KR20220079399A - Electronic device performing inteference cancellation and operating method thereof - Google Patents

Abstract

In order to achieve the above object, a method of operating an electronic device supporting dynamic spectrum sharing (DSS) according to an exemplary embodiment of the present disclosure includes performing a radio resource control (RRC) connection with a serving base station, the Receiving information for interference cancellation from a serving base station, receiving a cell specific reference signal (CRS) from at least one neighboring base station different from the serving base station, and interference based on the CRS and the information for interference cancellation performing removal.

Description

ELECTRONIC DEVICE PERFORMING INTEFERENCE CANCELLATION AND OPERATING METHOD THEREOF

The technical idea of the present disclosure relates to an electronic device, and more particularly, to an electronic device for performing interference cancellation and an operating method thereof.

Efforts are being made to develop an improved 5th generation (5G) communication system or a pre-5G communication system in order to meet the increasing demand for wireless data traffic after commercialization of the 4G (4th generation) communication system. For this reason, the 5G communication system or the pre-5G communication system is called a 4G network after (Beyond 4G Network) communication system or an LTE (Long Term Evolution) system after (Post LTE) system.

In order to achieve a high data rate, the 5G communication system is being considered for implementation in a very high frequency (mmWave) band (eg, such as a 60 gigabyte (60 GHz) band). In order to alleviate the path loss of radio waves and increase the propagation distance of radio waves in the ultra-high frequency band, in the 5G communication system, beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO) are used. ), array antenna, analog beamforming, digital beamforming, hybrid beamforming, and large scale antenna technologies are being discussed.

The technical idea of the present disclosure provides an electronic device that effectively performs CRS interference cancellation and an operating method thereof.

In order to achieve the above object, a method of operating an electronic device supporting dynamic spectrum sharing (DSS) according to an exemplary embodiment of the present disclosure includes performing a radio resource control (RRC) connection with a serving base station, the Receiving information for interference cancellation from a serving base station, receiving a cell specific reference signal (CRS) from at least one neighboring base station different from the serving base station, and interference based on the CRS and the information for interference cancellation performing removal.

In order to achieve the above object, an electronic device according to an exemplary embodiment of the present disclosure receives information for interference cancellation from a serving base station supporting 5G and LTE at the same time, and at least one neighbor supporting LTE A communication unit for receiving a cell specific reference signal (CRS) from a base station, a storage unit for storing predefined threshold information, and a radio resource control (RRC) connection with the serving base station, and information for the CRS and the interference cancellation It may include a control unit for controlling to perform interference cancellation based on the.

According to a terminal device and an operating method thereof according to an exemplary embodiment of the present disclosure, it is possible to improve reception performance of a 5G terminal by effectively performing interference cancellation on a CRS signal of an adjacent LTE base station.

1 illustrates a wireless communication system according to an exemplary embodiment of the present disclosure.
2 is a block diagram of a base station according to exemplary embodiments of the present disclosure.
3 is a block diagram of an electronic device according to example embodiments of the present disclosure.
4A illustrates an antenna port according to exemplary embodiments of the present disclosure.
4B illustrates a receive ratio frequency (RF) chain according to exemplary embodiments of the present disclosure.
5 is a block diagram of a CRS interference cancellation circuit according to exemplary embodiments of the present disclosure.
6 is a signal exchange diagram for transmitting and receiving cell-specific information according to exemplary embodiments of the present disclosure.
7 is a flowchart illustrating an operation of an electronic device according to example embodiments of the present disclosure.
8 is a graph illustrating a change in a metric value according to a frequency according to exemplary embodiments of the present disclosure.
9 is a block diagram of a wireless communication device according to an exemplary embodiment of the present disclosure.

Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

1 illustrates a wireless communication system according to an exemplary embodiment of the present disclosure.

Referring to FIG. 1 , the wireless communication system 10 may include a serving base station 110 , an electronic device 120 , a first adjacent base station 130 , and a second adjacent base station 140 .

According to various embodiments, the serving base station 110 is a network infrastructure that provides a wireless connection to the electronic device 120 . The base station 110 may have coverage defined as a certain geographic area based on a distance capable of transmitting a signal. Base station 110, in addition to the base station (base station), 'access point (AP)', 'eNodeB (eNodeB, eNB)', '5G node (5th generation node)', 'wireless point (wireless point)' Or it may be replaced with other terms having an equivalent technical meaning.

