example of channel allocation and transmit power control Flowchart of the fourth example of channel allocation and transmit power control Flow chart executed in S401 of FIG. Figure showing an example of variation 1-1 of channel allocation Flowchart of variation 1-1 of channel allocation Figure showing an example of variation 1-2 of channel allocation Flowchart of variation 1-2 of channel allocation Figure showing an example of variation 2 of channel allocation Flowchart of variation 2 of channel allocation Flow chart executed in S601 of FIG. Figure showing an example of variation 3 of channel allocation Flow chart executed in S601 of FIG. Figure showing an example of variation 4-1 of channel allocation Flowchart of variation 4 of channel allocation Flow chart corresponding to variation 4-1 executed in S806 of FIG. 24 Figure showing an example of variation 4-2 of channel allocation Flow chart corresponding to variation 4-2 executed in S806 of FIG. 24 Figure showing an example of variation 4-3 of channel allocation Flow chart corresponding to variation 4-3 executed in S806 of FIG. 24 Figure showing an example of variation 5-1 of channel allocation Flowchart example of variation 5-1 of channel allocation Figure showing an example of variation 5-2 of channel allocation An example of a flowchart corresponding to variation 5-2 executed in S806 of FIG. 24. Figure showing an example of variation 5-3 of channel allocation The figure which shows the example of the transmission power control for the channel allocation shown in FIG. An example of a flowchart relating to transmission power control shown in FIG. 35. The figure which shows the example of the transmission power control for the channel allocation shown in FIG. 32. An example of a flowchart relating to transmission power control shown in FIG. 37.

Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same function are designated by the same reference numerals, so that duplicate description will be omitted.

(One embodiment)
In IoT (Internet of Things) and / or M2M (Machine to Machine), the use of wireless communication technology called LPWA (Low Power Wide Area), which enables communication in a wide area with low power consumption, is being studied.

LPWA is being considered for operation in an unlicensed band (for example, 920 MHz band). There are a plurality of methods (standards) in LPWA. For example, the LPWA communication method includes a first communication method in which communication is performed using a spread spectrum method and a second communication method in which communication is performed without using a spread spectrum method. The first communication method includes, for example, a communication method called "LoRa". Further, the second communication method includes, for example, a communication method called "Wi-SUN (Wireless Smart Utility Network)".

In the following, as an example of the first communication method, a communication method called "LoRa" (hereinafter referred to as "LoRa method") will be mentioned, and as an example of the second communication method, it will be referred to as "Wi-SUN". The communication method to be used (hereinafter referred to as "Wi-SUN method") is listed. However, the present disclosure is not limited to the LoRa method and the Wi-SUN method.

Further, in the following, the terminal that operates based on the LoRa method (supports the LoRa method) is described as "LoRa terminal", and the terminal that operates based on the Wi-SUN method (supports the Wi-SUN method) is described as "LoRa terminal". , "Wi-SUN terminal". Further, the "LoRa terminal" and the "Wi-SUN terminal" may be described as an LPWA terminal or a terminal without distinction. Further, in the following, the signal transmitted / received based on the LoRa method is described as a “LoRa signal”, and the signal transmitted / received based on the Wi-SUN method is described as a “Wi-SUN signal”.

The LPWA terminal is not limited to the terminal owned by the user, but is mounted on various devices. For example, LPWA terminals are also mounted on televisions, air conditioners, washing machines, home appliances such as refrigerators, and mobile transportation such as vehicles.

In addition to LPWA, the unlicensed band is used by various systems including, for example, Wi-fi (registered trademark) and RFID (Radio Frequency IDentifier).

FIG. 1 is a diagram showing an outline of a wireless system including LPWA.

FIG. 1 shows group # 1, group # 2, and group # 3. Each group contains multiple devices.

Groups # 1 and # 2 are both LPWA systems. However, the network # 1 (NW # 1) to which each device of the group # 1 belongs is different from the network # 2 (NW # 2) to which each device of the group # 2 belongs. For example, NW # 1 and NW # 2 are the same LPWA system and are networks operated by different operators. The LPWA system of group # 2 is a wireless system of a network (unmanaged network) not managed by group # 1.

Group # 1 includes devices belonging to NW # 1 and having a wired or wireless connection with NW # 1. For example, group # 1 includes base station # 1, Wi-SUN terminal # 1, LoRa terminal # 1, and LoRa terminal # 2. Further, the group # 1 includes a control device # 1 that centrally controls the GW and the like via the NW # 1.

Base station # 1 may have a gateway (GW) function and a radio wave monitoring function. For example, the GW function of base station # 1 may support both the Wi-SUN system and the LoRa system. The Wi-SUN terminal # 1, the LoRa terminal # 1, and the LoRa terminal # 2 may be wirelessly connected to the base station # 1 to transmit and receive signals.

Group # 2 includes devices belonging to NW # 2 and having a wired or wireless connection with NW # 2. For example, group # 2 includes base station # 2, Wi-SUN terminal # 2, LoRa terminal # 3, and LoRa terminal # 4. Further, the group # 2 includes a control device # 2 that centrally controls the GW and the like via the NW # 2.

Base station # 2 may have a GW function and a radio wave monitoring function. For example, the GW function of base station # 2 may support both the Wi-SUN system and the LoRa system. The Wi-SUN terminal # 2, the LoRa terminal # 3, and the LoRa terminal # 4 may be wirelessly connected to the base station # 2 to transmit and receive signals.

The number of devices in groups # 1 and group # 2 in FIG. 1 is an example, and the present disclosure is not limited to this. For example, the number of base stations included in groups # 1 and group # 2 in FIG. 1 may be 2 or more. The number of LPWA terminals included in the group # 1 and the group # 2 in FIG. 1 may be 4 or more, or may be 2 or less. Further, other devices may be connected to the NW of each group.

Further, the group # 1 may include a relay station that relays wireless communication between the base station # 1 and any of the terminals. A similar relay station may be included in group # 2.

Group # 3 is a wireless system different from the wireless system (LPWA system) of group # 1. The radio system of group # 3 is a radio system of an unmanaged network that is not managed by group # 1. Group # 3 wireless systems are, for example, RFID and Wi-fi. Group # 3 includes RFID readers / writers, RFID tags, terminals using Wi-fi, and the like. The wireless system of group # 3 may include an LTE (Long Term Evolution) system, a radar system, and the like.

The network configuration shown in FIG. 1 and / or the configuration of the device is an example, and the present disclosure is not limited to this.

For example, FIG. 1 shows an example in which the LoRa terminal and the Wi-SUN terminal are separate terminals, but the terminal may be operable based on both the LoRa method and the Wi-SUN method.

Further, in the above description, the base station # 1 and the base station # 2 have shown an example having a GW that supports both the Wi-SUN system and the LoRa system, but the GW and the LoRa system that support the Wi-SUN system are used. It may be a device different from the supporting GW. Further, the device for performing radio wave monitoring may be a device different from the base station.

Further, for example, two or more of the Wi-SUN gateway, the LoRa gateway, the radio wave monitoring device, and the control device may be integrated.

Further, each network shown in FIG. 1 may include a device different from the device shown in FIG. In that case, the other device may have some or all of the functions of the device shown in FIG. For example, when a relay station is provided between a base station and a Wi-SUN terminal and / or a LoRa terminal, the relay station may have a function of a radio wave monitoring device. Further, the relay station may have the functions of the gateway of Wi-SUN and / or the gateway of LoRa and the function of the radio wave monitoring device. Alternatively, the relay station may have the function of a radio wave monitoring device and may not have the function of a gateway of Wi-SUN and / or a gateway of LoRa.

Each radio device of groups # 1 to # 3 uses a common system band (for example, an unlicensed band). Therefore, each wireless device included in the groups # 1 to # 3 receives interference from other wireless devices. The interference received by the wireless devices included in group # 1 will be described as an example.

For example, a signal transmitted or received by a radio device included in group # 1 (eg, LoRa terminal # 2) causes interference in another radio device included in group # 1 (eg, LoRa terminal # 1). .. In the following, the interference that a radio device belonging to NW # 1 receives from another radio device belonging to NW # 1 may be described as "interference within management". For example, intra-managed interference corresponds to interference that a radio device belonging to NW # 1 supports communication of an LPWA system and receives communication from another radio device belonging to NW # 1.

Further, a terminal (for example, LoRa terminal # 2) belonging to the same NW as a certain base station (for example, base station # 1) and a certain terminal (for example, LoRa terminal # 1) is a certain base station and a certain terminal. It may be described as "managed terminal" for the terminal. The in-management terminal may be a terminal that may transmit a signal that causes in-management interference. Further, the LoRa terminal and the Wi-SUN terminal which are the managed terminals may be described as "the managed LoRa terminal" and "the managed Wi-SUN terminal", respectively.

Also, for example, a signal transmitted or received by a radio device included in group # 2 and / or group # 3 (eg, LoRa terminal # 3 and / or RFID reader / writer) is a radio device included in group # 1. (For example, LoRa terminal # 1) causes interference. In the following, the interference that a radio device belonging to NW # 1 receives from a radio device not belonging to NW # 1 may be described as "unmanaged interference". For example, unmanaged interference supports communication in an LPWA system and corresponds to interference received by a radio device belonging to NW # 1 from a radio device not belonging to NW # 1.

Further, a terminal (for example, LoRa terminal # 3) belonging to a NW different from a certain base station (for example, base station # 1) and a certain terminal (for example, LoRa terminal # 1) is a certain base station and a certain terminal. May be described as "unmanaged terminal". The unmanaged terminal may be a terminal that may transmit a signal that causes unmanaged interference. Further, the LoRa terminal and the Wi-SUN terminal, which are unmanaged terminals, may be described as "unmanaged LoRa terminal" and "unmanaged Wi-SUN terminal", respectively.

Uncontrolled interference is further classified based on the cause of the interference.

For example, a signal transmitted or received by a radio device included in group # 2 (eg, LoRa terminal # 3) causes interference in the radio device included in group # 1 (eg, LoRa terminal # 1). In the following, the interference that the radio device belonging to NW # 1 receives from the radio device belonging to NW # 2 may be described as "radio wave interference" among "unmanaged interference". For example, "radio wave interference" corresponds to interference that a radio device belonging to NW # 1 supports communication of an LPWA system and supports communication of an LPWA system and receives from a radio device belonging to NW # 2 different from NW # 1. do.

Also, for example, a signal transmitted or received by a wireless device (eg, RFID reader / writer) included in group # 3 causes interference in the wireless device (eg, LoRa terminal # 1) included in group # 1. .. In the following, the interference that a wireless device belonging to NW # 1 that supports communication of an LPWA system receives from a wireless device that supports a wireless system different from the LPWA system is described as "environmental noise" among "unmanaged interference". May be done.

As shown by taking FIG. 1 as an example, the LPWA system uses a common system band with a radio system different from the LPWA system and / or the same LPWA system belonging to a different network. Therefore, in the LPWA system, it is desired to detect (monitor) the interference and use the detected result to improve the efficiency (for example, frequency utilization efficiency) and / or the communication quality (communication characteristic) in the LPWA system.

For example, the communication method supported by the LPWA system includes the above-mentioned Wi-SUN method and LoRa method.

In the LoRa method, a parameter called Spreading Factor (hereinafter, SF) is defined. SF indicates the ratio of the spreading code speed (chip rate) to the transmission data speed (bit rate) when wireless communication is performed by the spread spectrum method. In the LoRa method, the SF value is set from, for example, ⁶ levels of values from ²⁷ to 212.

^In the following, the SF values set in the six levels of ²⁷ to 212 are described as SF7 to SF12, respectively. For example, a transmission signal transmitted using the spread spectrum method in which the SF value is set to 27 may be described as a transmission signal using SF ⁷ .

For example, in the LoRa method, the larger the SF value, the higher the resistance to communication noise and interference, and the longer the communicable distance. On the other hand, the larger the SF value, the longer the time (signal length) required to transmit data of the same size. Therefore, the larger the SF value, the higher the frequency of interference with other terminals and the frequency of interference from other terminals.

Further, in the LoRa method, the resistance when the LoRa signal collides differs depending on the value of SF. For example, two LoRa signals transmitted using different SF values have a diffusion gain in reception processing (for example, reverse diffusion processing) even if some or all of them overlap in the same time. Easy to obtain. On the other hand, if two LoRa signals transmitted using the same SF value are partially or wholly overlapped within the same time, the two LoRa signals transmitted using different SF values are used. Compared with the case of, it is difficult to obtain a diffusion gain in the reception process (for example, the back diffusion process).

In a wireless system including LPWA, the base station allocates a channel to a terminal (in-managed terminal) under the base station, and the in-managed terminal uses the LoRa method and / or the Wi-SUN method in the assigned channel. Send a signal. In the channel assigned to the managed terminal, since the managed terminal and / or the unmanaged terminal different from the managed terminal transmits a signal, interference may occur and the communication characteristics may be deteriorated.

Therefore, in the LPWA system, it is considered to control the transmission power of the LoRa terminal using the spread spectrum method.

For example, in group # 1, base station # 1 receives a signal transmitted by a managed LoRa terminal (eg, LoRa terminal # 1), measures received power (eg, Received Signal Strength Indicator (RSSI)), and measures it. The measured received power is output to the NW (for example, control device # 1). The control device # 1 determines the transmission power of the managed LoRa terminal based on the received power. The managed LoRa terminal acquires the determined transmission power information via the base station # 1 and performs signal transmission.

However, in a situation where a plurality of wireless devices including the managed LoRa terminal use the same channel, the above control of transmission power may not be sufficient. Therefore, it is desired to improve the communication characteristics by performing appropriate transmission power control according to the allocation status in the channel.

Therefore, the non-limiting examples of the present disclosure contribute to the provision of terminals, base stations, and control methods capable of improving communication characteristics.

The wireless communication system according to the present embodiment includes the base station 100 shown in FIG. 2 and the terminals under the base station 100. The base station 100 and the terminal are included in, for example, an LPWA wireless communication system. For example, the base station 100 supports both the LoRa system and the Wi-SUN system.

<Base station configuration>
FIG. 2 is a block diagram showing a configuration example of the base station 100 according to the present embodiment. The base station 100 includes a receiving unit 101, a despreading unit 102, a communication quality measuring unit 103, a preamble detection unit 104, an interference classification unit 105, an SF selection unit 106, a demodulation / decoding unit 107, and a despreading unit. Unit 108, SF extraction unit 109, SF allocation unit 110, allocation control unit 111, control method selection unit 112, transmission power setting unit 113, control signal generation unit 114, and coding / modulation unit 115. , And a transmission unit 116. For example, the reverse diffusion unit 102, the communication quality measurement unit 103, the preamble detection unit 104, the interference classification unit 105, the SF selection unit 106, the demodulation / decoding unit 107, the reverse diffusion unit 108, and the SF extraction unit 109. , SF allocation unit 110, allocation control unit 111, control method selection unit 112, transmission power setting unit 113, control signal generation unit 114, and part or all of the coding / modulation unit 115. It may be called a "control unit".

The receiving unit 101 receives the signal transmitted by the terminal, and performs a predetermined reception process on the received signal. For example, the predetermined reception process includes a frequency conversion process (down-conversion) based on the frequency of the channel assigned to the terminal. Information on the frequency of the channel assigned to the terminal may be acquired from, for example, the allocation control unit 111.

Further, the receiving unit 101 receives a signal in each available channel (for example, each channel included in the unlicensed band) for interference measurement (radio wave monitoring). Then, the receiving unit 101 performs a predetermined reception process on the received signal. The predetermined reception process includes, for example, a frequency conversion process based on the frequency of each channel.

The receiving unit 101 outputs the received signal that has undergone the predetermined reception processing to the despreading unit 102, the communication quality measuring unit 103, the preamble detection unit 104, and the despreading unit 108.

The despreading unit 102 performs despreading processing on the LoRa signal included in the received signal acquired from the receiving unit 101. The despreading unit 102 may perform backspreading processing for each of the SF values that can be used between the base station 100 and the terminal, for example. The back-diffusion unit 102 outputs the result of the back-diffusion process to the SF selection unit 106.

The SF selection unit 106 determines the SF value used for the LoRa signal based on the result of the back diffusion processing. For example, the SF selection unit 106 sets the SF value corresponding to the result of the back diffusion processing in which a peak occurs in the result of the back diffusion processing of the LoRa signal for each of the available SF values as the SF value used for the LoRa signal. Decide that there is. The SF selection unit 106 outputs the determined SF value and the result of the back diffusion processing to the demodulation / decoding unit 107.

For the Wi-SUN signal included in the received signal, the back diffusion process and the SF value selection need not be performed.

