JP5986475B2 - Mobile communication system - Google Patents

Description

  The present invention relates to a mobile communication system that notifies sensor information measured by a mobile communication terminal to a server that provides a service via a base station.

  The mobile communication terminal has a function that the user always carries and specifies the position. For this reason, the mobile communication terminal is used for a monitoring service for confirming the position of a child in a school or school, such as a school or a cram school, in combination with a function such as RFID (Radio Frequency Identification) (see Patent Document 1). In addition, by using various sensors such as vibration sensors and temperature sensors, individual identification of users of mobile communication terminals and analysis of the situation, safety confirmation service to confirm the safety of elderly living alone, Applications to services that provide accurate information to users in a timely manner are being made.

  In order to provide detailed services according to the status of the mobile communication terminal carrier, such as a monitoring service, safety confirmation service, information provision service, etc., the measured value measured by the sensor of the mobile communication terminal is constantly updated. It is necessary to notify the server to be provided and always capture the situation and environment of the mobile communication terminal carryer.

JP 2010-147536 A

  As a method of periodically communicating, there is a semi-persistent scheduling that assumes VoIP or the like. In the case of VoIP, VoIP packets are transmitted to and received from the call partner every 20 [ms]. In semi-persistent scheduling, a base station (eNB) assigns a band at a constant time interval (20 [ms] to 640 [ms]). On the other hand, in the case of WWW browsing, FTP, etc., a band is temporarily allocated by dynamic scheduling according to transmission / reception capacity.

  In voice calls using semi-persistent scheduling, since the user is consciously using communication, the communication unit of the mobile communication terminal is always activated until transmission / reception of the VoIP packet is completed. When semi-persistent scheduling is used to notify the sensor information to the server, the communication unit always starts up, meaning that only the time equivalent to the communication time can be used.

  On the other hand, when using dynamic scheduling and doing the same as www browsing, the communication unit of the mobile communication terminal makes an uplink bandwidth allocation request when sending sensor information to the server, and the base station (eNB) Based on the bandwidth allocation, the sensor information is sent to the server. When transmission ends and a certain time (DRX Inactivity Timer) (1 to 2560 [ms]) elapses, the communication unit enters a sleep state (DRX (Discontinuous Reception)).

  When the sensor measures and a transmission request is generated, the communication unit makes an uplink band allocation request at intermittent transmission / reception timing (On Duration). When band allocation is performed from the base station (eNB), the sensor information is sent to the server, and the sleep state of the communication unit is released. When the transmission ends and a certain time elapses, the communication unit enters a sleep state. This will be repeated.

  In the case of using dynamic scheduling, the power consumption is somewhat lower because the communication unit enters the sleep state compared to semi-persistent scheduling. However, even when dynamic scheduling is used, each time sensor information is transmitted, the communication unit is released from the sleep state, and the time until transition to the sleep state (DRX Inactivity Timer) is If it is shorter than the notification cycle, the communication unit is always activated without shifting to the sleep state, as in the case of semi-persistent scheduling, and power consumption becomes a problem.

  The present invention has been made in view of such problems, and an object of the present invention is to use a mobile communication terminal when notifying a server that provides a service of sensor information measured by the mobile communication terminal. An object of the present invention is to provide a mobile communication system that can keep power consumption low.

  To achieve the above object, the present invention provides a mobile communication system comprising a mobile communication terminal and a base station, wherein the mobile communication terminal includes a sensor, and sensor information acquired by the sensor is stored in a sleep state. In the intermittent transmission / reception period, when the CQI measurement reference signal is transmitted from the mobile communication terminal to the base station using the CQI measurement reference signal, the base station receives the received CQI measurement reference signal. The sensor information is acquired from the signal, the synchronization correction value is calculated based on the reception of the reference signal for CQI measurement, and the synchronization correction information is transmitted to the mobile communication terminal.

  It is preferable that the mobile communication terminal determines reception of sensor information from the base station with reception of uplink synchronization correction information from the base station.

  Since the base station does not handle the transmission of sensor information by the CQI measurement reference signal as the transmission of data, the mobile communication terminal returns to the sleep state when the intermittent transmission / reception period expires. Therefore, according to the present invention, when the sensor information measured by the mobile communication terminal is notified to the server via the base station, the base station and the mobile communication terminal are synchronized to shift to the sleep state even during the transmission of the sensor information. Therefore, it is possible to keep power consumption of the mobile communication terminal low without continuously transmitting sensor information without sleeping.

It is a figure which shows the structure of the mobile communication system which concerns on embodiment of this invention. It is a sequence diagram explaining operation | movement of a mobile communication terminal, a base station, and a server. It is a figure explaining the encoding method when transmitting the reference signal for CQI measurement. It is a flowchart explaining operation | movement of the encoding method.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a configuration of a mobile communication system according to an embodiment of the present invention. A mobile communication terminal (UE) 11 carried by a user 1 is wirelessly connected to a base station (eNB) 12. The measurement value measured by the sensor of the mobile communication terminal (UE) 11 is notified to the server 13 via the base station (eNB) 12 and the network 19. The server 13 analyzes the received sensor information based on the service content set for the mobile communication terminal (UE) 11. For example, if the set service content is a watch service at a child's attending school, if it is determined that the received location information is outside the assumed area, the notification destination (the child To parents, police, etc.). Here, the sensors are, for example, various sensors that measure peripheral information, position information, human body information, and the like. The mobile communication terminal (UE) 11 is an information terminal such as a mobile phone or a smartphone.