According to various embodiments, the base station 110 may be connected to one or more 'transmission/reception points (TRP)'. The base station 110 may transmit a downlink signal or receive an uplink signal to the electronic device 120 through one or more TRPs.

According to various embodiments, the electronic device 120 is a device used by a user and may communicate with the base station 110 through a wireless channel. The electronic device 120 includes 'user equipment (UE)', 'mobile station', 'subscriber station', 'customer premises equipment' (CPE) other than a terminal. ), 'remote terminal', 'wireless terminal', or 'user device' or other terms having an equivalent technical meaning may be replaced.

According to various embodiments, the electronic device 120 and the serving base station 110 may support dynamic spectrum sharing. The serving base station 110 may transmit and receive signals through 5G NR and LTE in the same frequency band as the electronic device 120 . According to various embodiments, the first neighboring base station 130 and the second neighboring base station 140 may correspond to a base station supporting 4G LTE. The electronic device 120 may receive a downlink signal from the serving base station 110 , but signals generated from the first adjacent base station 130 and the second adjacent base station 140 at the same time cannot inevitably correspond to the noise signal. .

2 is a block diagram of a base station according to exemplary embodiments of the present disclosure.

Referring to FIG. 2 , the base station 110 may include a wireless communication unit 210 , a backhaul communication unit 220 , a storage unit 230 , and a control unit 240 .

The wireless communication unit 210 may perform functions for transmitting and receiving signals through a wireless channel. According to an embodiment, the wireless communication unit 210 may perform a function of converting a baseband signal and a bit stream according to a physical layer standard of a system. For example, when transmitting data, the wireless communication unit 210 may generate complex symbols by encoding and modulating the transmitted bit string, and upon receiving data, the received bit string may be restored by demodulating and decoding the baseband signal. have. In addition, the wireless communication unit 210 may up-convert the baseband signal into a radio frequency (RF) band signal and then transmit it through the antenna or down-convert the RF band signal received through the antenna into a baseband signal. To this end, the wireless communication unit 210 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a digital to analog converter (DAC), an analog to digital converter (ADC), and the like.

The wireless communication unit 210 may transmit and receive signals. For example, the wireless communication unit 210 may transmit a synchronization signal, a reference signal, system information, a message, control information, or data. Also, the wireless communication unit 210 may perform beamforming. The wireless communication unit 210 may apply a beamforming weight to a signal to give directionality to a signal to be transmitted/received. The wireless communication unit 210 may repeatedly transmit a signal by changing the formed beam.

The backhaul communication unit 220 provides an interface for performing communication with other nodes in the network. That is, the backhaul communication unit 220 converts a bit string transmitted from the base station 110 to another node, for example, another access node, another base station, upper node, core network, etc. into a physical signal, and is received from another node. A physical signal can be converted into a bit string.

The storage unit 230 stores data such as a basic program, an application program, and setting information for the operation of the serving base station 110 . The storage unit 230 may be configured as a volatile memory, a non-volatile memory, or a combination of a volatile memory and a non-volatile memory. For example, the storage unit 230 may include at least cell ID, LTE bandwidth, LTE center frequency location, MBSFN configuration information, and TDD configuration information of at least one or more base stations adjacent to the serving base station 110 .

The controller 240 controls operations of the base station 110 . For example, the control unit 240 transmits and receives a signal through the wireless communication unit 210 or the backhaul communication unit 220 . In addition, the control unit 240 writes and reads data in the storage unit 230 . To this end, the controller 240 may include at least one processor.

3 is a block diagram of an electronic device according to example embodiments of the present disclosure.

Referring to FIG. 3 , the electronic device 120 may include a communication unit 310 , a storage unit 320 , and a control unit 330 .

The communication unit 310 performs functions for transmitting and receiving signals through a wireless channel. For example, the communication unit 310 performs a function of converting between a baseband signal and a bit stream according to a physical layer standard of the system. For example, when transmitting data, the communication unit 310 may generate complex symbols by encoding and modulating the transmitted bit string, and upon receiving data, may restore a received bit string by demodulating and decoding a baseband signal. In addition, the communication unit 310 may up-convert the baseband signal into an RF band signal and then transmit it through the antenna or down-convert the RF band signal received through the antenna into a baseband signal. For example, the communication unit 310 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, and the like. The communication unit 310 may perform beamforming. The communication unit 310 may apply a beamforming weight to a signal to give directionality to a signal to be transmitted/received.