The demodulation / decoding unit 107 performs demodulation processing and decoding processing of the LoRa signal based on the SF value acquired from the SF selection unit 106 and the result of the back diffusion processing, and generates received data. Further, the demodulation / decoding unit 107 performs demodulation processing and decoding processing of the Wi-SUN signal included in the received signal to generate received data. The demodulation / decoding unit 107 outputs the received data to the allocation control unit 111. The received data may include an identifier that identifies a terminal that belongs to the same NW (Network) as the base station 100.

The communication quality measuring unit 103 generates communication quality information based on the received signal acquired from the receiving unit 101. The communication quality information may be, for example, the quality of the received signal (eg, Received Signal Strength Indicator (RSSI)). The communication quality measuring unit 103 outputs the communication quality information to the allocation control unit 111.

The preamble detection unit 104 detects whether or not the reception signal acquired from the reception unit 101 includes a preamble. Further, when the preamble is included, the preamble detection unit 104 determines the type of the preamble included in the received signal.

For example, the preamble detection unit 104 calculates the correlation between the preamble used in the LoRa method and the received signal. The preamble detection unit 104 determines that the preamble used in the LoRa method is included in the received signal when a peak of a predetermined value or more occurs in the calculated correlation result. When the preamble used in the LoRa method is included in the received signal, it is determined that the received signal is a LoRa signal and the source of the signal is a LoRa terminal.

Similar to the example of the LoRa method, the preamble detection unit 104 calculates the correlation between the preamble used in the Wi-SUN method and the received signal. When the calculated correlation has a peak of a predetermined value or more, the preamble detection unit 104 determines that the preamble used in the Wi-SUN method is included in the received signal. When the preamble used in the Wi-SUN system is included in the received signal, it is determined that the received signal is a Wi-SUN signal and the source of the received signal is a Wi-SUN terminal.

The preamble detection unit 104 detects the preamble regardless of whether or not the source of the received signal is included in the NW to which the base station 100 belongs. In other words, the preamble detection unit 104 may determine the type of preamble included in the signal transmitted by the LoRa terminal and the Wi-SUN terminal that are not included in the NW to which the base station 100 belongs.

Further, the preamble detection unit 104 has a peak of a predetermined value or more in both the result of the correlation between the preamble used in the LoRa method and the received signal and the result of the correlation between the preamble used in the Wi-SUN method and the received signal. If the above does not occur, it is determined that the source of the received signal is neither the LoRa terminal nor the Wi-SUN terminal.

The preamble detection unit 104 outputs to the interference classification unit 105 information indicating whether or not the received signal contains a preamble, and if the preamble is included in the received signal, information indicating the type of the preamble. do. Further, the preamble detection unit 104 outputs the reception signal acquired from the reception unit 101 to the interference classification unit 105.

The interference classification unit 105 classifies the interference in each channel, for example. For example, the interference classification unit 105 monitors and classifies received signals at a predetermined time in one channel. For example, the interference classification unit 105 may determine the difference between the transmission sources of the received signals within a predetermined time. The interference classification unit 105 calculates the ratio of the time of the received signal for each transmission source to the predetermined time, and classifies the interference in each channel. For example, the interference classification unit 105 may classify the sources of signals that cause dominant interference in the interference of each channel. Here, in each channel, the dominant interference may correspond to, for example, that, as a result of monitoring the received signal for a predetermined time, the ratio of time to the predetermined time is equal to or more than the predetermined ratio.

The interference classification unit 105 outputs the interference classification result in each channel to the allocation control unit 111.

The despreading unit 108 performs despreading processing on the received signal acquired from the receiving unit 101. The despreading unit 108 may perform backspreading processing for each of the SF values that can be used between the base station 100 and the terminal, for example. The back-diffusion unit 108 outputs the result of the back-diffusion process to the SF extraction unit 109.

The SF extraction unit 109 detects the SF value used for the LoRa signal from the result of the back diffusion processing. For example, the SF extraction unit 109 determines an SF value excluding the SF value used for the LoRa signal, that is, an unused SF value among the available SF values. Alternatively, the SF extraction unit 109 may determine the frequency of the SF value used for the LoRa signal. The frequency of use of the SF value may be represented by the number of times the SF value is detected. For example, the unused SF value may be an SF value whose frequency of use (number of detections) is 0. The SF extraction unit 109 outputs the determined unused SF value and / or information regarding the frequency of use of the SF value to the SF allocation unit 110.

The SF allocation unit 110 allocates SF values to LoRa terminals under the base station 100 based on the information acquired from the SF extraction unit 109. For example, the SF allocation unit 110 allocates any one of unused SF values to the terminal. When a plurality of unused SF values exist, the SF allocation unit 110 may allocate the smallest SF value among the plurality of unused SF values to the terminal. Alternatively, in this case, the SF allocation unit 110 may allocate a randomly selected SF value among a plurality of unused SF values to the terminal. The SF allocation unit 110 outputs information indicating the SF value to be allocated to the allocation control unit 111.

The allocation control unit 111 determines a channel to be allocated to the terminal based on the communication quality information (for example, information indicating received power such as RSSI) acquired from the communication quality measurement unit 103. The allocation control unit 111 may determine the channel to be allocated to the terminal based on the communication quality information and the interference classification result acquired from the interference classification unit 105.

The allocation control unit 111 outputs information (channel allocation information) regarding the channel allocated to the terminal to the control method selection unit 112. Further, the allocation control unit 111 outputs information regarding the determination of the transmission power of the terminal to the control method selection unit 112. The information regarding the determination of the transmission power of the terminal includes, for example, information indicating the reception power of the signal transmitted from the terminal at the base station 100. In addition, the information regarding the determination of the transmission power of the terminal may include the classification result of the interference in each channel.

Further, the allocation control unit 111 controls data communication with the terminal. For example, the received data acquired from the demodulation / decoding unit 107 may be output to a higher-level station (not shown) or another device in the network (for example, a control device (see FIG. 1)). Further, the allocation control unit 111 outputs the transmission data addressed to the terminal acquired from the host station or another device in the network to the coding / modulation unit 115. The transmission data addressed to the terminal may include an identifier indicating the destination.

The control method selection unit 112 selects a method (transmission power control method) for controlling the transmission power of the terminal based on the channel allocation information and the information indicating the received power. The control method selection unit 112 outputs the selection result to the transmission power setting unit 113.

The transmission power setting unit 113 sets the transmission power of the terminal based on the selection result. The transmission power setting unit 113 stores the transmission power of the set terminal. The transmission power setting unit 113 outputs the transmission power and channel allocation information of the set terminal to the control signal generation unit 114.

The control signal generation unit 114 generates a control signal addressed to the terminal based on the information acquired from the transmission power setting unit 113. The control signal generation unit 114 outputs a control signal subjected to predetermined signal processing (for example, coding processing and modulation processing) to the transmission unit 116.

The coding / modulation unit 115 performs coding processing and modulation processing on the transmission data acquired from the allocation control unit 111 to generate a transmission signal. The coding / modulation unit 115 outputs the transmission signal to the transmission unit 116. When the terminal to which the transmission signal is transmitted is a LoRa terminal, the modulation processing may include the spread spectrum processing used in the LoRa method. Further, in the spread spectrum processing, the SF value assigned to the LoRa terminal may be used.

The transmission unit 116 performs a predetermined transmission process on the transmission signal acquired from the coding / modulation unit 115. For example, the predetermined transmission process includes a frequency conversion process (up-conversion) based on the frequency of the channel assigned to the terminal. Information on the frequency of the channel assigned to the terminal may be acquired from, for example, the allocation control unit 111.

Further, the transmission unit 116 performs a predetermined transmission process on the control signal acquired from the control signal generation unit 114. For example, the predetermined transmission process includes a frequency conversion process (up-conversion) based on the frequency of the channel for transmitting the control signal to the terminal. The channel for transmitting the control signal to the terminal may be, for example, a predetermined channel or a channel currently used for communication with the terminal.

In the above description, an example in which the configuration shown in FIG. 2 is included in one base station 100 has been described. The present disclosure is not limited to this. For example, any one of the two or more devices may include each of the configurations shown in FIG.

<Example of classification process>
Next, an example of the classification process in the interference classification unit 105 will be described. A classification process for classifying the signal (interference) received by the receiving unit 101 into intra-managed interference and unmanaged interference will be described.

<Example of classification processing between in-management interference and out-of-management interference>
FIG. 3 is a diagram showing an example of classification processing between in-control interference and out-of-control interference. The horizontal axis of FIG. 3 indicates a time axis. FIG. 3 shows the signal level of the received signal in a predetermined monitoring section, the detection result of interference with the received signal, the detection result of the identifier (terminal ID) of the terminal, and the determination result.

The detection result of interference with the received signal corresponds to, for example, the detection result by preamble detection. Based on this result, the LoRa signal included in the received signal is determined.

In the detection result of the terminal identifier (terminal ID), when the identifier is obtained by the demodulation / decoding process for the received signal, the terminal ID indicates "OK". When the terminal ID indicates "OK", it is determined that the NW to which the source of the received signal belongs is the same NW as the base station 100. In other words, as shown in the determination result, it is determined that the received signal corresponds to the interference within the management.

In the detection result of the terminal identifier (terminal ID), if the identifier cannot be obtained by the demodulation / decoding process for the received signal, the terminal ID indicates "NG". When the terminal ID indicates "NG", it is determined that the NW to which the source of the received signal belongs is a NW different from that of the base station 100. In other words, as shown in the determination result, it is determined that the received signal corresponds to unmanaged interference.

By the above classification process, it is classified whether the received signal corresponds to the interference within the control or the interference outside the control.

Next, the channel allocation performed by the base station 100 and the transmission power control of the terminal will be described with reference to examples.

<First example of channel allocation and transmission power control>
FIG. 4 is a diagram showing a first example of channel allocation and transmission power control.

The horizontal axis of FIG. 4 shows the frequency, and the vertical axis shows the usage level of each channel. FIG. 4 shows the level of usage between the managed terminal and the unmanaged terminal in each of the channels # 24 to channel # 60 with the identification number. In FIG. 4, channels # 24 to channel # 32 are LoRa channels, channels # 33 to channel # 38 are shared channels, and channels # 39 to channel # 60 are Wi-SUN channels. Further, the usage level in FIG. 4 is defined based on the number of assigned terminals and the transmission probability of the assigned terminals. For example, the larger the number of assigned terminals, the higher the usage status level, and the higher the transmission probability of the assigned terminals, the higher the usage status level.

The managed LoRa terminal is assigned to the LoRa channel and the shared channel. Further, the managed Wi-SUN terminal is assigned to the Wi-SUN channel and the shared channel. In other words, the LoRa channel corresponds to a channel to which the managed LoRa terminal is assigned and the managed Wi-SUN terminal is not assigned. The Wi-SUN channel corresponds to a channel to which the managed Wi-SUN terminal is assigned and the managed LoRa terminal is not assigned. The shared channel corresponds to the channel to which the managed LoRa terminal and the managed Wi-SUN terminal are assigned. The LoRa channel and the Wi-SUN channel may be referred to as non-shared channels.

In this embodiment, an example is shown in which an unmanaged LoRa terminal is assigned and an unmanaged Wi-SUN terminal is not assigned in the LoRa channel. In this case, the LoRa channel may be referred to as, for example, a LoRa dedicated channel. However, in the present disclosure, the LoRa channel does not have to be a LoRa dedicated channel. For example, an unmanaged Wi-SUN terminal may be assigned to the LoRa channel.

In this embodiment, an example is shown in which an unmanaged Wi-SUN terminal is assigned and an unmanaged LoRa terminal is not assigned in the Wi-SUN channel. In this case, the Wi-SUN channel may be referred to as, for example, a Wi-SUN dedicated channel. However, in the present disclosure, the Wi-SUN channel does not have to be a Wi-SUN dedicated channel. For example, an unmanaged LoRa terminal may be assigned to the Wi-SUN channel.

The base station 100 receives the signal transmitted by each managed terminal and determines the received power. Then, the base station 100 allocates channels based on the received power of the signal transmitted by each managed terminal.

In the following, the received power determined by the base station 100 may be described as "GW received power". For example, the received power determined by the base station 100 by receiving the signal transmitted by a certain terminal x may be described as "GW received power of the terminal x". Further, the terminal x of the transmission source of the signal indicating a certain GW received power may be described as "the terminal x corresponding to the GW received power".

Further, among the GW received power determined by receiving the signals transmitted by each of the plurality of terminals, the terminal x of the source of the signal showing the relatively large GW received power has "GW received power is relative". May be described as "large terminal x".

The signal received by the base station 100 may be a signal transmitted by the terminal on the channel after the base station 100 assigns a channel to the terminal. Alternatively, the signal received by the base station 100 may be a signal (eg, control signal, synchronization signal, etc.) transmitted by the terminal on a particular channel before the base station 100 allocates a channel to the terminal.

In FIG. 4, the base station 100 allocates the managed LoRa terminal having a relatively small GW reception power to the LoRa channel among the managed LoRa terminals to be allocated. Further, the base station 100 allocates the managed LoRa terminal having a relatively large GW reception power to the shared channel among the managed LoRa terminals to be allocated.

For example, the base station 100 compares the GW received power with the threshold value, allocates the managed LoRa terminal corresponding to the GW received power below the threshold value to the LoRa channel, and allocates the managed LoRa terminal corresponding to the GW received power larger than the threshold value to the LoRa channel. May be assigned to a shared channel. The threshold value may be fixed or set according to the usage status of the LoRa channel and the shared channel (for example, the number of assigned terminals and / or the transmission probability of each terminal). good.

Alternatively, the base station 100 may assign the managed LoRa terminal corresponding to the GW received power to the LoRa channel in order from the smallest GW received power. In this case, when the number of managed LoRa terminals assigned to the LoRa channel exceeds the specified value, the remaining managed LoRa terminals may be assigned to the shared channel. For example, the specified value may be fixed or set according to the usage status of the LoRa channel and the shared channel (for example, the number of assigned terminals and / or the transmission probability of each terminal). It's okay.

Alternatively, the base station 100 may allocate the managed LoRa terminals corresponding to the GW received power to the shared channel in order from the one having the largest GW received power. In this case, when the number of managed LoRa terminals assigned to the shared channel exceeds the specified value, the remaining managed LoRa terminals may be assigned to the LoRa channel. For example, the specified value may be fixed or set according to the usage status of the LoRa channel and the shared channel (for example, the number of assigned terminals and / or the transmission probability of each terminal). It's okay.

Further, for example, the base station 100 allocates the managed Wi-SUN terminal, which has a relatively small GW reception power, to the Wi-SUN channel among the managed Wi-SUN terminals to be allocated. Further, the base station 100 allocates the managed Wi-SUN terminal, which has a relatively large GW reception power, to the shared channel among the managed Wi-SUN terminals to be allocated.

The method for determining the managed Wi-SUN terminal to be assigned to the Wi-SUN channel and the shared channel may be the same as in the case of the managed LoRa terminal described above. For example, the managed Wi-SUN terminal to be assigned to each channel may be determined by comparing the GW received power with the threshold value, or the managed Wi-SUN terminal to be assigned to each channel may be determined in order from the smallest GW received power. Alternatively, the managed Wi-SUN terminal to be assigned to each channel may be determined in order from the one having the largest GW received power.

The base station 100 allocates a channel based on the received power of the signal transmitted by each managed terminal (GW received power of each managed terminal), and controls the transmission power of the managed LoRa terminal assigned to the shared channel. Here, in FIG. 4, the transmission power control for the managed LoRa terminal assigned to the shared channel may be described as “first transmission power control”. In other words, in FIG. 4, the base station 100 performs the first transmission power control (first transmission power control: ON) for the managed LoRa terminal assigned to the shared channel, and is in the management assigned to the LoRa channel. The first transmission power control is not performed on the LoRa terminal (first transmission power control: OFF). Hereinafter, an example of the first transmission power control for a certain terminal x assigned to a certain channel c will be described.

式（１）において、Ｔｘｐｏｗ_ｎｅｘｔは、第１送信電力制御後の端末ｘの送信電力を示し、Ｔｘｐｏｗ_ｎｏｗは、現時点での端末ｘの送信電力を示す。別言すると、第１送信電力制御において、基地局１００は、現時点（第１送信電力制御前）の端末ｘの送信電力Ｔｘｐｏｗ_ｎｏｗに、以下に説明する係数を乗算することによって、第１送信電力制御後の端末ｘの送信電力Ｔｘｐｏｗ_ｎｅｘｔを決定する。 <Example of first transmission power control>
The first transmission power control is performed using, for example, the equation (1).