  FIG. 2 is a sequence diagram illustrating operations of the mobile communication terminal, the base station, and the server. In connection of UM Entity of mobile communication terminal 11, when QoS information from PCRF (Policy and Charging Rules Function) is sensor information, base station 12 is in a sleep state based on transmission interval Tsns accompanying sensor information. A sleep interval (DRX Cycle = Tsns) and an intermittent transmission / reception period (On duration) are determined.

  When there is sensor information to be transmitted during the intermittent transmission / reception period (On-Duration) when the mobile communication terminal 11 is in the sleep state, the mobile communication terminal 11 bases the sensor information on the CQI measurement reference signal (Sound Reference Signal). Send to station 12. The base station 12 acquires sensor information from the received CQI measurement reference signal, and sends user data (Entity QoS = sensor information) to the server 13. Since the base station 12 does not handle the transmission of sensor information by the reference signal for CQI measurement from the mobile communication terminal 11 as the transmission of data, the mobile communication terminal 11 that is the target when the intermittent transmission / reception period (On Duration) expires. Is determined to have entered the sleep state.

  Also, the base station 12 calculates an uplink synchronization correction value based on the reception of the CQI measurement reference signal, sends a Timing Advance Command MAC Control Element to the mobile communication terminal 11, and instructs synchronization correction. When receiving the Timing Advance Command MAC Control Element, the mobile communication terminal 11 performs uplink synchronization correction. In addition, the mobile communication terminal 11 determines that the sensor information has reached the base station 12 upon receipt of the Timing Advance Command MAC Control Element.

  FIG. 3 is a diagram for explaining an encoding method when a CQI measurement reference signal is transmitted. In FIG. 3, the portable communication terminal 11 uses two different codes (A, B) when transmitting a CQI measurement reference signal (Sounding Reference Signal). When 0 is to be sent as sensor information, a signal encoded with the symbol A is sent to the base station 12, and when 1 is to be sent, a signal encoded with the symbol B is sent to the base station 12. When it is desired to send a stop bit, the signal is encoded with code A and code B, and the combined signal is sent to the base station 12.

  FIG. 4 is a flowchart for explaining the operation of the encoding method. In FIG. 4, a case where sensor information to be transmitted is 8 bits will be described. When acquiring the sensor information (S100), the mobile communication terminal 11 sets the number of transmission bits to 0 (S101). Next, it is determined whether or not the sleep state is released (S102). When the sleep is canceled (Yes in S102), the transmission of the sensor information at the time of sleep ends. When the sleep state is continued (No in S102), it is determined whether it is the transmission timing of the sensor information (S103). If it is the transmission timing (Yes in S103), it is determined whether the number of transmission bits is 8 (S104). If the number of transmission bits is 8 (Yes in S104), 8 bits are transmitted. Since it is finished, send a stop bit. The signal encoded with the code A and the code B and transmitted is sent to the base station (S111).

  If the number of transmission bits is not 8 (less than 8) (No in S104), the value of the transmission bit is confirmed (S105). When the value of the transmission bit is 1 (Yes in S105), the signal encoded with the code B is sent to the base station 12 (S110). On the other hand, when the value of the transmission bit is 0 (No in S105), the signal encoded with the code A is sent to the base station 12 (S106).

  After transmission, when synchronization correction (Timing Advance Command MAC Control Element) is received (Yes in S107), the number of transmission bits is updated (+1) (S108). If the number of transmitted bits is greater than 8 (Yes in S109), the sensor information is updated because the stop bit has been transmitted. When the number of transmission bits is 8 or less (No in S109), it prepares for the transmission timing of the next bit. If no synchronization correction is received (when a certain period of time has elapsed) (No in S107), it is determined that transmission has failed, and transmission of the same bit value is attempted again at the next transmission timing.

  As described above, since the base station does not handle the transmission of sensor information by the reference signal for CQI measurement as the transmission of data, when the intermittent transmission / reception period expires, the mobile communication terminal returns to the sleep state. Therefore, according to the present invention, even during the transmission of sensor information, the base station and the mobile communication terminal shift to sleep so that they can be synchronized and resumed. Compared to the normal sleep state, the mobile communication terminal consumes a lot of power for the transmission and reception of sensor information during the intermittent transmission and reception period, but keeps the power consumption low compared to the case of using semi-persistent scheduling and dynamic scheduling. Is possible.

1 User 11 Mobile Communication Terminal 12 Base Station 13 Server 19 Network

Claims (2)

In a mobile communication system composed of a mobile communication terminal and a base station,
The mobile communication terminal has a sensor, and transmits sensor information acquired by the sensor to the base station using a reference signal for CQI measurement in an intermittent transmission / reception period in a sleep state,
When the base station receives a CQI measurement reference signal from the mobile communication terminal, the base station acquires sensor information from the received CQI measurement reference signal, and synchronizes based on reception of the CQI measurement reference signal. A mobile communication system characterized by calculating a correction value and sending synchronization correction information to the mobile communication terminal.   2. The mobile communication system according to claim 1, wherein the mobile communication terminal determines reception of sensor information from a base station upon reception of uplink synchronization correction information from the base station.

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