The communication unit 310 may transmit and receive signals. The communication unit 310 may receive a downlink signal. The downlink signal may include a synchronization signal (SS), a reference signal (RS), system information, a configuration message, control information, or downlink data. Also, the communication unit 310 may transmit an uplink signal. The uplink signal may include a random access-related signal or a reference signal (eg, a sounding reference signal (SRS), DM-RS), or uplink data.

The storage 320 may store data such as a basic program, an application program, and setting information for the operation of the electronic device 120 . The storage unit 320 may be configured as a volatile memory, a non-volatile memory, or a combination of a volatile memory and a non-volatile memory. In addition, the storage unit 320 may provide stored data according to the request of the control unit 330 .

According to various embodiments, the storage unit 320 may further include threshold value storage information. The threshold value may be a value for determining whether a CRS symbol is actually transmitted in a CRS signal received from at least one or more LTE base stations adjacent to the electronic device 120 . For example, the threshold value may be variable according to the measured strength of the CRS signal. The storage unit 320 may store a variable threshold value according to the measured strength of the CRS signal as a predefined mapping relationship.

The controller 330 may control overall operations of the electronic device 120 . For example, the control unit 330 may transmit and receive signals through the communication unit 310 . Also, the control unit 330 may write and read data in the storage unit 320 . To this end, the controller 330 may include at least one processor or microprocessor, or may be a part of the processor. In the case of a part of the processor, the part of the communication unit 310 and the control unit 330 may be referred to as a communication processor (CP).

According to an embodiment, the control unit 330 may further include an IC determination unit 335 . The IC determiner 335 may determine whether to perform interference cancellation based on at least one of a reception metric, a quality of service (QoS), and a service type. According to an embodiment, when the reception metric is less than a threshold value, the IC determination unit 335 may transmit a control signal instructing the communication unit 310 to perform interference cancellation. For example, the reception metric may include at least a reference signal received power (RSRP), a signal to interference noise ratio (SINR), a received signal strength index (RSSI), and a received signal received quality (RSRQ). According to another embodiment, when the electronic device 120 executes an application requiring a higher QoS, the IC determination unit 335 may transmit a control signal instructing to perform interference cancellation to the communication unit 310 . have. In this case, the IC decision circuit 335 may generate the control signal even if the received metric exceeds a threshold value.

4A illustrates an antenna port according to exemplary embodiments of the present disclosure.

Referring to FIG. 4A , the base station 400 and the electronic device 410 may communicate with each other using a multiple input multiple output (MIMO) scheme. To this end, each of the base station 400 and the electronic device 410 may include a plurality of antennas Ant1_1, Ant1_2, Ant2_1, and Ant2_2. In FIG. 4A , the base station 400 and the electronic device 410 each include two antennas Ant1_1, Ant1_2, Ant2_1, and Ant2_2, respectively, but the present invention is not limited thereto. It goes without saying that the technical spirit of the present disclosure may also be applied to an embodiment in which the base station 400 and the electronic device 410 each include two or more antennas.

The base station 400 may include a first transceiver 11 , a second transceiver 12 , a first antenna Ant1_1 and a second antenna Ant1_2 . The first transceiver 11 and the second transceiver 12 may each be connected to one antenna. For example, the first transceiver 11 may be connected to the first antenna Ant1_1 , and the second transceiver 12 may be connected to the second antenna Ant1_2 . When the base station 400 operates as a transmitting device, the first transceiver 11 and the second transceiver 12 may operate as a transmitter, and when the base station 400 operates as a receiving device, the first transceiver 11 and The second transceiver 12 may operate as a receiver.

The first transceiver 11 generates a first signal Sig by merging the first component carrier signal C1 and the second component signal C2 in the transmission mode, and transmits the generated first signal Sig to the electronic device. It can output to (410). The first transceiver 11 may extract not only the first component carrier C1 but also the second component carrier C2 from the first signal Sig. Considering the base station 400 and the electronic device 410 supporting dynamic spectrum sharing, the first component carrier C1 may be included in a frequency band of 5G NR, and the second component carrier C2 may be included in the LTE frequency band. may be included. According to the first technical idea of the present disclosure, each of the first transceiver 11 and the second transceiver 12 may not transmit only one component carrier signal, but may merge and transmit a plurality of component carrier signals. Instead of extracting only one component carrier signal from one signal Sig, a plurality of component carrier signals may be extracted.