In the formula (1), Txpow _next indicates the transmission power of the terminal x after the first transmission power control, and Txpow _now indicates the transmission power of the terminal x at the present time. In other words, in the first transmission power control, the base station 100 multiplies the transmission power Txpow _now of the terminal x at the present time (before the first transmission power control) by the coefficient described below to obtain the first transmission power. The transmission power Txpow _next of the terminal x after control is determined.

The RSSI of the formula (1) indicates the received power calculated by the base station 100 receiving the signal transmitted from the terminal x before the first transmission power control.

Α in the equation (1) is a coefficient determined by the communication method. α may be a coefficient for SINR difference correction of the LoRa method and the Wi-SUN method. α is set to a value within the range of the required SINR of both the LoRa method and the Wi-SUN method. If either the LoRa method or the Wi-SUN method is used in the channel c and the other is not used, the difference in SINR may not be corrected. If the difference in SINR is not corrected, α may be 1.

Further, the target of the equation (1) indicates the target value of the GW received power. For example, the target value may be the GW reception power of the signal transmitted by the Wi-SUN terminal having the longest distance from the base station 100 with the maximum transmission power. The target value may be set independently for each channel. The target value in a certain channel c may be set based on the GW received power of the managed Wi-SUN terminal assigned to the channel c. The target value in the channel c may be the smallest GW received power among the GW received powers of the managed Wi-SUN terminals assigned to the channel c.

For example, in FIG. 4, the base station 100 allocates a managed Wi-SUN terminal having a relatively large GW received power to a shared channel. Therefore, when performing the first transmission power control in the shared channel, the base station 100 may set the target value in the shared channel to a relatively high value. For example, the base station 100 may be set to a value higher than the smallest GW reception power among the managed Wi-SUN terminals to be allocated.

In the first transmission power control, the base station 100 determines the transmission power Txpow _next of the terminal x using the equation (1), and notifies the terminal x of the determined transmission power Txpow _next . The terminal x transmits a signal at the transmission power Txpow _next notified from the base station 100.

As shown in FIG. 4, by performing allocation based on GW received power and transmission power control for the managed LoRa terminal allocated to the shared channel, for example, deterioration of the communication characteristics of the managed Wi-SUN terminal can be suppressed and managed. The communication characteristics of the inner LoRa terminal can be improved.

<Flow of the first example of channel allocation and transmission power control>
FIG. 5 is a flowchart of a first example of channel allocation and transmission power control. For example, the flowchart shown in FIG. 5 may be started at predetermined time intervals.

The base station 100 measures the interference (S101).

The base station 100 determines whether or not the allocation of the channel to the subordinate terminal is completed (S102).

When the allocation is not completed (NO in S102), that is, when there is a terminal whose allocation process has not been completed (hereinafter referred to as "terminal z") among the terminals to be allocated, the base station 100 Executes the allocation process after S103 for the terminal z. On the other hand, when the allocation process is completed (YES in S102), that is, when there is no terminal whose allocation process has not been completed among the terminals to be allocated, the flow shown in FIG. 5 is terminated.

The base station 100 determines whether or not the communication method used by the terminal z is the Wi-SUN method (S103).

When the communication method used by the terminal z is Wi-SUN (YES in S103), the base station 100 determines whether or not the GW received power of the terminal z is larger than the first threshold value (S104).

When the GW received power of the terminal z is larger than the first threshold value (YES in S104), the base station 100 allocates the terminal z to the shared channel (S105). Then, the process of S102 is executed.

When the GW reception power of the terminal z is not larger than the first threshold value (NO in S104), the base station 100 allocates the terminal z to the Wi-SUN channel (S106). Then, the process of S102 is executed.

When the communication method used by the terminal z is not Wi-SUN (NO in S103), that is, when the communication method used by the terminal z is LoRa, the base station 100 has a second GW reception power of the terminal z. It is determined whether or not it is larger than the threshold value (S107).

When the GW received power of the terminal z is larger than the second threshold value (YES in S107), the base station 100 allocates the terminal z to the shared channel (S108). Then, the base station 100 performs the first transmission power control with respect to the terminal z (first transmission power control: ON) (S109). In the first transmission power control here, as illustrated in FIG. 4, the target value (target of the equation (1)) may be set to a relatively high value. Then, the process of S102 is executed.

When the GW reception power of the terminal z is not larger than the second threshold value (NO in S107), the base station 100 allocates the terminal z to the LoRa channel (S110). Then, the base station 100 does not perform the first transmission power control with respect to the terminal z (first transmission power control: OFF) (S111). Then, the process of S102 is executed.

As described above, in the first example, by performing the allocation based on the GW received power and the transmission power control for the managed LoRa terminal allocated to the shared channel, for example, the communication characteristics of the managed Wi-SUN terminal are deteriorated. Can be suppressed, and the communication characteristics of the managed LoRa terminal can be improved.

Note that FIG. 4 described above shows an example in which the usage conditions of the shared channels channels # 33 to # 38 are the same as each other, but the present disclosure is not limited to this. For example, the usage status of channels # 33 to channel # 38 may be different from each other. In this case, the transmission power determined in the first transmission power control may be different for each channel. For example, when the GW reception power of the Wi-SUN terminal in management differs for each channel, the target of the equation (1) is determined for each channel.

<Second example of channel allocation and transmission power control>
In the second example, the transmission power control for the managed LoRa terminal assigned to the LoRa channel will be described.

FIG. 6 is a diagram showing a second example of channel allocation and transmission power control. The horizontal axis and the vertical axis of FIG. 6 are the same as those of FIG. Further, since the allocation of the managed terminal to each channel and the transmission power control in the shared channel are the same as those in the first example shown in FIG. 4, the description thereof will be omitted.

In FIG. 6, the transmission power control method is selected from A and B for the managed LoRa terminal assigned to the LoRa channel. A is an option of not performing the first transmission power control, and B is an option of performing the first transmission power control. Since the Wi-SUN terminal in management is not assigned to the LoRa channel, it is not necessary to consider the SINR difference correction coefficient described above in the first transmission power control of B. That is, when the first transmission power control of B is performed, α = 1 may be set in the equation (1).

For example, the base station 100 may adaptively select either A or B based on the result of environmental monitoring. The base station 100 may select B if uncontrolled interference is dominant as a result of environmental monitoring on the LoRa channel, and select A if intra-managed interference is not dominant. For example, if the amount of interference of unmanaged interference is larger than the amount of interference of in-controlled interference, it may be determined that unmanaged interference is dominant. Further, for example, when the interference amount of the out-of-control interference is equal to or less than the interference amount of the in-control interference, it may be determined that the in-control interference is dominant. Alternatively, it may be determined that the interference showing the interference amount equal to or more than the threshold value is dominant among the interference amount of the interference within the control and the interference amount of the interference outside the control.

As shown in FIG. 6, the communication characteristics of the managed LoRa terminal can be improved by controlling the transmission power of the managed LoRa terminal assigned to the LoRa channel based on the result of the environmental monitoring. For example, when the interference within the management is dominant, the interference within the management can be reduced by performing the first transmission power control, so that the communication characteristics of the LoRa terminal within the management can be improved.

<Flow of the second example of channel allocation and transmission power control>
FIG. 7 is a flowchart of a second example of channel allocation and transmission power control. In FIG. 7, the same processing as in FIG. 5 is assigned the same reference numeral, and the description thereof will be omitted.

In the flowchart shown in FIG. 7, after measuring the interference (after S101), the base station 100 classifies the measured interference into unmanaged interference and in-managed interference (S201). Then, the processing after S102 is executed.

In the flowchart shown in FIG. 7, the base station 100 allocates the terminal z to the LoRa channel (S110) and selects the transmission power control for the terminal z assigned to the LoRa channel (transmission power control selection # 1) (S202). Then, the process of S102 is executed.

The process in S202 will be described with reference to FIG.

FIG. 8 is a flowchart executed in S202 of FIG.

The base station 100 determines whether or not unmanaged interference is dominant in the LoRa channel assigned to the terminal z (S203).

When unmanaged interference is dominant (YES in S203), the base station 100 does not perform the first transmission power control with respect to the terminal z (first transmission power control: OFF) (S204). Then, the flowchart shown in FIG. 8 ends, and the process of S102 in FIG. 7 is executed.

When the unmanaged interference is not dominant (NO in S203), the base station 100 performs the first transmission power control with respect to the terminal z (first transmission power control: ON) (S205). Here, the base station 100 does not perform the difference correction for each communication method in the first transmission power control of S205. Then, the flowchart shown in FIG. 8 ends, and the process of S102 in FIG. 7 is executed.

As described above, in the second example, the communication characteristics of the managed LoRa terminal can be improved by controlling the transmission power of the managed LoRa terminal assigned to the LoRa channel based on the result of the environmental monitoring. For example, when the interference within the management is dominant, the interference within the management can be reduced by performing the first transmission power control, so that the communication characteristics of the LoRa terminal within the management can be improved.

Note that FIG. 6 described above shows an example in which the usage conditions of channels # 24 to channel # 32, which are LoRa channels, are the same as each other, but the present disclosure is not limited to this. For example, the usage status of channels # 24 to channel # 32 may be different from each other. In this case, the selection result of the transmission power control method of A and B described above may be different for each channel of the LoRa channel. Further, the transmission power determined in the first transmission power control may be different for each channel. For example, when the GW reception power of the Wi-SUN terminal in management differs for each channel, the target of the equation (1) is determined for each channel.

Further, in the present embodiment, the case where two methods are used as the transmission power control method is shown, but the present disclosure is not limited to this, and three or more transmission power control methods are used. You may. For example, the base station 100 may adaptively select one or more from three or more transmission power control methods based on the result of environmental monitoring. For example, in the example of FIG. 8 described above, there are two different transmission power control methods (“first transmission power control: ON”) depending on whether the unmanaged interference is dominant or the unmanaged interference is not dominant. And "1st transmission power control: OFF"), but one or more is adaptively selected from three or more transmission power control methods according to the magnitude of the interference amount of unmanaged interference. You may. Further, for some of these different transmission power control methods, the same transmission power control method may be used to change the values of some parameters.

<Third example of channel allocation and transmission power control>
In the third example, in addition to the first transmission power control described above, transmission power control based on the diffusion rate of the LoRa method is performed. The transmission power control based on the diffusion rate of the LoRa method is described as the second transmission power control.

FIG. 9 is a diagram showing a third example of channel allocation and transmission power control. The horizontal axis and the vertical axis of FIG. 9 are the same as those of FIG. Further, since the allocation of the managed terminal to each channel is the same as the first example shown in FIG. 4, the description thereof will be omitted.

In FIG. 9, a second transmission power control is added to the second example shown in FIG.

For example, in the third example, the base station 100 performs the first transmission power control (first transmission power control: ON) and the second transmission power control for the managed LoRa terminal assigned to the shared channel. (Second transmission power control: ON). In the first transmission power control for the managed LoRa terminal assigned to the shared channel, the target value may be set to a relatively high value as in the first example.

Further, for example, in the third example, the base station 100 controls the transmission power of either A or B with respect to the managed LoRa terminal assigned to the LoRa channel. A is an option that does not perform the first transmission power control but performs the second transmission power control. B is an option of performing the first transmission power control and performing the second transmission power control. As in the second example, the base station 100 may select either A or B based on the result of environmental monitoring. For example, the base station 100 may select B if uncontrolled interference is dominant as a result of environmental monitoring on the LoRa channel, and select A if intra-managed interference is not dominant.

式（２）において、２^７／２^ｎは、ＬｏＲａ端末ｙが、ＳＦｎ（ｎは、例えば、７～１２のいずれか１つの整数）の拡散率を使用する場合のＬｏＲａ方式の拡散率に基づく係数である。 <Example of second transmission power control>
Hereinafter, the second transmission power control for a certain LoRa terminal y will be described. The second transmission power control is performed using, for example, the equation (2).

^In equation (2), 27/2 ⁿ is based on the diffusion coefficient of the LoRa method when the LoRa terminal y uses the diffusion coefficient of SFn (n is, for example, an integer of any one of 7 to 12). It is a coefficient.

Further, in the equation (2), Txpow _SFn indicates the transmission power of the LoRa terminal y after the second transmission power control, and _Txpow rev indicates the transmission power of the LoRa terminal y before the second transmission power control.

Here, when both the first transmission power control and the second transmission power control are performed, for example, in the case of transmission power control for the managed LoRa terminal assigned to the shared channel, the _Txpow rev uses the equation (1). It may be Txpower _next determined in the above. Further, when the first transmission power control is not performed and the second transmission power control is performed, for example, in the case of the transmission power control of the managed LoRa terminal assigned to the LoRa channel in which unmanaged interference is dominant, the _Txpow rev is It may be the transmission power Txpow _now of the LoRa terminal y within the management at the present time.

As shown in FIG. 9, by controlling the transmission power for the managed LoRa terminal, for example, deterioration of the communication characteristics of the managed Wi-SUN terminal can be suppressed, and the communication characteristics of the managed LoRa terminal can be improved. For example, in FIG. 9, since the transmission power is controlled based on the diffusion rate of the LoRa method, it is possible to further improve the communication characteristics of the LoRa terminal in management.

<Flow of the third example of channel allocation and transmission power control>
FIG. 10 is a flowchart of a third example of channel allocation and transmission power control. In FIG. 10, the same processing as in FIG. 5 is assigned the same number and the description thereof will be omitted.

In the flowchart of FIG. 10, after deciding whether or not to perform the first transmission power control (after S109 or S110), the base station 100 controls the diffusion rate (assignment of the diffusion rate) to the terminal z (S301). ).

Then, the base station 100 performs the second transmission power control with respect to the terminal z (second transmission power control: ON) (S302). In S302, the base station 100 weights the transmission power of the terminal z according to the diffusion rate of the terminal z. Then, the process of S102 is executed.

As described above, in the third example, by controlling the transmission power for the managed LoRa terminal, for example, deterioration of the communication characteristics of the managed Wi-SUN terminal can be suppressed, and the communication characteristics of the managed LoRa terminal can be suppressed. Can be improved. For example, in FIG. 9, since the transmission power is controlled based on the diffusion rate of the LoRa method, it is possible to further improve the communication characteristics of the LoRa terminal in management.

Note that FIG. 9 described above shows an example in which the usage conditions of channels # 24 to channel # 32, which are LoRa channels, are the same as each other, but the present disclosure is not limited to this. For example, the usage status of channels # 24 to channel # 32 may be different from each other. In this case, the selection result of the transmission power control method of A and B described above may be different for each channel of the LoRa channel. Further, although the usage status of the shared channels, channel # 33 to channel # 38, is the same as each other, the present disclosure is not limited to this. For example, the usage status of channels # 33 to channel # 38 may be different from each other. Further, the transmission power determined in the first transmission power control may be different for each channel. For example, when the GW reception power of the Wi-SUN terminal in management differs for each channel, the target of the equation (1) is determined for each channel.

<Fourth example of channel allocation and transmission power control>
In the first example to the third example, an example in which the managed LoRa terminal and the managed Wi-SUN terminal are assigned to the shared channel is shown, but in the fourth example, the managed Wi-SUN terminal is assigned to the shared channel. Will be described as an example in which is not assigned. The example in which the managed Wi-SUN terminal is not assigned to the shared channel is an example in which the number of managed Wi-SUN terminals to be allocated is the number that can be assigned to the Wi-SUN channel.

FIG. 11 is a diagram showing a fourth example of channel allocation and transmission power control. The horizontal axis and the vertical axis of FIG. 11 are the same as those of FIG. Further, since the allocation of the managed LoRa terminals to each channel is the same as the first example shown in FIG. 4, the description thereof will be omitted.

In the fourth example, as described above, the managed Wi-SUN terminal is not assigned to the shared channel. In this case, the base station 100 may perform transmission power control for the managed LoRa terminal assigned to the shared channel in the same manner as for transmission power control for the managed LoRa terminal assigned to the LoRa channel.

For example, in FIG. 11, the transmission power control for the managed LoRa terminal assigned to the LoRa channel is the same as the transmission power control for the managed LoRa terminal assigned to the LoRa channel shown in the third example. Then, in FIG. 11, the transmission power control for the managed LoRa terminal assigned to the shared channel is the same as the transmission power control for the managed LoRa terminal assigned to the LoRa channel.

Further, FIG. 11 shows an example of transmission power control for the managed LoRa terminal assigned to the shared channel when the managed Wi-SUN terminal is not assigned to the shared channel, but the present disclosure is not limited to this. Even when the number of Wi-SUN terminals assigned to the shared channel is less than the predetermined value, the transmission power control for the managed LoRa terminal assigned to the shared channel is the transmission power control for the managed LoRa terminal assigned to the LoRa channel. May be similar to.