The electronic device 410 may include a third transceiver 21 , a fourth transceiver 22 , a third antenna Ant2_1 , and a fourth antenna Ant2_2 . Since the electronic device 410 may be substantially the same as or similar to the base station 400 , a description thereof will be omitted.

4B illustrates a receive ratio frequency (RF) chain according to exemplary embodiments of the present disclosure.

According to various embodiments, the communication unit 310 may include a decoding and demodulation unit 450 , a digital beamforming unit 460 , a CRS interference cancellation circuit 465 , and a first reception path 470-1 to an N-th reception path. (470-N), an analog beamforming unit 480 may be included.

The decoder and demodulator 450 may perform channel decoding. For channel decoding, at least one of a low density parity check (LDPC) code, a convolution code, a polar code, and a turbo code may be used.

According to various embodiments, the digital beamformer 460 performs beamforming on a digital signal (eg, modulation symbols). To this end, the digital beamformer 460 multiplies the modulation symbols by beamforming weights. Here, the beamforming weights are used to change the magnitude and phase of a signal, and may be referred to as a 'precoding matrix', a 'precoder', or the like. The analog beamformer 480 performs beamforming on an analog signal. To this end, the digital beamformer 460 multiplies the analog signals by beamforming weights. Here, the beamforming weights are used to change the magnitude and phase of the signal.

The first reception path 470 - 1 to the Nth reception path 470 -N may convert analog signals into digital signals. To this end, each of the first reception path 470-1 to the N-th reception path 470-N includes a fast fourier transform (FFT) operator, an analog-to-digital converter, a CP remover, and a serial - It may include a parallel converter and a down converter. Specifically, each of the first receive path 470-1 to the N-th receive path 470-N down-converts a received signal to a baseband frequency, and removes the CP to generate a serial time domain baseband signal, A serial time domain baseband signal may be converted into parallel time domain signals, an FFT algorithm may be performed to generate N parallel frequency domain signals, and the parallel frequency domain signals may be converted into a sequence of modulated data symbols. That is, the first reception path 470-1 to the N-th reception path 470-N may provide an independent signal processing process for a plurality of streams generated through digital beamforming. However, depending on the implementation method, some of the components of the first reception path 470-1 to the N-th reception path 470-N may be used in common.

The CRS interference cancellation circuit 465 receives the FFT-converted frequency domain signals to extract the LTE CRS symbol, measures the signal strength through channel estimation for the LTE CRS, and if the CRS symbol exists, it is included in the received signal It is possible to remove the LTE CRS symbol. A detailed description of the CRS interference cancellation circuit 465 will be described later with reference to FIG. 5 .

5 is a block diagram of a CRS interference cancellation circuit according to exemplary embodiments of the present disclosure.

5, the CRS interference cancellation circuit 465 includes a frequency domain (FD) buffer 510, a CRS extractor 520, a CRS denoiser 530, a metric measurer 540, and an interference cancellation circuit ( 550), and may include an RE demapper (demapper) 560 .

The FD buffer 510 may receive a fast Fourier transform (FFT) signal. For example, the FD buffer 510 may receive and temporarily store the FFT-converted frequency domain signal from the first reception path 470-1 and the N-th reception path 470-N shown in FIG. 4B. have. The FFT-converted frequency domain signal may be as follows.

는 서빙 셀로부터 수신한 다운링크 신호를 나타내고,

는 인접 셀로부터 수신한 CRS 신호를 나타내고,

은 노이즈 신호를 나타낼 수 있다. 도 1을 함께 참조하면, 상기 서빙 셀은 서빙 기지국(110)에 상응하고, 인접 셀은 제1 인접 기지국(130) 및/또는 제2 인접 기지국(140)에 상응할 수 있다. 상기 노이즈 신호는, 열 잡음(thermal noise), 백색 가우시안 잡음(white Gaussian noise)을 포함할 수 있다.Y is the received signal in the frequency domain in which the received analog signal is FFT-converted,

represents a downlink signal received from the serving cell,

represents a CRS signal received from a neighboring cell,

may represent a noise signal. 1 , the serving cell may correspond to the serving base station 110 , and the adjacent cell may correspond to the first adjacent base station 130 and/or the second adjacent base station 140 . The noise signal may include thermal noise and white Gaussian noise.