<Flow of the fourth example of channel allocation and transmission power control>
FIG. 12 is a flowchart of a fourth example of channel allocation and transmission power control. In FIG. 12, the same processing as in FIGS. 5 and 7 is assigned the same number and the description thereof will be omitted.

In the flowchart shown in FIG. 12, the base station 100 is assigned to the terminal z and the shared channel (S108), and the transmission power control for the terminal z assigned to the shared channel is selected (transmission power control selection # 2) (S401). Then, the process of S102 is executed.

The process in S401 will be described with reference to FIG.

FIG. 13 is a flowchart executed in S401 of FIG.

The base station 100 determines whether or not a terminal using the Wi-SUN method exists (is assigned) in the shared channel assigned to the terminal z (S402).

When there is a terminal using the Wi-SUN method (YES in S402), the base station 100 performs the first transmission power control with respect to the terminal z (first transmission power control: ON) (S403). In the first transmission power control here, as illustrated in FIGS. 4 and 11, the target value (target of the equation (1)) may be set to a relatively high value. Then, the flowchart shown in FIG. 13 ends, and the process of S102 in FIG. 12 is executed.

If there is no terminal that uses the Wi-SUN method (NO in S402), the base station 100 is. It is determined whether or not unmanaged interference is dominant in the shared channel assigned to the terminal z (S404).

When unmanaged interference is dominant (YES in S404), the base station 100 does not perform the first transmission power control with respect to the terminal z (first transmission power control: OFF) (S405). Then, the flowchart shown in FIG. 13 ends, and the process of S102 in FIG. 12 is executed.

When the unmanaged interference is not dominant (NO in S404), the base station 100 performs the first transmission power control with respect to the terminal z (first transmission power control: ON) (S406). Here, the base station 100 does not perform the difference correction for each communication method in the first transmission power control of S406. Then, the flowchart shown in FIG. 13 ends, and the process of S102 in FIG. 12 is executed.

As described above, in the fourth example, the transmission power control for the managed LoRa terminal of the shared channel is performed according to the allocation status of the managed Wi-SUN terminal, for example, for example, the managed Wi-SUN terminal. Deterioration of communication characteristics can be suppressed, and communication characteristics of managed LoRa terminals can be improved.

Note that FIG. 11 described above shows an example in which the usage conditions of channels # 24 to channel # 32, which are LoRa channels, are the same as each other, but the present disclosure is not limited to this. For example, the usage status of channels # 24 to channel # 32 may be different from each other. In this case, the selection result of the transmission power control method of A and B described above may be different for each channel of the LoRa channel. Further, although the usage status of the shared channels, channel # 33 to channel # 38, is the same as each other, the present disclosure is not limited to this. For example, the usage status of channels # 33 to channel # 38 may be different from each other. In this case, the selection result of the transmission power control method of A and B described above may be different for each channel of the shared channel. Further, the transmission power determined in the first transmission power control may be different for each channel.

<Variation 1-1 of channel allocation>
In the first to fourth examples described above, the example in which the base station 100 allocates the managed terminal to the channel according to the magnitude of the GW received power has been described, but the present disclosure is not limited to this. The variations of channel allocation will be described below.

FIG. 14 is a diagram showing an example of variation 1-1 of channel allocation. The horizontal axis and the vertical axis of FIG. 14 are the same as those of FIG. Further, since the allocation of the managed Wi-SUN terminal to each channel is the same as the first example shown in FIG. 4, the description thereof will be omitted. Further, since the transmission power control for the managed LoRa terminal assigned to the LoRa channel and the shared channel is the same as that in the first example, the description thereof will be omitted.

In variation 1-1, the base station 100 determines the allocation of the managed terminals based on the GW received power and the communication success rate. The GW received power and the communication success rate are examples of information on communication quality. The communication success rate indicates, for example, whether or not communication is successful within a predetermined time Tk.

For example, the base station 100 allocates the managed LoRa terminal, which has a relatively large GW reception power and has succeeded in communication within a predetermined time Tk, to the shared channel. Further, the base station 100 allocates a managed LoRa terminal having a relatively small GW received power or a managed LoRa terminal whose communication is not successful within a predetermined time Tk to the LoRa channel. In other words, even when the GW reception power is relatively large, the managed LoRa terminal whose communication is not successful within the predetermined time Tk is assigned to the LoRa channel instead of the shared channel.

For example, the base station 100 allocates a managed LoRa terminal whose communication is not successful within a predetermined time Tk to the LoRa channel. Then, the base station 100 allocates the managed LoRa terminal having a relatively small GW reception power to the LoRa channel among the managed LoRa terminals whose communication is successful within the predetermined time Tk. Then, when the number of managed LoRa terminals assigned to the LoRa channel reaches the number of managed LoRa terminals that can be assigned to the LoRa channel, the base station 100 is in the remaining management in which communication is successful within a predetermined time Tk. Allocate a LoRa terminal to a shared channel.

<Flow of variation 1-1 of channel allocation>
FIG. 15 is a flowchart of variation 1-1 of channel allocation. In FIG. 15, the same processing as in FIG. 5 is assigned the same reference numeral and the description thereof will be omitted.

In the flowchart shown in FIG. 15, when the GW received power of the terminal z is larger than the second threshold value (YES in S107), the base station 100 determines whether or not the terminal z has succeeded in communication within a predetermined time Tk. (S501).

When the communication is successful within the predetermined time Tk (YES in S501), the base station 100 allocates the terminal z to the shared channel (S108). Then, the base station 100 performs the first transmission power control with respect to the terminal z (first transmission power control: ON) (S109). Then, the process of S102 is executed.

When the GW reception power of the terminal z is not larger than the second threshold value (NO in S107), or when the communication is not successful within the predetermined time Tk (NO in S501), the base station 100 sets the terminal z. Assigned to the LoRa channel (S110). Then, the base station 100 does not perform the first transmission power control with respect to the terminal z (first transmission power control: OFF) (S111). Then, the process of S102 is executed.

Among the managed LoRa terminals assigned to the shared channel, the managed LoRa terminal whose communication is not successful within the predetermined time Tk may be reassigned (reassigned) from the shared channel to the LoRa channel.

<Variation 1-2 of channel allocation>
FIG. 16 is a diagram showing an example of variation 1-2 of channel allocation. The horizontal axis and the vertical axis of FIG. 16 are the same as those of FIG. FIG. 16 shows that the allocation change from the LoRa channel to the shared channel is performed as compared to FIG.

In this case, among the managed LoRa terminals that have succeeded in communication within the predetermined time Tk, the managed LoRa terminal having a relatively large GW received power is assigned to the shared channel, and the managed LoRa terminal having a relatively small GW received power is assigned to the shared channel. The terminal does not have to be assigned to a shared channel. For example, it may be decided whether or not to perform reassignment depending on the usage status of the LoRa channel. Further, when reallocating, the managed LoRa terminal that changes the allocation to the shared channel may be determined according to the usage status of the LoRa channel. For example, if the usage status of the LoRa channel exceeds a predetermined level, reassignment from the LoRa channel to the shared channel may be executed.

In such an allocation, the GW reception power is relatively large, but the managed LoRa terminal that takes a long time to succeed in communication is allocated to the LoRa channel, so that the time required for the successful communication of the LoRa terminal in management can be shortened.

<Flow of variation 1-2 of channel allocation>
FIG. 17 is a flowchart of variation 1-2 of channel allocation. The flow shown in FIG. 17 is periodically performed, for example, for the managed _LoRa terminal ZL assigned to the LoRa channel #m.

The base station 100 determines whether or not the usage level of the LoRa channel #m is larger than the third threshold value (S503). For example, the usage level of LoRa channel # m may be the number of managed LoRa terminals assigned to LoRa channel # m. Alternatively, the usage level of the LoRa channel #m may be a value based on the number of managed LoRa terminals assigned to the LoRa channel #m and the transmission probability of each managed LoRa terminal.

When the usage level of the LoRa channel #m is higher than the third threshold value (YES in S503), the base station 100 determines whether or not the GW reception power of the managed LoRa terminal Z _L is larger than the fourth threshold value. (S504).

When the GW reception power of the managed LoRa terminal Z _L is larger than the fourth threshold value (YES in S504), the base station 100 determines whether or not the managed LoRa terminal Z _L has succeeded in communication within a predetermined time Tk. (S505).

If the communication is successful within the predetermined time Tk (YES in S505), the base station 100 reassigns the terminal Z _L to the shared channel (S506). Then, the flow of FIG. 17 ends.

When the usage level of LoRa channel #m is not larger than the third threshold value (NO in S503), when the GW reception power of the managed LoRa terminal Z _L is not larger than the fourth threshold value (NO in S504), or If the communication is not successful within the predetermined time Tk (NO in S505), the base station 100 does not change the allocation of the managed _LoRa terminal ZL to the LoRa channel #m, and the flow of FIG. 17 is as follows. finish.

In the variation described above, by performing allocation based on GW received power and transmission power control for the managed LoRa terminal allocated to the shared channel, for example, deterioration of the communication characteristics of the managed Wi-SUN terminal can be suppressed, and within the management. The communication characteristics of the LoRa terminal can be improved.

<Variation 2 of channel allocation>
In variation 2 of channel allocation, the channel allocation is changed according to the result of environmental monitoring.

FIG. 18 is a diagram showing an example of variation 2 of channel allocation. FIG. 18 shows channel allocation for two cases with different amounts of unmanaged interference. The vertical and horizontal axes of each of the two cases are the same as in FIG.

Of the two cases, the case 1 in which the interference amount of uncontrolled interference (for example, the usage status shown on the vertical axis in FIG. 18) is relatively low is an example of the case in which the interference within control is dominant. In case 1, since the interference amount of unmanaged interference is relatively low, the base station 100 may equally allocate the managed LoRa terminals to the LoRa channel and the shared channel. For example, in this case, the base station 100 keeps the difference between the number of managed LoRa terminals allocated to the LoRa channel and the number of managed LoRa terminals allocated to the shared channel within a predetermined range (for example, within a range of ± 2).

Further, in Case 1, the base station 100 may equally allocate the managed Wi-SUN terminals to the Wi-SUN channel and the shared channel. For example, in this case, the base station 100 keeps the difference between the number of managed Wi-SUN terminals assigned to the Wi-SUN channel and the number of managed Wi-SUN terminals assigned to the shared channel within a predetermined range (for example, ± 2). Within the range).

Of the two cases, the case 2 in which the interference amount of unmanaged interference is relatively high is an example of the case in which unmanaged interference is dominant. In Case 2, since the amount of unmanaged interference is relatively high, the base station 100 may allocate more managed LoRa terminals to the LoRa channel than to the shared channel. In other words, in Case 2, the base station 100 sets the difference obtained by subtracting the number of managed LoRa terminals allocated to the shared channel from the number allocated to the LoRa channel to a predetermined value or more.

Further, in Case 2, the base station 100 may allocate more managed Wi-SUN terminals to the Wi-SUN channel than to the shared channel. In other words, in Case 2, the base station 100 sets the difference obtained by subtracting the number of managed Wi-SUN terminals allocated to the shared channel from the number allocated to the Wi-SUN channel to a predetermined value or more.

<Flow of variation 2 of channel allocation>
FIG. 19 is a flowchart of variation 2 of channel allocation. In FIG. 19, the same processing as in FIGS. 5 and 7 is assigned the same number and the description thereof will be omitted.

In the flowchart shown in FIG. 19, the base station 100 sets the channel to be assigned to the terminal after classifying the interference (after S201) (S601). Then, the processing after S102 is executed.

The processing in S601 will be described with reference to FIG.

FIG. 20 is a flowchart executed in S601 of FIG.

Base station 100 determines whether the average unmanaged interference of each channel is dominant (S602).

When unmanaged interference is not dominant (NO in S602), base station 100 sets the allocation ratio between the non-shared channel and the shared channel to a (a is a number greater than 0) (S604). .. Here, the allocation ratio is represented by, for example, the number of managed terminals assigned to the shared channel / the number of managed terminals assigned to the non-shared channel. The higher the allocation ratio, the greater the number of managed terminals assigned to shared channels than the number of managed terminals assigned to non-shared channels.

When unmanaged interference is dominant (YES in S602), base station 100 sets the allocation ratio between the non-shared channel and the shared channel to b (b is a number greater than 0 and less than a). (S603). Here, when b is set to a value smaller than a and unmanaged interference is dominant, the ratio of allocation to the non-shared channel is higher than that of the shared channel.

Then, the base station 100 determines a first threshold value (see S104 in FIG. 19) and a second threshold value (see S107 in FIG. 19) based on the set ratio (S605). Then, the flow of FIG. 20 ends, and S102 of FIG. 19 is executed. For example, the larger the first threshold and the second threshold, the more the number of managed terminals assigned to the non-shared channel. Therefore, when the allocation ratio is b (for example, when unmanaged interference is dominant), the first threshold is used. And the second threshold value may be set to a value larger than the first threshold value and the second threshold value when the allocation ratio is a (for example, when intra-management interference is dominant), respectively.

In such an allocation, the ratio between the number of managed LoRa terminals allocated to the LoRa channel and the number of managed LoRa terminals allocated to the shared channel is changed according to the magnitude of the interference amount of unmanaged interference, so that the radio wave environment The communication characteristics of the managed LoRa terminal can be improved regardless of the state of (for example, the magnitude of the interference amount of unmanaged interference).

Further, in such an allocation, the number of managed Wi-SUN terminals allocated to the Wi-SUN channel and the number of managed Wi-SUN terminals allocated to the shared channel are set according to the magnitude of the interference amount of unmanaged interference. Since the ratio is changed, the communication characteristics of the managed Wi-SUN terminal can be improved regardless of the state of the radio wave environment (for example, the magnitude of the interference amount of unmanaged interference).

<Variation 3 of channel allocation>
In the variation 3 of the channel allocation, an example of the channel allocation independent for each communication method will be described.

FIG. 21 is a diagram showing an example of variation 3 of channel allocation. The horizontal axis and the vertical axis of FIG. 21 are the same as those of FIG.

In FIG. 21, the ratio RL of the managed LoRa terminal assigned to the LoRa channel and the managed _LoRa terminal assigned to the shared channel, and the managed Wi-SUN terminal assigned to the Wi-SUN channel and the managed Wi-SUN assigned to the shared channel. The second ratio _RW with the terminal is set independently.

For example, the ratio _RL is set to be larger than the ratio _RW . In other words, the managed LoRa terminal may be set to a higher ratio to the shared channel than the managed Wi-SUN terminal.

<Flow of variation 3 of channel allocation>
The flowchart of variation 3 of channel allocation is the same as the flowchart of variation 2 of channel allocation shown in FIG. 19, but the processing of S601 is different from that of FIG. Hereinafter, the process of S601 in the flowchart of the variation 3 of the channel allocation will be described with reference to FIG. 22.

FIG. 22 is a flowchart executed in S601 of FIG.

The base station 100 determines whether or not the average unmanaged interference of each channel is dominant (S701).

When unmanaged interference is not dominant (NO in S701), base station 100 sets the allocation ratio between the shared channel and the LoRa channel to a (a is a number greater than 0) (S702). Further, the base station 100 sets the allocation ratio between the shared channel and the Wi-SUN channel to c (c is a number larger than 0) (S703).

When unmanaged interference is dominant (YES in S701), base station 100 sets the allocation ratio between the shared channel and the LoRa channel to b (b is a number greater than 0 and less than a) (S704). ). Further, the base station 100 sets the allocation ratio between the shared channel and the Wi-SUN channel to d (d is a number larger than 0 and smaller than c) (S705).

Here, when b is set to a value smaller than a and unmanaged interference is dominant, the ratio of managed LoRa terminals assigned to the LoRa channel is higher than that of the shared channel. Further, when d is set to a value smaller than c and unmanaged interference is dominant, the ratio of managed Wi-SUN terminals assigned to the Wi-SUN channel is higher than that of the shared channel. Further, when a is set to a value larger than c and b is set to a value larger than d, the ratio of the managed LoRa terminal assigned to the shared channel is the ratio of the managed Wi-SUN terminal. Is higher than the percentage assigned to the shared channel.

Then, the base station 100 determines the first threshold value (see S104 in FIG. 19) and the second threshold value (see S107 in FIG. 19) based on the set ratio (S706). Then, the flow of FIG. 20 ends, and S102 of FIG. 19 is executed. For example, the first threshold value when the allocation ratio is b is set to be larger than the first threshold value when the allocation ratio is a. Further, the second threshold value when the allocation ratio is d is set to be larger than the second threshold value when the allocation ratio is c, respectively.

Further, in such an allocation, the number of managed Wi-SUN terminals allocated to the Wi-SUN channel and the number of managed Wi-SUN terminals allocated to the shared channel are set according to the magnitude of the interference amount of unmanaged interference. Since the ratio is changed, the communication characteristics of the managed Wi-SUN terminal can be improved regardless of the state of the radio wave environment (for example, the magnitude of the interference amount of unmanaged interference).

In the above-described embodiment, the interference classification classified into the interference within the control and the interference outside the control has been described, but the present disclosure is not limited to this. For example, unmanaged interference may be classified into radio interference and environmental noise. In this case, the control method of transmission power control may be selected based on the usage status of radio wave interference in each channel (channel occupancy rate information). Further, with respect to environmental noise, a high priority may be specified. For example, the control method of the transmission power control may be selected based on the radio wave interference and the usage status (channel occupancy rate information) of the environmental noise having a high priority.

For example, radio wave interference and environmental noise may be classified based on preamble information. Further, with respect to the environmental noise, the information of the wireless system (for example, the high priority) that causes the environmental noise may be estimated from the band information.

Further, in the above embodiment, the LoRa channel is a channel to which a LoRa terminal is assigned and a Wi-SUN terminal is not assigned, but the present disclosure is not limited to this. For example, a channel in which the number (or usage status) to which Wi-SUN terminals are allocated is less than the threshold value may be regarded as an example of "LoRa channel". For example, in the above-mentioned fourth example, the example in which the managed Wi-SUN terminal is not assigned to the shared channel is shown, but the managed Wi-SUN terminal less than the threshold value may be assigned to the shared channel.

Further, in the above embodiment, an example is shown in which channel allocation to a terminal and transmission power control to the terminal are sequentially executed for each terminal, but the present disclosure is not limited to this. For example, the base station 100 may control the transmission power of each terminal after allocating each of the terminals to be allocated to the channel. In this case as well, the base station 100 may perform transmission power control according to the allocation status of the terminals of each channel.

Further, each example of channel allocation and transmission power control and each variation of channel allocation shown in the above embodiment may be applied in combination. For example, the transmission power control shown in the first example may be applied to the shared channel, and the transmission power control shown in the third example may be applied to the LoRa channel. Further, for example, the transmission power control of each channel in the variation 1-1 of the channel allocation shown in FIG. 14 may be changed to the transmission power control shown in the second example or the third example. Further, the transmission power control may be independently set for each of the plurality of LoRa channels and / or the plurality of shared channels. For example, in one LoRa channel, the transmission power control shown in the first example may be applied, and in another LoRa channel, the transmission power control shown in the third example may be applied.

<Variation 4 of channel allocation>
The above-mentioned channel allocation shows an example of determining the channel to be assigned to the managed terminal from the LoRa channel, the Wi-SUN channel, and the shared channel. There may be a plurality of LoRa channels, Wi-SUN channels, and shared channels, respectively. For example, in the example of FIG. 4, channels # 24 to channel # 32 are LoRa channels, channels # 33 to channel # 38 are shared channels, and channels # 39 to channel # 60 are Wi-SUN channels. Is.

Hereinafter, one or more LoRa channels are described as "LoRa channel group (CG)", one or more Wi-SUN channels are described as "Wi-SUNCG", and one or more shared channels are described as "shared CG". May be described as. That is, in the above example, "assigning to a LoRa channel" may correspond to "assigning to a channel in LoRaCG". Further, "assigning to a Wi-SUN channel" corresponds to "assigning to a channel in Wi-SUNCG", and "assigning to a shared channel" means "assigning to a channel in shared CG". It may be equivalent.

For example, the base station 100 determines the managed terminals to be assigned to the shared channel, and then assigns the channels to be assigned to each of the determined managed terminals to a plurality of channels (for example, channels # 33 to # 38) included in the shared CG. It may be randomly determined from among them. The same may apply to LoRaCG and Wi-SUNCG.

Alternatively, the base station 100 determines the managed terminal to which the shared channel is assigned, and then assigns the channel to be assigned to each of the determined managed terminals from among a plurality of channels included in the shared CG by using the method shown below. You may decide. The same may apply to LoRaCG and Wi-SUNCG.

In the following, an example of determining a channel to be assigned to each of the managed terminals from a plurality of channels included in the shared CG will be described.

<Variation 4-1>
FIG. 23 is a diagram showing an example of variation 4-1 of channel allocation. The horizontal axis of FIG. 23 shows the frequency, and the vertical axis shows the usage level of each channel. FIG. 23 shows the usage levels of the managed terminal and the unmanaged terminal in each of the four channels (channels # C ₁ to # C ₄ ) with identification numbers. Further, FIG. 23 shows n managed terminals assigned to any of channels # C ₁ , # C ₂ , # C ₃ , and # C ₄ .

For example, channels # C ₁ to # C ₄ indicate four channels included in the shared CG. Further, for example, when channels # C ₁ to # C ₄ are shared CG channels, the n managed terminals are managed LoRa terminals or managed Wi-SUN terminals determined to be assigned to the shared CG.

Channels # C ₁ to # C ₄ may be classified according to the usage status of unmanaged terminals. For example, channels # C ₁ and # C ₂ have lower levels of usage compared to channel # C ₃ . Therefore, channels # C ₁ and # C ₂ are classified as "channels with small unmanaged interference", and channels # C ₃ are classified as "channels with large unmanaged interference". Further, since channel # C ₄ is close to the upper limit value α of the usage status level, it may correspond to “a channel to which an in-managed terminal is not assigned”.

The "channel with low unmanaged interference" may be referred to as a "channel with a low occupancy rate of unmanaged interference" or a "channel with a large amount of vacancy". Further, the "channel with a large amount of unmanaged interference" may correspond to a "channel having a high occupancy rate of unmanaged interference" or a "channel with a small amount of vacancy". Further, the "channel to which the managed terminal is not assigned" may correspond to the "channel without vacancy". For example, "channel with small unmanaged interference" and "channel with large unmanaged interference" may be classified by comparing the threshold value with the amount of interference of unmanaged interference, or from the one with the largest unmanaged interference. A predetermined number of channels may be classified as "channels with high unmanaged interference" and the rest may be classified as "channels with low unmanaged interference". This classification may be performed by base station 100.

The base station 100 allocates an in-managed terminal assigned to a channel having less unmanaged interference and an in-managed terminal assigned to a channel having large in-managed interference, and the base station 100 receives a signal received from each of the managed terminals (for example,). , RSSI). Hereinafter, the RSSI determined by the base station 100 by receiving the signal transmitted by a certain managed terminal x may be described as "RSSI of the terminal x". Further, the terminal x of the transmission source of the signal indicating a certain RSSI may be described as "terminal x corresponding to RSSI".

In the example of FIG. 23, n managed terminals are arranged in the order of RSSI. Among the RSSIs of the n managed terminals, the RSSI of the managed terminal # 1 is the smallest, and the RSSI of the managed terminal # n is the largest. Then, in the example of FIG. 23, the n managed terminals are a group of m terminals consisting of managed terminals # 1 to # m corresponding to a relatively small RSSI, and a managed terminal corresponding to a relatively large RSSI. It is divided into a group of nm terminals consisting of terminals # m + 1 to # n. In addition, m is an integer of 1 or more and n or less. For example, m may be determined based on the ratio of the availability of channels # C ₁ and # C ₂ to the availability of channel # C ₃ .

The base station 100 decides to allocate the managed terminals # 1 to # m corresponding to the relatively small RSSI to the channels # C ₁ and # C ₂ having the small unmanaged interference, and manages the terminals corresponding to the relatively large RSSI. It is determined that the inner terminals # m + 1 to # n _are assigned to the channel # C3 having a large unmanaged interference.

Note that FIG. 23 shows an example of determining a channel to be assigned to each of the managed terminals from a plurality of channels included in the shared CG, but the same applies to Wi-SUNCG and LoRaCG. May be done. For example, if channels # C ₁ , # C ₂ , # C ₃ , and # C ₄ are Wi-SUNCG channels, n managed terminals are determined to be assigned to Wi-SUNCG. It is a SUN terminal. Further, for example, when channels # C ₁ to # C ₄ are LoRaCG channels, the n managed terminals are managed LoRa terminals determined to be assigned to LoRaCG.

FIG. 24 is a flowchart of variation 4 of channel allocation. In FIG. 24, the same processing as in FIG. 5 is assigned the same reference numeral, and the description thereof will be omitted. In the flow of FIG. 24, the processes of S102, S105, S106, S108, and S110 in the flow of FIG. 5 are replaced with the processes of S801, S802, S803, S804, and S805, respectively. Further, in the flow of FIG. 24, the process of S806 is added to the flow of FIG.

The base station 100 determines whether or not the allocation of the channel group to the subordinate terminals is completed (S801).

When the allocation is not completed (NO in S801), that is, when there is a terminal whose allocation process has not been completed (hereinafter referred to as "terminal z") among the terminals to be allocated, the base station 100 Executes the allocation process after S103 for the terminal z.

When the GW received power of the terminal z is larger than the first threshold value (YES in S104), the base station 100 determines that the terminal z is assigned to the shared CG (S802). Then, the process of S801 is executed.

When the GW received power of the terminal z is not larger than the first threshold value (NO in S104), the base station 100 determines that the terminal z is assigned to the Wi-SUNCG (S803). Then, the process of S801 is executed.

When the GW received power of the terminal z is larger than the second threshold value (YES in S107), the base station 100 determines that the terminal z is assigned to the shared CG (S804).

When the GW received power of the terminal z is not larger than the second threshold value (NO in S107), the base station 100 determines that the terminal z is assigned to the LoRaCG (S805).

On the other hand, when the allocation process of the channel group is completed (YES in S801), that is, when there is no terminal whose allocation process has not been completed among the terminals to be allocated, the inside of the channel group is based on RSSI. To determine the allocation channel for each allocation target (S806).

The process of S806 may be executed independently in each of the channel groups. In other words, each of the terminals decided to be assigned to LoRaCG becomes the allocation target, and the process of determining the channel to allocate each of the allocation targets and each of the terminals decided to be assigned to Wi-SUNCG become the allocation target and the allocation target. The process of determining the channel to be assigned to each and the process of determining the shared channel to which each of the terminals determined to be assigned to the shared CG becomes the allocation target and each of the allocation targets may be executed independently.

Then, the flow of FIG. 24 ends.

FIG. 25 is a flowchart corresponding to variation 4-1 executed in S806 of FIG. 24. The flow shown in FIG. 25 is executed independently for each of the managed terminal assigned to LoRaCG, the managed terminal assigned to the shared CG, and the managed terminal assigned to Wi-SUNCG.

In the following, an example is shown in which the managed terminal assigned to a certain group is the terminal to be assigned.

The base station 100 rearranges the managed terminals in ascending order of RSSI of each managed terminal (S901).

The base station 100 determines whether or not the allocation of the channel to the terminal to be allocated is completed (S902).

When the allocation is not completed (NO in S902), that is, when there is a terminal whose allocation process has not been completed (hereinafter referred to as "terminal z") among the terminals to be allocated, the base station 100 Executes the allocation process after S903 for the terminal z. On the other hand, when the allocation process is completed (YES in S902), that is, when there is no terminal whose allocation process has not been completed among the terminals to be allocated, the flow shown in FIG. 25 ends.

The base station 100 determines whether or not the terminal z can be assigned to a channel having less unmanaged interference (S903). For example, the base station 100 may determine that the terminal z can be assigned to a channel with less unmanaged interference if the RSSI of the terminal z corresponds to an RSSI that can be assigned to a channel with less unmanaged interference.

When the terminal z can be assigned to the channel with less unmanaged interference (YES in S903), the base station 100 allocates the terminal z to the channel with less unmanaged interference (S904). Then, the process of S902 is executed.

When the terminal z cannot be assigned to the channel with small unmanaged interference (NO in S903), the base station allocates the terminal z to the channel with large unmanaged interference (S905). Then, the process of S902 is executed.

As described above, in Variation 4-1 the managed terminal is assigned to another terminal (in other words, a channel with a lot of free space) in order from the managed terminal with the smallest RSSI to the channel with the smaller unmanaged interference (in other words, the channel with a lot of vacancy). For example, it is possible to reduce the interference given to the unmanaged terminal). For example, in the managed terminal, even if the control range of the transmission power (for example, the dynamic range) is not sufficient, the interference caused by the managed terminal can be reduced. Further, since the managed terminals having a relatively small difference in RSSI are assigned to the same channel, the influence of interference and interference can be reduced.

<Variation 4-2>
In the example of variation 4-1 (for example, FIG. 23), the base station 100 determines the channel to be assigned to the managed terminal based on RSSI, but in the variation 4-2, the base station 100 determines the channel to be assigned. The channel to be assigned to the managed terminal is determined based on the RSSI and the condition determination as to whether or not a certain condition is satisfied. Illustratively, in the following description, a certain condition is a condition regarding a time interval (hereinafter, communication success interval) from the latest timing of successful communication (the timing of the last successful communication) to the present time in the managed terminal. Is.

In the following, an example of determining a channel to be assigned to each of the managed terminals from a plurality of channels included in the shared CG will be described.

FIG. 26 is a diagram showing an example of variation 4-2 of channel allocation. The horizontal axis and the vertical axis of FIG. 26 are the same as those of FIG. 23. Further, the level of the usage status of the unmanaged terminals in each of the four channels (channels # C ₁ to # C ₄ ) is the same as in FIG. 23. Further, FIG. 26 shows n + v managed terminals assigned to any of channels # C ₁ , # C ₂ , # C ₃ , and # C ₄ .

Further, in FIG. 26, as in FIG. 23, channels # C ₁ and # C ₂ are classified as “channels with small unmanaged interference”, and channel # C ₃ is classified as “channels with large unmanaged interference”. Will be done. Further, since channel # C ₄ is close to the upper limit value α of the usage status level, it may correspond to “a channel to which an in-managed terminal is not assigned”.

Among the managed terminals, the base station 100 allocates a channel with less unmanaged interference to the managed terminals (“managed terminals satisfying the conditions” in FIG. 26) whose communication success interval is larger than a predetermined value. In FIG. 26, managed terminals # 1 to # v satisfying the conditions are assigned to channels with less unmanaged interference.

Then, the base station 100 rearranges n managed terminals (in other words, "managed terminals that do not satisfy the conditions") whose communication success interval is not larger than a predetermined value in the order of RSSI. Then, as in FIG. 23, the base station 100 decides to allocate channels # C ₁ and # C ₂ with small unmanaged interference to the managed terminals # 1 to # m corresponding to the relatively small RSSI. It is determined that the managed terminals # m + 1 to # n corresponding to the relatively large RSSI are assigned to the channel # C ₃ having a large unmanaged interference. Here, m is based on, for example, the ratio of the availability of channels # C ₁ and # C ₂ after assigning managed terminals satisfying v conditions to the availability of channel # C ₃ . May be decided.

Note that FIG. 26 shows an example of determining a channel to be assigned to each of the managed terminals from a plurality of channels included in the shared CG, as in FIG. 23, but for Wi-SUNCG and LoRaCG. However, it may be applied in the same manner. For example, if channels # C ₁ , # C ₂ , # C ₃ , and # C ₄ are Wi-SUNCG channels, n + v managed terminals are determined to be assigned to Wi-SUNCG. It is a SUN terminal. Further, for example, when channels # C ₁ to # C ₄ are LoRaCG channels, n + v managed terminals are managed LoRa terminals determined to be assigned to LoRaCG.

Next, the processing flow of variation 4-2 will be described. The processing flow of variation 4-2 is the same as that of variation 4-1 shown in FIG. 24, but the processing of S806 in FIG. 24 is different from that of variation 4-1.

FIG. 27 is a flowchart corresponding to variation 4-2 executed in S806 of FIG. 24. In FIG. 27, the same processing as in FIG. 25 is assigned the same reference numeral and the description thereof will be omitted. In the flow of FIG. 27, the process of S901 in FIG. 25 is replaced with the process of S1001 to S1004.

The base station 100 determines whether or not the confirmation regarding the communication success interval of the terminal to be assigned has been completed (S1001).

When the confirmation is not completed (NO in S1001), that is, when there is a terminal (hereinafter referred to as "terminal y") for which the confirmation regarding the communication success interval has not been completed among the terminals to be allocated. The base station 100 executes the confirmation process of S1002 for the terminal y.

The base station 100 determines whether or not the communication success interval of the terminal y is larger than a predetermined value (S1002).

When the communication success interval of the terminal y is not larger than the predetermined value (NO in S1002), the process of S1001 is executed.