According to various embodiments, the CRS extractor 520 receives the FFT-transformed reception signal Y from the FD buffer 510, and multiplies the FFT-transformed reception signal Y by the complex conjugate of the CRS signal to generate a Y' signal. have. According to various embodiments, the CRS denoizer 530 may perform channel estimation on a CRS signal. The CRS denoizer 530 may generate a y' signal by performing IFFT conversion on the Y' signal. The metric measurer 540 may receive the IFFT-converted signal y' and measure the metric. The metric may correspond to any one of SINR, RSRP, RSRQ, and RSSI. The metric measurer 540 may determine whether the CRS symbol has actually been transmitted by measuring a reception metric and performing comparison with a threshold value. The RE demapper 560 may demap a resource element (RE) for each carrier constituting the received signal.

6 is a signal exchange diagram for transmitting and receiving cell-specific information according to exemplary embodiments of the present disclosure.

6 and 1 together, in step S110 , the electronic device 120 may perform RRC connection with the serving base station 110 . In a dynamic spectrum sharing (DSS) scenario, the electronic device 120 may identify resource mapping of the LTE CRS transmitted by the serving base station 110 through the NR PDSCH received from the serving base station 110 . Referring to 3GPP TS 38.331, information transmitted from the serving base station 110 to the electronic device 120 is as follows.

RateMatchPatternLTE-CRS information element
-- ASN1START
-- TAG-RATEMATCHPATTERNLTE-CRS-START

RateMatchPatternLTE-CRS ::= SEQUENCE {
carrierFreqDL INTEGER (0..16383),
carrierBandwidthDL ENUMERATED {n6, n15, n25, n50, n75, n100, spare2, spare1},
mbsfn-SubframeConfigList EUTRA-MBSFN-SubframeConfigList OPTIONAL, -- Need M
nrofCRS-Ports ENUMERATED {n1, n2, n4},
v-Shift ENUMERATED {n0, n1, n2, n3, n4, n5}
}

LTE-CRS-PatternList-r16 ::= SEQUENCE (SIZE (1..maxLTE-CRS-Patterns-r16)) OF RateMatchPatternLTE-CRS

-- TAG-RATEMATCHPATTERNLTE-CRS-STOP
-- ASN1STOP

Referring to Table 1, the electronic device 120 may receive LTE bandwidth, LTE center frequency location, number of CRS ports, frequency shift parameter v_shift value, and MBSFN configuration information from the serving base station 110 . The electronic device 120 performs rate matching by accurately identifying a location to which a resource element of LTE CRS transmitted from the serving base station 110 RRC-connected to the electronic device 120 is mapped based on the received information. can do.

According to various embodiments, the serving base station 110 may transmit individual cell information to the electronic device 120 upon RRC connection. Individual cell information may refer to each of at least one or more base stations adjacent to the electronic device 120 . Specifically, the individual cell information may be information for the electronic device 120 to identify resource mapping of LTE CRS transmitted from a neighboring base station.

Based on the individual cell information, the serving base station 110 may transmit the LTE bandwidth of each of the adjacent base stations, the LTE center frequency location, the number of CRS ports, the frequency shift parameter v_shift value, and MBSFN setting information to the electronic device 120 . . The electronic device 120 may decode the individual cell information to identify a location to which a resource element of an LTE CRS transmitted by adjacent base stations to the electronic device 120 is mapped.

For example, referring together with FIG. 1 , the serving base station 110 is the LTE bandwidth of the first adjacent base station 130 together with the cell ID of the first adjacent base station 130 , the LTE center frequency location, the number of CRS ports, and the frequency. LTE bandwidth, LTE center frequency location, number of CRS ports, frequency shift parameters of the second adjacent base station 140 together with the shift parameter v_shift value, at least one of MBSFN setting information, and the cell ID of the second adjacent base station 140 At least one of a v_shift value and MBSFN configuration information may be transmitted.

According to various embodiments, the serving base station 110 may transmit common cell information to the electronic device 120 upon RRC connection. The common cell information may refer to information common to at least one or more base stations adjacent to the electronic device 120 . Specifically, the common cell information may be information for the electronic device 120 to identify resource mapping of LTE CRS transmitted from a neighboring base station.

Referring to the 3GPP standard, TS 36.331, RRC information for an adjacent base station is shown in Table 2 below.