When the communication success interval of the terminal y is larger than a predetermined value (YES in S1002), the base station 100 allocates the terminal y to the channel with less unmanaged interference (S1003). Then, the process of S1001 is executed.

When the confirmation is completed (YES in S1001), that is, when there is no terminal to which the confirmation regarding the communication success interval has not been completed among the terminals to be allocated, the base station 100 completes the channel allocation in S1003. The terminals excluding the assigned terminals are set as the allocation target terminals, and the terminals are rearranged in ascending order of RSSI of each allocation target (S1004). Then, the processing after S902 is executed.

Here, the number of managed terminals (in the above example, the managed terminals whose communication success interval is larger than a predetermined value) to which channels with a large number of vacant spaces are preferentially allocated may be variable depending on the channel resource. For example, if the channel resources are relatively small, the number of managed terminals that preferentially allocate channels with a lot of free space is increased, and if the channel resources are relatively large, the managed terminals that preferentially allocate channels with a lot of free space are used. You may reduce the number of. For example, the number of managed terminals to which preferentially allocate channels with a lot of free space may be determined based on the comparison result between the channel resource and the threshold value of 1 or more.

As described above, in variation 4-2, in addition to RSSI, the channel to be assigned to the managed terminal is determined based on the condition regarding the communication success interval. By this decision, the channel with a lot of free space can be assigned preferentially to the managed terminal having a long communication success interval, so that the increase in the communication success interval can be suppressed even when the channel resource is insufficient. For example, if the channel resource is not sufficient, there will be a terminal in which the channel is not allocated and the transmission opportunity cannot be obtained even though the RSSI is large. In the variation 4-2, the transmission opportunity can be given to such a terminal with priority. Further, since the managed terminals having a relatively small difference in RSSI are assigned to the same channel, the influence of interference and interference can be reduced.

<Variation 4-3>
In the example of variation 4-1 (for example, FIG. 23), the base station determines the channel to be assigned to the managed terminal based on RSSI, but in variation 4-3, the base station is changed to RSSI. , Determine the channel to be assigned to the managed terminal based on the type of managed terminal. Variation 4-3 is applied to the shared channel to which both the LoRa terminal and the Wi-SUN terminal are assigned.

FIG. 28 is a diagram showing an example of variation 4-3 of channel allocation. The horizontal axis and the vertical axis of FIG. 28 are the same as those of FIG. 23. Further, the level of the usage status of the unmanaged terminals in each of the four channels (channels # C ₁ to # C ₄ ) is the same as in FIG. 23. However, since variation 4-3 is applied to the shared channel, each of the four channels is a shared channel.

Further, FIG. 28 shows n + p managed terminals assigned to any of channels # C ₁ , # C ₂ , # C ₃ , and # C ₄ . Here, the n + p managed terminals are a managed Wi-SUN terminal or a managed LoRa terminal, respectively.

Further, in FIG. 28, similarly to FIG. 23, channels # C ₁ and # C ₂ are classified as “channels with small unmanaged interference”, and channels # C ₃ are classified as “channels with large unmanaged interference”. Will be done. Further, since channel # C ₄ is close to the upper limit value α of the usage status level, it may correspond to “a channel to which an in-managed terminal is not assigned”.

Among the managed terminals, the base station 100 allocates the managed Wi-SUN terminal (abbreviated as “managed Wi-SUN” in FIG. 28) to the channel with less unmanaged interference. In FIG. 28, the managed Wi-SUN terminals # 1 to #p are assigned to channels with less unmanaged interference.

Then, the base station 100 rearranges the managed LoRa terminals (abbreviated as “managed LoRa” in FIG. 28) in the order of RSSI. Similar to FIG. 23, the base station 100 decides to allocate the managed LoRa terminals # 1 to # m corresponding to the relatively small RSSI to the channels # C ₁ and # C ₂ having less unmanaged interference, and compares them. It is determined that channel # C3 with small unmanaged interference is assigned to the managed _LoRa terminals # m + 1 to # n corresponding to the large RSSI. Here, m is based on, for example, the ratio of the availability of channels # C ₁ and # C ₂ after allocating p managed Wi-SUN terminals to the availability of channel # C ₃ . May be decided.

Next, the processing flow of variation 4-3 will be described. The processing flow of variation 4-3 is the same as that of variation 4-1 shown in FIG. 24, but the processing of S806 in FIG. 24 is different from that of variation 4-1.

FIG. 29 is a flowchart corresponding to variation 4-3 executed in S806 of FIG. 24. In FIG. 29, the same processing as in FIG. 25 is assigned the same reference numeral and the description thereof will be omitted. In the flow of FIG. 29, the process of S901 in FIG. 25 is replaced with the process of S1101 to S1104.

The base station 100 determines whether or not the confirmation of the communication method of the terminal to be assigned is completed (S1101).

When the confirmation of the communication method is not completed (NO in S1101), that is, there is a terminal (hereinafter referred to as "terminal y") for which the confirmation of the communication method has not been completed among the terminals to be assigned. In this case, the base station 100 executes the confirmation process of S1102 for the terminal y.

The base station 100 determines whether or not the communication method of the terminal y is the Wi-SUN method (S1102).

When the communication method of the terminal y is not the Wi-SUN method (NO in S1102), the process of S1101 is executed.

When the communication method of the terminal y is the Wi-SUN method (YES in S1102), the base station 100 allocates the terminal y to the channel with less unmanaged interference (S1103). Then, the process of S1101 is executed.

When the confirmation of the communication method is completed (YES in S1101), that is, when there is no terminal whose communication method has not been confirmed among the terminals to be allocated, the base station 100 allocates the channel in S1103. The terminals excluding the terminals (Wi-SUN terminals in management) for which the above is completed are set as the terminals to be allocated, and the terminals are rearranged in ascending order of RSSI of each of the allocation targets (S1104). Then, the processing after S902 is executed.

Here, depending on the number of managed Wi-SUN terminals and channel resources, the number of managed Wi-SUN terminals that are preferentially allocated to channels with less unmanaged interference may be limited. For example, when the number of managed Wi-SUN terminals is relatively small with respect to the channel resource, the number of managed Wi-SUN terminals may be increased preferentially to the channel with less unmanaged interference. In other words, in this case, it is not necessary to limit the number of managed Wi-SUN terminals preferentially assigned to channels with less unmanaged interference. Further, when the number of managed Wi-SUN terminals is relatively large with respect to the channel resource, the number of managed Wi-SUN terminals to be preferentially allocated to channels with less unmanaged interference may be reduced. In other words, in this case, the number of managed Wi-SUN terminals preferentially assigned to channels with less unmanaged interference may be limited. The number to be limited (the number to be reduced) may be determined by the channel resource.

As described above, in variation 4-3, in addition to RSSI, the channel to be assigned to the managed terminal is determined based on the communication method. By this determination, the communication quality of the Wi-SUN method, which has a weaker error tolerance than the LoRa method, can be improved. Further, since the managed terminals having a relatively small difference in RSSI are assigned to the same channel, the influence of interference and interference can be reduced.

In the variations 4-1 to 4-3 described above, examples are classified into "channels with large unmanaged interference" and "channels with small unmanaged interference" according to the difference in the relative magnitude of unmanaged interference. As shown, the present disclosure is not limited to this. For example, variations 4-1 to 4-3 may be applied when the relative difference in uncontrolled interference is small and the uncontrolled interference is substantially uniform. For example, a terminal corresponding to a relatively small RSSI may be assigned to a specific channel, and a terminal corresponding to a relatively large RSSI may be assigned to a channel other than the specific channel. By this method, since the terminals in the management having a relatively small difference in RSSI are assigned to the same channel, the influence of interference and interference can be reduced.

Further, the above-mentioned variations 4-1 to 4-3 may be used as a dedicated channel when there is a vacancy in the dedicated channel such as the LoRa channel and the Wi-SUN channel. Alternatively, the above-mentioned variations 4-1 to 4-3 may be used as a shared channel when there is no vacancy in the dedicated channel and there is a vacancy in the shared channel.

Further, the above-mentioned variations 4-1 to 4-3 may be used in combination, or may be applied independently for each group of each channel. For example, variation 4-1 may be applied to LoRaCG, variation 4-2 may be applied to Wi-SUNCG, and variation 4-3 may be applied to shared CG. Further, for example, variations 4-2 and 4-3 may be applied in combination to the shared CG.

Further, for example, one channel group may be divided into a plurality of subgroups, and the above-mentioned variations 4-1 to 4-3 may be independently applied to each subgroup.

In the above-mentioned examples of variations 4-1 to 4-3, the channels are "channels with small unmanaged interference" and "channels with large unmanaged interference" depending on the level of usage of unmanaged terminals. And "Channels to which managed terminals are not assigned" are shown, but the present disclosure is not limited to this. Depending on the magnitude of the usage level of the unmanaged terminal, the channels may be classified into four or more or two. In addition, there does not have to be a "channel to which the managed terminal is not assigned".

Further, in the example of variations 4-1 to 4-3, the in-managed terminal has two types of channels, "a channel with small unmanaged interference" and "a channel with large unmanaged interference", depending on the size of RSSI. Although an example of being classified into two groups assigned to is shown, the present disclosure is not limited to this. For example, if channels are classified into four or more types according to the level of usage of unmanaged terminals, the managed terminals correspond to the number of channel classifications according to the size of RSSI. It may be divided into three or more groups. Further, for example, the managed terminals may be classified into a number excluding "channels to which the managed terminals are not assigned".

Further, in the above-mentioned variations 4-1 to 4-3, an example in which the base station determines the channel allocation based on RSSI is shown, but the present disclosure is not limited to this. For example, instead of RSSI or in combination with RSSI, information about other communication qualities such as signal-to-interference power ratio may be used. The RSSI described above and the "GW received power" may have the same information or may be different from each other.

In the above description, the processing flow of variations 4-1 to 4-3 has been described as the flowchart illustrated in FIG. 25, but the present disclosure is not limited to this. For example, in the flowchart illustrated in FIG. 25, the ON / OFF process of the first transmission power control (S109 and S111 in FIG. 25) may be skipped. In other words, variation 4 may be applied in the absence of transmit power control.

In the above description, an example in which the processing flow of variations 4-1 to 4-3 is combined with the first example of the transmission power control exemplified in FIG. 5 has been described, but the present disclosure is not limited to this. For example, it may be combined with other transmission power control examples.

<Variation 5 of channel allocation>
Among the managed terminals, there may be managed terminals having different required communication qualities. This difference in communication quality requirements may be represented by the priority of channel allocation. That is, there may be managed terminals having different priority of channel allocation. For example, an intra-managed terminal with a relatively high priority may be assigned to a channel capable of higher quality communication than an intra-managed terminal with a relatively low priority. The channel capable of high-quality communication is, for example, a channel in which a plurality of communication methods are not mixed, and a channel in which unmanaged interference and / or in-managed interference is relatively small.

For example, a terminal with a relatively high priority is a terminal owned by a specific user. Specific users are, for example, elderly people with chronic diseases, people with guide dogs (guide dog users), elderly people who have special requests from people around them such as family members, or children with a lot of risky behavior history. be. The specific user may be a person who is desired to be watched intensively.

In addition, the specific user may be a person who has difficulty returning home to evacuate to a shelter in the event of a disaster. For example, when a specific user is a person who has difficulty returning home, a local resident (a person who can return home) corresponds to a user with a relatively low priority. Further, when there are many people who have difficulty returning home, for example, among those who have difficulty returning home, a person who is farther away from home may be set with a higher priority. Further, the priority may be set according to the attribute of the person. For example, a user whose home is relatively far from an evacuation center but has physical strength (in some cases, it is possible to return home on foot) is set to have a lower priority than a user who has difficulty returning home on foot. May be good. Whether or not the user has physical strength (for example, whether or not it is possible to return home on foot) may be determined based on the user's information such as the user's age, gender, presence or absence of injury, and presence or absence of illness. Alternatively, the presence or absence of the user's physical strength may be determined by the user's self-report.

Further, the specific user may be a person who waits at a specific place for a predetermined time or longer. For example, a person who has been waiting for a long time in a commercial facility, a theme park, a restaurant, or a stadium may have a higher priority.

Further, the specific user may be a person or the like in a specific place. For example, the specific user may be a person in the mountains or at sea. Further, the terminal owned by a specific user is not limited to the terminal owned by a person, and may be, for example, a terminal mounted on a machine, a robot, a drone, a ship, or the like existing in the mountains or at sea. A large number of terminals may exist around the coast, at the foot of a mountain, etc., and communication traffic may be congested. In order to give priority to communication in such a case, the priority of the terminal existing in the dangerous area in the mountains or the sea is set high. Further, when there are many people in the mountains or at sea, for example, a person who exists in a more dangerous area may be set with a higher priority. For example, in the mountains, the priority of a person in an area other than a general mountain trail, such as a rocky place, may be set higher than the priority of a person in a general mountain trail.

The specific user is not limited to these examples. Based on the user information associated with the terminal, it may be determined whether the terminal has a relatively high priority. For example, the base station 100 may refer to the information of the user registered in the terminal via the terminal. Further, the base station 100 may acquire the position information of the terminal or the like and determine whether or not the terminal is a terminal of a specific user.

Further, for example, a terminal having a relatively high priority is a terminal that provides a specific service to the owner of the terminal. The specific service may be, for example, a watching service for a user who owns a terminal. Alternatively, the specific service may be an information notification service regarding life-threatening diseases and / or infectious diseases. Alternatively, the specific service may be a service related to a life-threatening situation such as traffic accident prevention and / or disaster countermeasures. The terminal that provides a specific service may be a terminal dedicated to the service, or may be a terminal that has started an application that provides the service among the applications executed by the terminal.

Hereinafter, a terminal having a relatively high priority may be described as a terminal of a specific user / service. The terminal of a specific user / service may be a terminal satisfying a specific condition. Further, a terminal having a relatively low priority (a terminal other than a terminal of a specific user / service) may be described as a normal terminal. A normal terminal may be a terminal that does not satisfy a specific condition. In addition, these descriptions may be described together with the description showing an example of the type of terminal such as the managed terminal and the LoRa terminal. In the following, an example of channel allocation to two types of terminals, a terminal of a specific user / service and a normal terminal, is shown, but the present disclosure is not limited to this. For example, three or more priorities may be set, and different channel allocations may be executed for three or more terminals.

For example, a terminal owned by a specific user and providing a specific service, a terminal owned by a specific user and providing a service that is not a specific service, and a terminal owned by a user other than the specific user and providing a specific service. Different priorities may be set for the terminal.

Further, for example, when the number of terminals providing a specific service is a predetermined number or more, among the terminals providing a specific service, the terminal owned by the specific user is a terminal having a relatively high priority. It may be there. In this case, when the number of terminals providing a specific service is less than a predetermined number, each of the terminals providing a specific service is a terminal having a relatively high priority regardless of the owner of the terminal. good.

<Variation 5-1 of channel allocation>
FIG. 30 is a diagram showing an example of variation 5-1 of channel allocation. The horizontal axis and the vertical axis of FIG. 30 are the same as those of FIG.

In variation 5-1 of channel allocation, the base station 100 allocates a terminal of a specific user / service to the LoRa channel among the managed LoRa terminals to be allocated. Further, the base station 100 allocates a terminal of a specific user / service to the Wi-SUN channel among the managed Wi-SUN terminals to be allocated.

In variation 5-1 of channel allocation, the base station 100 selects the managed LoRa terminal having a relatively small GW reception power among the managed LoRa terminals to be allocated excluding the terminal of the specific user / service, in the LoRa channel. The managed LoRa terminal, which has a relatively large GW reception power, is assigned to the shared channel. Here, the method of determining the managed LoRa terminal to be assigned to the LoRa channel and the shared channel may be the same as the method shown with reference to FIG.

In variation 5-1 of channel allocation, the base station 100 is a managed Wi-SUN terminal having a relatively small GW reception power among the managed Wi-SUN terminals to be allocated excluding terminals of specific users / services. Is assigned to the Wi-SUN channel, and among the managed Wi-SUN terminals to be allocated, the managed Wi-SUN terminal having a relatively large GW received power is assigned to the shared channel. Here, the method of determining the managed Wi-SUN terminal to be assigned to the Wi-SUN channel and the shared channel may be the same as the method shown with reference to FIG.

<Flow of variation 5-1 of channel allocation>
FIG. 31 is an example of a flowchart of variation 5-1 of channel allocation. In FIG. 31, the same processing as in FIG. 5 is assigned the same reference numeral and the description thereof will be omitted.

In the flowchart shown in FIG. 31, when the communication method used by the terminal z is Wi-SUN (YES in S103), the base station 100 determines whether or not the terminal z is a terminal of a specific user / service (YES in S103). S1201).