MeasObjectEUTRA information element
-- ASN1START

MeasObjectEUTRA ::= SEQUENCE {
carrierFreq ARFCN-ValueEUTRA,
allowedMeasBandwidth AllowedMeasBandwidth,
presenceAntennaPort1 PresenceAntennaPort1,
NeighCellConfig NeighCellConfig,
offsetFreq Q-OffsetRange DEFAULT dB0,
-- Cell list
cellsToRemoveList CellIndexList OPTIONAL, -- Need ON
cellsToAddModList CellsToAddModList OPTIONAL, -- Need ON
-- Black list
blackCellsToRemoveList CellIndexList OPTIONAL, -- Need ON
blackCellsToAddModList BlackCellsToAddModList OPTIONAL, -- Need ON
cellForWhichToReportCGI PhysCellId OPTIONAL, -- Need ON

Referring to Table 2, the common cell information is for transmitting minimum information on neighboring base stations, and for example, may include at least AllowedMeasBandwidth information, PresenceAntennaPort1 information, and NeighCellConfig information.

The AllowedMeasBandwidth information may refer to a maximum LTE bandwidth value allowed for measurement in a frequency in which a DSS scenario is operating. PresenceAntennaPort1 information may indicate whether CRS port1 is used by adjacent base stations. NeighCellConfig information may indicate whether all MBSFN information of adjacent base stations is the same or different, or whether there is no MBSFN configuration information. Alternatively, the NeighCellConfig information may indicate whether TDD UL/DL allocation information between adjacent base stations is the same.

When the serving base station 110 transmits common cell information to the electronic device 120 , the electronic device 120 cannot identify resource mapping of CRS symbols of the LTE CRS signal transmitted from the adjacent base station. This is because, since the common cell information is the minimum information common between adjacent base stations, MBSFN configuration information and the number of CRS ports may be different between adjacent base stations. For example, when the MBSFN configuration information of the serving base station 110 and the first adjacent base station 130 is different, the CRS symbol transmitted from the first adjacent base station 130 cannot be identified.

In operation S120, the neighboring base station may broadcast the LTE CRS. A neighboring base station supporting LTE may configure a Multimedia Broadcast Single Frequency Network (MBSFN) subframe so that the serving base station 110 of 5G NR can periodically transmit a synchronization signal block.

In operation S130, the electronic device 120 may perform CRS interference cancellation. According to various embodiments, when individual cell information is received from the serving base station 110, the center frequency location for the neighboring base station, LTE bandwidth, number of CRS ports, frequency shift parameter v_shift value, MBSFN setting information is used to Interference cancellation for LTE CRS may be performed. According to various embodiments, when common cell information is received from the serving base station 110, interference cancellation for LTE CRS cannot be immediately performed based on common cell information, and the number of CRS ports and CRS symbol information are unknown. Therefore, it is necessary to determine whether the actual CRS symbol is transmitted. This will be described later with reference to FIG. 7 .

7 is a flowchart illustrating an operation of an electronic device according to example embodiments of the present disclosure.

Referring to FIG. 7 , in operation S210 , the electronic device 120 may perform RRC connection with the serving base station 110 and obtain interference cancellation information. As described above in FIG. 6 , the individual cell information includes the center frequency location, LTE bandwidth, number of CRS ports, frequency shift parameter v_shift value, MBSFN setting information for each of a plurality of base stations adjacent to the electronic device 120 . may include However, in this case, since the mapping position of the resource element of the LTE CRS received from the neighboring base stations can be accurately identified, it is not necessary to determine whether the CRS symbol is actually transmitted.

According to various embodiments, when receiving common cell information from the serving base station 110 , the electronic device 120 may not effectively perform interference cancellation of the received LTE CRS. For example, when the TDD configuration or MBSFN configuration is different between the serving base station 110 and the first adjacent base station 130 , the electronic device 120 transmits the LTE CRS transmission symbol received from the first adjacent base station 130 . You may not know information about Since information on the LTE CRS transmission symbol received from the first neighboring base station 130 is not known, it may be difficult for the electronic device 120 to perform a CRS interference cancellation operation for the first neighboring base station 130 . In addition, in the case of the number of CRS ports among common cell information, a minimum value may be indicated in all of the adjacent LTE cells. Accordingly, when the number of CRS ports of the first neighboring base station 130 is 4 and the number of CRS ports indicated by common information is 2, the electronic device ( 120), the interference cancellation of the LTE CRS broadcast may not be effective. Accordingly, the electronic device 120 may determine whether the CRS symbol is actually transmitted.

In operation S220, the electronic device 120 may extract a CRS signal and perform channel estimation on the CRS signal. Referring to FIG. 5 , the electronic device 120 FFT-converts the received analog signal and stores it in the FD buffer 510 , and a channel for the CRS signal based on the CRS extractor 520 and the CRS denoizer 530 . estimation can be performed.

In operation S230, the electronic device 120 may measure a reception metric for the CRS signal. The reception metric may correspond to any one of SINR, RSRP, RSRQ, and RSSI. The reception metric may be a value for determining whether a CRS symbol is actually transmitted from at least one or more adjacent base stations adjacent to the electronic device 120 . This is because, when CRS symbols are actually transmitted from at least one or more neighboring base stations, a reception metric such as SINR may indicate a certain size or more.

In operation S240, the electronic device 120 may determine whether the measured metric value exceeds a threshold value. The threshold value may be a value for determining whether the CRS symbol is actually transmitted. According to various embodiments, the threshold value may be variable based on a measured received metric value. For example, when the measured SINR value is small, it can be recognized that the strength of the CRS signal received by the electronic device 120 from the neighboring base station is weak. Since the strength of the CRS signal is weak, the improvement in reception performance of the electronic device 120 may be small even if interference cancellation is performed on the CRS signal. Accordingly, the threshold value may be set larger as the measured reception metric is smaller. As another example, when the measured SINR value is large, it can be seen that the strength of the CRS signal received by the electronic device 120 from the neighboring base station is large. That is, since the width of the reception performance of the electronic device 120 improved when the interference with the CRS signal is removed is large, the electronic device 120 may determine that the CRS symbol is actually transmitted by setting the threshold value variably small. have.

In operation S160, the electronic device 120 may perform interference cancellation on the CRS signal. The electronic device 120 may identify that the CRS symbol is actually transmitted. The electronic device 120 may perform interference cancellation for LTE CRS based on the value for the CRS channel estimated in operation S120 .

In operation S170, the electronic device 120 may identify that the CRS symbol has not been transmitted. Since the measured reception metric value is less than the threshold value, the electronic device 120 may determine that the CRS symbol is not actually transmitted. Since the actual CRS symbol is not transmitted, the electronic device 120 may bypass CRS interference cancellation.

In the above-described embodiment, the electronic device 120 has been described based on the operation S240 of determining whether the measured metric value exceeds the threshold value, but is not limited thereto. According to various embodiments, the electronic device 120 may test whether the CRS symbol is transmitted offline. For example, assuming that the CRS symbol is always transmitted, the electronic device 120 may bypass the operation of comparing the measured metric value with the threshold value. In this case, the electronic device 120 may use a previously obtained metric value. The electronic device 120 may omit an online test comparing the number of CRS ports, MBSFN configuration information, etc. determined according to the previously obtained metric value to the currently obtained metric value to be the same as the threshold value.

8 is a graph illustrating a change in a metric value according to frequency according to exemplary embodiments of the present disclosure.

Referring to FIG. 8 , metric values according to frequency bands are shown. The electronic device 120 may not be able to obtain information on the LTE bandwidth of the neighboring base station of Table 1 from the serving base station 110 .

In order to indirectly estimate the LTE bandwidth of a neighboring base station, the electronic device 120 may repeatedly perform metric measurement from a low LTE bandwidth. Referring to FIG. 8 , it can be seen that the metric value is greatly reduced in the frequency D to frequency E band.

This can be considered that the metric value is greatly reduced because CRS symbols are actually transmitted in frequency A to frequency D bands and CRS symbols are not transmitted in frequency D to frequency E bands. Accordingly, when the electronic device 120 fails to obtain LTE bandwidth information on the neighboring base station, iteration is performed according to the increasing order of the LTE bandwidth value, and the metric value is the largest until the previous section of the bandwidth. It can be estimated that the LTE bandwidth of the neighboring base station.

9 is a block diagram of a wireless communication device according to an exemplary embodiment of the present disclosure.

Referring to FIG. 9 , the wireless communication device 1200 may include a modem (MODEM) (not shown) and a radio frequency integrated circuit (RFIC) 1260 , and the modem is an application specific integrated circuit (ASIC) 1210 . , an Application Specific Instruction Set Processor (ASIP) 1230 , a memory 1250 , a main processor 1270 , and a main memory 1290 . The wireless communication device 1200 of FIG. 9 may be the electronic device 120 according to an embodiment of the present disclosure.