When the terminal z is a terminal of a specific user / service (YES in S1201), the base station 100 allocates the terminal z to the Wi-SUN channel (S106). Then, the process of S102 is executed.

When the terminal z is not a terminal of a specific user / service (NO in S1201), the process of S104 is executed.

Further, in the flowchart shown in FIG. 31, when the communication method used by the terminal z is not Wi-SUN (NO in S103), the base station 100 determines whether or not the terminal z is a terminal of a specific user / service. Judgment (S1202).

When the terminal z is a terminal of a specific user / service (YES in S1202), the base station 100 allocates the terminal z to the LoRa channel (S110). Then, the process of S111 is executed.

When the terminal z is not a terminal of a specific user / service (NO in S1202), the process of S107 is executed.

The transmission power control process (S109 and S111) in the flowchart shown in FIG. 31 is an example, and the present disclosure is not limited to this. For example, S111 in FIG. 31 may be replaced with S202 in FIG. Alternatively, after the processing of S109 and S111 in FIG. 31, the processing of S301 and S302 may be performed in the same manner as in FIG. The present invention is not limited to these, and may be combined with other examples of transmission power control described above, or may be replaced with other examples of transmission power control described above. Alternatively, the processes of S109 and S111 do not have to be executed. Alternatively, transmission power control different from that of a normal terminal may be performed on a terminal of a specific user / service. An example of this transmission power control will be described later.

The variation 5-1 of the channel allocation described above can improve the communication quality for the user's terminal and / or service for which better communication quality is desired. As a result, for example, the terminals of the elderly and children can communicate with better communication quality, so that the function of the terminals can be avoided from being temporarily stopped due to the disconnection of the communication, and the terminals of the elderly and children can be prevented from being temporarily stopped. It is possible to strengthen watching.

In the example of FIG. 30, the terminal of the specific user / service is assigned to the LoRa channel or the Wi-SUN channel for each GW regardless of the magnitude of the received power, but the present disclosure is not limited to this. .. The managed LoRa terminal of the specific user / service having a relatively large GW received power is assigned to the shared channel, and the managed LoRa terminal of the specific user / service having a relatively small GW received power is assigned to the LoRa channel. good. In this case, the conditions for the managed LoRa terminal of the specific user / service assigned to the shared channel may be stricter than the conditions for the normal managed LoRa terminal assigned to the shared channel. For example, when allocating to a shared channel or assigning to a LoRa channel is determined using a comparison between the GW received power and the threshold value, the threshold value compared with the GW received power of the LoRa terminal within the management of a specific user / service is usually It may be larger than the threshold value compared with the GW received power of the LoRa terminal within the management of.

<Variation of channel allocation 5-2>
In the variation 5-1 described above, an example of determining a channel to be assigned to a terminal of a specific user / service from the LoRa channel, Wi-SUN channel, and shared channel is shown. In variation 5-2, as in variation 4 described above, "LoRaCG" containing one or more LoRa channels, "Wi-SUNCG" containing one or more Wi-SUN channels, and "shared CG" containing one or more shared channels. In each of the above, an example of determining the channel to be assigned to the terminal of a specific user / service is shown.

In the following, an example of determining a channel to be assigned to each of the managed terminals from a plurality of channels included in the shared CG will be described.

FIG. 32 is a diagram showing an example of variation 5-2 of channel allocation. The horizontal axis and the vertical axis of FIG. 32 are the same as those of FIG. 23. Further, the level of the usage status of the unmanaged terminals in each of the four channels (channels # C ₁ to # C ₄ ) is the same as in FIG. 23. Further, FIG. 32 shows n + z managed terminals assigned to any of channels # C ₁ , # C ₂ , # C ₃ , and # C ₄ .

Further, in FIG. 32, as in FIG. 23, channels # C ₁ and # C ₂ are classified as “channels with small unmanaged interference”, and channels # C ₃ are classified as “channels with large unmanaged interference”. Will be done. Further, since channel # C ₄ is close to the upper limit value α of the usage status level, it may correspond to “a channel to which an in-managed terminal is not assigned”.

The base station 100 allocates a channel with less unmanaged interference to the terminal of a specific user / service among the terminals within management. In FIG. 32, terminals # 1 to # z of specific users / services are assigned to channels # C ₁ and # C ₂ with less unmanaged interference.

Then, the base station 100 rearranges n managed terminals (in other words, "normal managed terminals") that are not terminals of a specific user / service in the order of RSSI. Then, as in FIG. 23, the base station 100 decides to allocate channels # C ₁ and # C ₂ with small unmanaged interference to the managed terminals # 1 to # m corresponding to the relatively small RSSI. It is determined that the managed terminals # m + 1 to # n corresponding to the relatively large RSSI are assigned to the channel # C ₃ having a large unmanaged interference. Here, m is, for example, the ratio of the availability of channels # C ₁ and # C ₂ after allocating z specific users / services within the management terminal to the availability of channel # C ₃ . May be determined based on.

Note that FIG. 32 shows an example of determining a channel to be assigned to each of the managed terminals from a plurality of channels included in the shared CG, as in FIG. 23, but for Wi-SUNCG and LoRaCG. However, it may be applied in the same manner. For example, if channels # C ₁ , # C ₂ , # C ₃ , and # C ₄ are Wi-SUNCG channels, n + z managed terminals are determined to be assigned to Wi-SUNCG. It is a SUN terminal. Further, for example, when channels # C ₁ to # C ₄ are LoRaCG channels, the n managed terminals are managed LoRa terminals determined to be assigned to LoRaCG.

<Flow of variation 5-2 of channel allocation>
Next, the processing flow of variation 5-2 will be described. The processing flow of variation 5-2 is the same as that of variation 4-1 shown in FIG. 24, but the processing of S806 in FIG. 24 is different from that of variation 4-1.

FIG. 33 is an example of a flowchart corresponding to variation 5-2 executed in S806 of FIG. 24. In FIG. 33, the same processing as in FIG. 25 is assigned the same reference numeral and the description thereof will be omitted. In the flow of FIG. 33, the process of S901 in FIG. 25 is replaced with the process of S1301 to S1304.

The base station 100 determines whether or not the confirmation regarding the specific user / service has been completed among the terminals to be assigned (S1301).

When the confirmation is not completed (NO in S1301), that is, when there is a terminal (hereinafter referred to as "terminal y") for which confirmation regarding a specific user / service has not been completed among the terminals to be assigned. , The base station 100 executes the confirmation process after S1302 for the terminal y.

The base station 100 determines whether or not the terminal y is a specific user / service (S1302).

When the terminal y is not a specific user / service (NO in S1302), the confirmation of the terminal y is completed, and the process of S1301 is executed.

When the terminal y is a specific user / service (YES in S1302), the base station 100 allocates the terminal y to a channel with less unmanaged interference (S1303). Then, the process of S1301 is executed.

When the confirmation is completed (YES in S1301), the base station 100 targets the terminals excluding the terminals for which channel allocation has been completed in S1303, and sorts the terminals in ascending order of RSSI of each allocation target (YES in S1301). S1304). Then, the processing after S902 is executed. The case where the confirmation is completed (YES in S1301) corresponds to the case where there is no terminal for which the confirmation regarding the specific user / service has not been completed among the terminals to be assigned.

It was explained that the processing flow of variation 5-2 is the same as that of variation 4-1 shown in FIG. 24, except that the processing of S806 in FIG. 24 is changed to the flowchart shown in FIG. However, this disclosure is not limited to this. For example, the transmission power control process (S109 and S111) in the flowchart shown in FIG. 24 is an example, and the transmission power control process in the process flow of variation 5-2 is not limited to the example of FIG. 24. For example, S111 in FIG. 24 in the processing flow of variation 5-2 may be replaced with S202 in FIG. Alternatively, after the processing of S109 and S111 in FIG. 24, the processing of S301 and S302 may be performed in the same manner as in FIG. The present invention is not limited to these, and may be combined with other examples of transmission power control described above, or may be replaced with other examples of transmission power control described above. Alternatively, the processes of S109 and S111 do not have to be executed. Alternatively, transmission power control different from that of a normal terminal may be performed on a terminal of a specific user / service. An example of this transmission power control will be described later.

According to the variation 5-2 described above, even when the terminal of a specific user / service is assigned to the shared channel, the communication quality for the terminal and / or the service of the user who wants better communication quality can be improved. As a result, for example, the terminals of the elderly and children can communicate with better communication quality, so that the function of the terminals can be avoided from being temporarily stopped due to the disconnection of the communication, and the terminals of the elderly and children can be prevented from being temporarily stopped. It is possible to strengthen watching.

<Variations of channel allocation 5-3>
In Variation 5-2, an example in which the types of managed terminals are not distinguished is shown, but the present disclosure is not limited to this. Variation 5-3 shows an example in which the managed LoRa terminal and the managed Wi-SUN terminal exist in the managed terminal. Variation 5-3 is applied to the shared channel to which both the LoRa terminal and the Wi-SUN terminal are assigned.

FIG. 34 is a diagram showing an example of variation 5-3 of channel allocation. The horizontal axis and the vertical axis of FIG. 34 are the same as those of FIG. 23. Further, the level of the usage status of the unmanaged terminals in each of the four channels (channels # C ₁ to # C ₄ ) is the same as in FIG. 23. However, since variation 5-3 is applied to the shared channel, each of the four channels is a shared channel.

Further, FIG. 34 shows z + x + n managed terminals assigned to any of channels # C ₁ , # C ₂ , # C ₃ , and # C ₄ . Here, the z + x + n managed terminals are a managed Wi-SUN terminal or a managed LoRa terminal, respectively.

Further, in FIG. 34, similarly to FIG. 23, channels # C ₁ and # C ₂ are classified as “channels with small unmanaged interference”, and channels # C ₃ are classified as “channels with large unmanaged interference”. Will be done. Further, since channel # C ₄ is close to the upper limit value α of the usage status level, it may correspond to “a channel to which an in-managed terminal is not assigned”.

The base station 100 allocates a channel with less unmanaged interference to the terminal of a specific user / service among the terminals within management. In FIG. 34, terminals # 1 to # z of specific users / services are assigned to channels # C ₁ and # C ₂ with less unmanaged interference. Here, the terminal of the specific user / service may include a LoRa terminal in management and a Wi-SUN terminal in management.

Among the managed terminals, the base station 100 allocates the managed Wi-SUN terminal (abbreviated as “managed Wi-SUN” in FIG. 34) to the channel with less unmanaged interference. In FIG. 34, the managed Wi-SUN terminals # 1 to # x are assigned to channels with less unmanaged interference.

Then, the base station 100 rearranges the managed LoRa terminals (abbreviated as “managed LoRa” in FIG. 34) in the order of RSSI. Similar to FIG. 23, the base station 100 determines that the managed LoRa terminals # 1 to # m corresponding to the relatively small RSSI are assigned to the channels # C ₁ and # C ₂ having less unmanaged interference, and compares them. It is determined that channels # C ₃ and # C ₄ having large unmanaged interference are assigned to the managed LoRa terminals # m + 1 to # n corresponding to the large RSSI. Here, m is, for example, the availability of channels # C ₁ and # C ₂ after allocating z specific user / service terminals and x managed Wi-SUN terminals, and channel # C. It may be determined based on the ratio of the availability to ₃ .

In the above, the example in which the priority of the terminal of the specific user / service is the highest, the priority of the Wi-SUN terminal in the management is high, and the priority of the normal LoRa terminal in the management is the lowest is shown. , The present disclosure is not limited to this.

According to the variation 5-3 described above, even when the terminal of a specific user / service is assigned to the shared channel, the communication quality for the terminal and / or the service of the user who desires better communication quality can be improved. As a result, for example, the terminals of the elderly and children can communicate with better communication quality, so that the function of the terminals can be avoided from being temporarily stopped due to the disconnection of the communication, and the terminals of the elderly and children can be prevented from being temporarily stopped. It is possible to strengthen watching. Further, the variation 5-3 can improve the communication quality of the Wi-SUN method, which has a weaker error tolerance than the LoRa method.

<Example of transmission power control of variation 5-1>
Next, another example of transmission power control in the channel allocation of variation 5-1 described above will be described. FIG. 35 is a diagram showing an example of transmission power control for the channel allocation shown in FIG. The horizontal axis and the vertical axis of FIG. 35 are the same as those of FIG. Further, since the allocation of the managed terminal to each channel is the same as the example shown in FIG. 30, the description thereof will be omitted.

The transmission power control for a normal managed LoRa terminal (a managed LoRa terminal that is not a terminal of a specific user / service) assigned to the shared channel and the LoRa channel is the same as the third example shown in FIG.

The base station 100 controls the transmission power of either (i) or (ii) with respect to the LoRa terminal in the management of the specific user / service assigned to the LoRa channel. (I) is an option of not performing the first transmission power control and the second transmission power control. In other words, (i) is an option of control for communication with the maximum transmission power. (Ii) is an option of performing the second transmission power control. The base station 100 may select either (i) or (ii) based on the result of environmental monitoring. For example, the base station 100 may select (i) if unmanaged interference is dominant as a result of environmental monitoring on the LoRa channel, and select (ii) if internal interference is not dominant.

Next, the flow of processing related to the transmission power control shown in FIG. 35 will be described. FIG. 36 is an example of a flowchart relating to the transmission power control shown in FIG. 35. The processing flow shown in FIG. 36 is a processing flow for determining transmission power control for the managed LoRa terminal assigned to the LoRa channel. For example, the process flow shown in FIG. 36 may be, for example, a process replaced with S111 in FIG. 31. Hereinafter, the terminal subject to transmission power control will be referred to as terminal z, as in the example of FIG. 31.

The base station 100 determines whether or not the terminal z is a terminal of a specific user / service (S1401).

When the terminal z is not a terminal of a specific user / service (NO in S1401), the base station 100 determines whether or not unmanaged interference is dominant in the LoRa channel assigned to the terminal z (S1402).

When unmanaged interference is dominant (YES in S1402), the base station 100 does not perform the first transmission power control with respect to the terminal z (first transmission power control: OFF) (S1403).

When the unmanaged interference is not dominant (NO in S1402), the base station 100 performs the first transmission power control with respect to the terminal z (first transmission power control: ON) (S1404). Here, the base station 100 does not have to perform the difference correction for each communication method in the first transmission power control of S1404.

The base station 100 performs a second transmission power control for the terminal z (second transmission power control: ON) (S1405). Then, the flow shown in FIG. 36 ends. As a result, the base station 100 can execute the first transmission power control for the managed LoRa terminal assigned to the LoRa channel in which unmanaged interference is dominant among the managed LoRa terminals that are not specific users / services. Instead, the second transmission power control is executed. Further, the base station 100 has a first transmission power without difference correction with respect to the managed LoRa terminal assigned to the LoRa channel in which unmanaged interference is not dominant among the managed LoRa terminals that are not specific users / services. The control and the second transmission power control are executed.

When the terminal z is a terminal of a specific user / service (YES in S1401), the base station 100 does not perform the first transmission power control for the terminal z (first transmission power control: OFF) (S1406). ..

The base station 100 does not perform the second transmission power control for the terminal z (second transmission power control: OFF) (S1407). Alternatively, the base station 100 performs a second transmission power control with respect to the terminal z (second transmission power control: ON). Then, the flow shown in FIG. 36 ends.

In the processing of S1406 and S1407, there are two types of transmission power: an example in which the first transmission power control and the second transmission power control are not performed, and an example in which the first transmission power control is not performed and the second transmission power control is performed. An example of control is shown. Of the two types of transmission power control, the transmission power control executed by the base station 100 with respect to the terminal z may be fixed to either one. Alternatively, these two transmission power controls may be randomly selected. For example, the transmission power control may be randomly determined for each terminal, or the common transmission power control may be randomly determined between the terminals. Alternatively, it may be determined according to the unmanaged interference of the LoRa channel assigned to the terminal.

In the example of the transmission power control of the variation 5-1 described above, the transmission power control of the terminal of the specific user / service assigned to the LoRa channel is performed. As a result, for example, the transmission power of the terminal of the specific user / service assigned to the LoRa channel is set higher than the transmission power of the normal terminal assigned to the LoRa channel, so that the communication of the LoRa terminal within the management of the specific user / service is set. The characteristics can be improved. Further, for example, in the terminal of the specific user / service, the transmission power control is performed based on the diffusion rate of the LoRa method, so that the communication characteristics of the LoRa terminal within the management of the specific user / service can be further improved.