The RFIC 1260 may be connected to the antenna Ant to receive a signal from the outside or transmit a signal to the outside using a wireless communication network. The RFIC 1260 may include the CRS interference cancellation circuit 465 described above with reference to FIGS. 2 to 8B . According to the technical idea of the present disclosure, the RFIC 1060 may receive individual cell information from the serving base station 110 and effectively perform interference cancellation for LTE CRS transmitted by each of the adjacent base stations. Also, the RFIC 1260 may receive common cell information, determine whether adjacent base stations actually transmit CRS symbols, and perform interference cancellation for LTE CRS.

The ASIP 1230 is an integrated circuit customized for a specific use, and may support a dedicated instruction set for a specific application, and may execute instructions included in the instruction set. The memory 1250 may communicate with the ASIP 1230 and may store a plurality of instructions executed by the ASIP 1230 as a non-transitory storage device. For example, memory 1250 may include, by way of non-limiting example, random access memory (RAM), read only memory (ROM), tape, magnetic disk, optical disk, volatile memory, non-volatile memory, and combinations thereof; It may include any type of memory accessible by ASIP 1030 .

The main processor 1270 may control the wireless communication device 1200 by executing a plurality of instructions. For example, the main processor 1270 may control the ASIC 1210 and the ASIP 1230 , and may process data received through a wireless communication network or process a user's input to the wireless communication device 1200 . may be The main memory 1290 may communicate with the main processor 1270 and may store a plurality of instructions executed by the main processor 1270 as a non-transitory storage device. For example, main memory 1290 may include, by way of non-limiting example, random access memory (RAM), read only memory (ROM), tape, magnetic disk, optical disk, volatile memory, non-volatile memory, and combinations thereof. , may include any type of memory accessible by the main processor 1270 .

Exemplary embodiments have been disclosed in the drawings and specification as described above. Although the embodiments have been described using specific terms in the present specification, these are used only for the purpose of explaining the technical spirit of the present disclosure, and are not used to limit the meaning or the scope of the present disclosure described in the claims. Therefore, it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the true technical protection scope of the present disclosure should be defined by the technical spirit of the appended claims.

Claims (10)

In the operating method of an electronic device supporting dynamic spectrum sharing (DSS),
performing a radio resource control (RRC) connection with the serving base station;
receiving information for interference cancellation from the serving base station;
receiving a cell specific reference signal (CRS) from at least one neighboring base station different from the serving base station; and
and performing interference cancellation based on the CRS and the interference cancellation information. The method according to claim 1,
The information for the interference cancellation is,
Corresponding to individual cell information including at least long term evolution (LTE) bandwidth, number of CRS ports, multimedia broadcast signal frequency network (MBSFN) configuration information, and time division duplex (TDD) configuration information for the at least one neighboring base station. Characterized method of operation. 3. The method according to claim 2,
The step of performing the interference cancellation comprises:
identifying a transmission position of a CRS symbol received from the at least one neighboring base station based on the individual cell information; and
and performing interference cancellation based on the identified transmission location. The method according to claim 1,
The information for the interference cancellation is,
First information indicating the maximum LTE bandwidth value allowed for the at least one neighboring base station, second information indicating whether to use the CRS port of the at least one neighboring base station, MBSFN configuration information of the at least one neighboring base station An operating method, characterized in that it corresponds to common cell information including at least third information indicating whether ? 5. The method according to claim 4,
The step of performing the interference cancellation comprises:
performing channel estimation for the CRS based on the common cell information; and
Method of operation characterized in that it further comprises the step of measuring the reception metric for the CRS. 6. The method of claim 5,
The reception metric corresponds to any one of reference signal received power (RSRP), signal to interference noise ratio (SINR), received signal strength index (RSSI), and received signal received quality (RSRQ). 6. The method of claim 5,
comparing the measured reception metric with a threshold value; and
When the measured reception metric exceeds the threshold, determining that the CRS symbol has been actually transmitted, and performing interference cancellation on the CRS symbol. 8. The method of claim 7,
When the measured reception metric is less than the threshold value, it is determined that the CRS symbol is not actually transmitted, and the interference cancellation for the CRS symbol is bypassed. The method according to claim 1,
The serving base station supports both 5G NR and LTE,
The at least one neighboring base station operating method, characterized in that supporting LTE. a communication unit for receiving information for interference cancellation from a serving base station simultaneously supporting 5G and LTE, and receiving a cell specific reference signal (CRS) from at least one neighboring base station supporting LTE;
a storage unit for storing predefined threshold value information; and
and a controller configured to perform radio resource control (RRC) connection with the serving base station, and control to perform interference cancellation based on the CRS and the interference cancellation information.

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