<Example of transmission power control of variation 5-2>
Next, another example of transmission power control in the channel allocation of variation 5-2 described above will be described. FIG. 37 is a diagram showing an example of transmission power control for the channel allocation shown in FIG. 32. The horizontal axis and the vertical axis of FIG. 37 are the same as those of FIG. 23. Further, since the allocation of the managed terminal to each channel is the same as the example shown in FIG. 32, the description thereof will be omitted. Further, FIG. 37 shows an example in which channels # C ₁ , # C ₂ , # C ₃ , and # C ₄ are shared channels.

For example, in FIG. 37, the base station 100 performs a first transmission power control (first transmission power control: ON) for a normal managed LoRa terminal that is not a managed LoRa terminal of a specific user / service, and the first transmission power control is performed. 2 Perform transmission power control (second transmission power control: ON). In the first transmission power control for the managed LoRa terminal assigned to the shared channel, the target value may be set to a relatively high value as in the first example.

Then, the base station 100 controls the transmission power of either (i) or (ii) with respect to the LoRa terminal within the management of the specific user / service. (I) is an option of not performing the first transmission power control and the second transmission power control. In other words, (i) is an option of control for communicating with the maximum transmission power. (Ii) is an option of performing the second transmission power control without performing the first transmission power control. The base station 100 may select either (i) or (ii) based on the result of environmental monitoring. For example, the base station 100 may select (i) if uncontrolled interference is dominant as a result of environmental monitoring on the LoRa channel, and select (ii) if uncontrolled interference is not dominant.

Next, the flow of processing related to the transmission power control shown in FIG. 37 will be described. FIG. 38 is an example of a flowchart relating to the transmission power control shown in FIG. 37. The processing flow shown in FIG. 38 is a processing flow for determining transmission power control for the managed LoRa terminal assigned to the shared channel. For example, the process flow shown in FIG. 38 may be executed, for example, after FIG. 33. Hereinafter, the terminal subject to transmission power control will be referred to as terminal y, as in the example of FIG. 33.

The base station 100 determines whether or not the terminal y is a terminal of a specific user / service (S1501).

When the terminal y is not a terminal of a specific user / service (NO in S1501), the base station 100 performs a first transmission power control with respect to the terminal y (first transmission power control: ON) (S1502).

The base station 100 performs a second transmission power control for the terminal y (second transmission power control: ON) (S1503). Then, the flow shown in FIG. 38 ends. As a result, the base station 100 executes the first transmission power control and the second transmission power control for the managed LoRa terminal that is not a specific user / service.

When the terminal y is a terminal of a specific user / service (YES in S1501), the base station 100 does not perform the first transmission power control with respect to the terminal y (first transmission power control: OFF) (S1504). ..

The base station 100 does not perform the second transmission power control for the terminal y (second transmission power control: OFF) (S1505). Alternatively, the base station 100 performs a second transmission power control with respect to the terminal y (second transmission power control: ON). Then, the flow shown in FIG. 38 ends.

In the processing of S1504 and S1505, there are two types of transmission power: an example in which the first transmission power control and the second transmission power control are not performed, and an example in which the first transmission power control is not performed and the second transmission power control is performed. An example of control is shown. Of the two types of transmission power control, the transmission power control executed by the base station 100 with respect to the terminal y may be fixed to either one. Alternatively, these two transmission power controls may be randomly selected. For example, the transmission power control may be randomly determined for each terminal, or the common transmission power control may be randomly determined between the terminals. Alternatively, it may be determined according to the unmanaged interference of the shared channel assigned to the terminal.

According to the example of the transmission power control of the variation 5-2 described above, the transmission power control of the terminal of the specific user / service assigned to the shared channel is performed. As a result, for example, the transmission power of the terminal of the specific user / service assigned to the shared channel is set higher than the transmission power of the normal terminal assigned to the shared channel, so that the communication of the LoRa terminal within the management of the specific user / service is set. The characteristics can be improved. Further, for example, in the terminal of the specific user / service, the transmission power control is performed based on the diffusion rate of the LoRa method, so that the communication characteristics of the LoRa terminal within the management of the specific user / service can be further improved.

In each of the above-mentioned examples, the downlink signal (for example, feedback information) transmitted to the managed LoRa terminal assigned to the LoRa channel may be transmitted in the LoRa channel. Further, the downlink signal (for example, feedback information) transmitted to the managed Wi-SUN terminal assigned to the Wi-SUN channel may be transmitted in the Wi-SUN channel.

Further, in each of the above-mentioned examples, the downlink signal (for example, feedback information) transmitted to the managed terminal assigned to the channel with relatively small unmanaged interference may be transmitted in the channel.

It should be noted that the terminal of the specific user / service may always be assigned a channel capable of higher quality communication than the normal terminal. Alternatively, it may be variably determined whether or not to allocate a channel capable of communication with higher quality than a normal terminal to the terminal of a specific user / service. For example, a specific user / service terminal owned by a child with a lot of dangerous behavior history can communicate with high quality while the child is in an area where an accident is likely to occur (eg near a road). Channel is assigned. In this case, the terminal of the specific user / service is not assigned a channel capable of high-quality communication while the child is in an area where an accident is unlikely to occur (for example, in the child's home). It's okay. That is, in this case, the terminal may be treated in the same way as a normal terminal. Further, if the number of people existing in the corresponding area is less than a predetermined number, a channel capable of high-quality communication is assigned to the terminal of a person in the mountains or at sea. In this case, if the number of people existing in the area is more than the specified number and / or if there is a rescue team in the area, the terminal of the person existing in the area can communicate with high quality. Does not have to be assigned.

For example, when the number of terminals of a specific user / service is large (for example, when the number is a predetermined number or more), a terminal having a higher priority may be set from the terminals of the specific user / service. For example, among the terminals of a specific user / service owned by the elderly, the terminal owned by the elderly who is in poor physical condition may be set as a terminal having a higher priority than other terminals. In this case, a terminal capable of high-quality communication may be preferentially assigned to a terminal having a higher priority than other terminals. Further, in this case, the terminal having a low priority may be assigned a channel having a relatively small unmanaged interference among the remaining channels.

A terminal requesting preferential allocation to the LoRa channel or Wi-SUN channel displays information indicating the request (allocation request) before starting communication (for example, when the terminal is started, when a connection is established, etc.). It may notify the base station (or the server via the base station). For example, this notification may be executed by a higher layer message. Further, in this case, the terminal may notify the detailed user information of the owner. Detailed user information includes, for example, at least one of age, family structure and medical condition. Detailed user information may be notified only for the first time or periodically. When the detailed user information is notified only for the first time, the allocation request and the user ID may be notified from the second time onward. By such a notification, it is possible to prevent the terminal of the user who is not originally prioritized from being illegally and preferentially assigned, and to prevent unauthorized use.

In the diffusion rate allocation control, a relatively large diffusion rate may be assigned to a terminal of a specific user / service. Here, when the number of terminals of the specific user / service is a predetermined number or more, the relatively large diffusion rate may be assigned to the terminal having a higher priority among the terminals of the specific user / service. Further, it may be variably determined whether or not to allocate a relatively large diffusion rate to the terminal of a specific user / service. In addition, two or more of diffusion rate allocation, channel allocation, and transmission power control may be used in combination. Further, in each of the diffusion rate allocation, channel allocation, and transmission power control, whether or not to consider a certain terminal as a terminal of a specific user / service may be independently selected. For example, a terminal may be regarded as a specific user / service terminal in channel allocation, but may not be regarded as a specific user / service terminal in diffusion rate allocation and transmission power control.

Further, a terminal having a relatively high moving speed may have difficulty in following the control as compared with a terminal having a slow moving speed, and the RSSI may be larger than expected. In such a case, the managed LoRa terminal having a relatively high moving speed may be assigned to a channel having a relatively large unmanaged interference among the shared channels. In this case, a small diffusion rate (for example, SF7) is assigned to the managed LoRa terminal having a relatively high moving speed, and a transmission power of a predetermined value or less may be set regardless of RSSI.

The notation "... part" in the above embodiment is referred to as "... circuitry", "... device", "... unit", or "... module". It may be replaced with another notation.

Further, the notation "channel" in the above embodiment includes "frequency", "frequency channel", "band", "band", "carrier", "subcarrier", or "(frequency) resource". It may be replaced with the notation of.

The present disclosure can be realized by software, hardware, or software linked with hardware.

Each functional block used in the description of the above embodiment is partially or wholly realized as an LSI which is an integrated circuit, and each process described in the above embodiment is partially or wholly. It may be controlled by one LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of one chip so as to include a part or all of functional blocks. The LSI may include data input and output. LSIs may be referred to as ICs, system LSIs, super LSIs, and ultra LSIs depending on the degree of integration.

The method of making an integrated circuit is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Further, an FPGA (Field Programmable Gate Array) that can be programmed after the LSI is manufactured, or a reconfigurable processor that can reconfigure the connection and settings of the circuit cells inside the LSI may be used. The present disclosure may be realized as digital processing or analog processing.

Furthermore, if an integrated circuit technology that replaces an LSI appears due to advances in semiconductor technology or another technology derived from it, it is naturally possible to integrate functional blocks using that technology. The application of biotechnology may be possible.

The present disclosure can be implemented in all types of devices, devices and systems (collectively referred to as communication devices) having communication functions. Non-limiting examples of communication devices include telephones (mobile phones, smartphones, etc.), tablets, personal computers (PCs) (laptops, desktops, notebooks, etc.), cameras (digital stills / video cameras, etc.). ), Digital players (digital audio / video players, etc.), wearable devices (wearable cameras, smart watches, tracking devices, etc.), game consoles, digital book readers, telehealth telemedicines (remote health) Care / medicine prescription) devices, vehicles with communication functions or mobile transportation (automobiles, planes, ships, etc.), and combinations of the above-mentioned various devices can be mentioned.

Communication devices are not limited to those that are portable or mobile, but are all types of devices, devices, systems that are not portable or fixed, such as smart home devices (home appliances, lighting equipment, smart meters or or It also includes measuring instruments, control panels, etc.), vending machines, and any other "Things" that can exist on the IoT (Internet of Things) network.

Communication includes data communication by a cellular system, a wireless LAN system, a communication satellite system, etc., as well as data communication by a combination thereof.

Communication devices also include devices such as controllers and sensors that are connected or connected to communication devices that perform the communication functions described in the present disclosure. For example, it includes controllers and sensors that generate control and data signals used by communication devices that perform the communication functions of the communication device.

Communication devices also include infrastructure equipment that communicates with or controls these non-limiting devices, such as base stations, access points, and any other device, device, or system. ..

Although various embodiments have been described above with reference to the drawings, it goes without saying that the present disclosure is not limited to such examples. It is clear that a person skilled in the art can come up with various modifications or amendments within the scope of the claims, which naturally belong to the technical scope of the present disclosure. Understood. Further, each component in the above-described embodiment may be arbitrarily combined as long as the purpose of the disclosure is not deviated.

Although specific examples of the present disclosure have been described in detail above, these are merely examples and do not limit the scope of claims. The techniques described in the claims include various modifications and modifications of the specific examples exemplified above.

The present disclosure is suitable for wireless communication systems.

100 Base station 101 Reception unit 102, 108 Reverse diffusion unit 103 Communication quality measurement unit 104 Preamble detection unit 105 Interference classification unit 106 SF selection unit 107 Demodulation / decoding unit 109 SF extraction unit 110 SF allocation unit 111 Assignment control unit 112 Control method selection Unit 113 Transmission power setting unit 114 Control signal generation unit 115 Coding / modulation unit 116 Transmission unit

Claims (18)

A receiving unit that receives a first signal transmitted by a first terminal using a spread spectrum method and a second signal transmitted by a second terminal using a method different from the spread spectrum method.
The channel to be assigned to the first terminal is determined based on the information regarding the communication quality of the first signal, and the channel to be assigned to the second terminal is determined based on the information regarding the communication quality of the second signal. Control unit and
Equipped with
The control unit switches the transmission power control of the first terminal according to the allocation status of the second terminal in the channel assigned to the first terminal.
base station. The control unit
When the communication quality of the first signal is equal to or higher than the first threshold value, the first channel is assigned to the first terminal, and when the communication quality of the second signal is equal to or higher than the second threshold value, the first channel is assigned. Allocate the first channel to the second terminal,
When the number of the second terminals assigned to the first channel is a predetermined number or more, the control unit transfers the transmission power of the first terminal to the communication of the second signal in the first channel. Determine based on quality,
The base station according to claim 1. The control unit
When the communication quality of the first signal is less than the third threshold value, the first terminal is assigned a second channel in which the number of allocations of the second terminal is less than the specified number.
The control unit determines the transmission power of the first terminal according to the usage status of the second channel of the wireless device belonging to a network different from the network to which the base station belongs.
The base station according to claim 1. When the amount of interference from the wireless device in the second channel is less than the fourth threshold value, the control unit reduces the transmission power of the first terminal by a specified amount.
The base station according to claim 3. The control unit adjusts the transmission power of the first terminal according to the diffusion rate of the spread spectrum method used by the first terminal.
The base station according to any one of claims 2 to 4. The control unit
The first terminal whose communication is not successful within a certain time Tk is assigned to a third channel in which the number of allocations of the second terminal is less than the specified number.
The base station according to any one of claims 1 to 5. The control unit
When the first terminal assigned to the third channel succeeds in communication within the time Tk, the control unit allocates the second terminal to the fourth channel having a predetermined number or more. ,
The base station according to claim 6. The control unit includes a fifth channel for allocating the first terminal and a specified number or more of the second terminals, and a sixth channel for allocating the first terminal and a second terminal less than the specified number. Adjust the first percentage of the first terminal to be assigned to
The control unit adjusts the second ratio of the second terminal, which allocates the fifth channel and the second terminal to the seventh channel to which the first terminal is not assigned.
The control unit uses the first channel and the second ratio of the fifth channel, the sixth channel, and the seventh channel of the radio device belonging to a network different from the network to which the base station belongs. Adjust according to the situation,
The base station according to claim 1. The control unit independently sets the first ratio and the second ratio.
The base station according to claim 8. When the control unit determines to allocate a plurality of terminals including the third terminal to a group of channels to be assigned to the third terminal corresponding to either the first terminal or the second terminal, the control unit determines. Based on the information regarding the communication quality of the signal transmitted by each of the plurality of terminals, the channel to be assigned to each of the plurality of terminals is determined from the group.
The base station according to claim 1. Among the channels included in the group, the control unit selects a signal whose interference by a signal transmitted by a radio device not under the control of the base station is smaller than a predetermined value, and a signal whose received power in the base station is smaller than a predetermined power. Assign to the terminal to send,
The base station according to claim 10. The control unit interferes with a terminal whose elapsed time from the timing of the last successful communication is longer than a predetermined value by a signal transmitted by a radio device not under the control of the base station in the channels included in the group. Assign to channels smaller than the specified value,
The base station according to claim 10. When the plurality of terminals include the first terminal and the second terminal, the control unit sets the second terminal in a channel included in the group under the control of the base station. Assign to channels where interference from signals transmitted by no radio device is less than a given value,
The base station according to claim 10. Among the plurality of terminals, the control unit groups the fourth terminal, which is determined to have a higher priority of channel allocation than the terminal that does not satisfy the specific condition by satisfying the specific condition, into the group. Among the included channels, the interference caused by the signal transmitted by the radio device not under the control of the base station is assigned to the channel whose interference is smaller than the predetermined value.
The base station according to claim 10. When the fourth terminal is included in the first terminal, the control unit allocates the transmission power of the fourth terminal to the same channel as the fourth terminal, and excludes the fourth terminal. Set higher than the transmission power of the first terminal,
The base station according to claim 14. Among the first terminals, the control unit determines that the priority of channel allocation is higher than that of the terminal that does not satisfy the specific condition by satisfying the specific condition. A fifth terminal that is assigned to a channel to which the second terminal is not assigned and is determined to have a higher priority of channel allocation than the terminal that does not satisfy the specific condition by satisfying a specific condition among the second terminals. Is assigned to a channel to which the first terminal is not assigned.
The base station according to claim 1. The control unit allocates the transmission power of the fourth terminal to the same channel as the fourth terminal, and sets it higher than the transmission power of the first terminal excluding the fourth terminal.
The base station according to claim 16. The first signal transmitted by the first terminal using the spread spectrum method and the second signal transmitted by the second terminal using a method different from the spread spectrum method are received.
Based on the information regarding the communication quality of the first signal, the channel to be assigned to the first terminal is determined.
Based on the information regarding the communication quality of the second signal, the channel to be assigned to the second terminal is determined.
The transmission power control of the first terminal is switched according to the allocation status of the second terminal in the channel assigned to the first terminal.
Control method.

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