KR102157063B1 - Method and apparatus for detecting interfering signal information - Google Patents

Abstract

The present invention provides a method and apparatus for a terminal to extract interference signal information without additional signaling from a network in a communication system. According to an embodiment of the present invention, a terminal demodulates a control channel signal received from a serving cell and a neighboring cell, decodes a control channel signal received from the serving cell to extract control information, and a control channel received from the neighboring cell. The signal is decoded to extract the terminal ID, and among the terminal IDs accumulated during a predetermined subframe, only the control channel signal corresponding to the terminal ID whose cumulative number is equal to or greater than a threshold value is filtered, and the filtered control channel signal having a reliability value equal to or greater than a predetermined value Is determined as an interfering signal, and interfering signal information is extracted.

Description

Method for extracting interference signal information, and apparatus therefor {METHOD AND APPARATUS FOR DETECTING INTERFERING SIGNAL INFORMATION}

The present invention relates to a method for extracting interference signal information by a terminal without additional signaling of a network in a communication system and an apparatus therefor.

In general, in a cellular-based communication system, a terminal is interfered with by signals from another terminal using the same resource in the same cell and another terminal in an adjacent cell. In this case, if the terminal has accurate information on the interference signal, the terminal's signal is received by detecting or removing the signal to be received by the terminal itself and the interference signal using interference techniques such as joint detection. Can improve performance.

However, when only the target signal is demodulated and decoded without information on the interfering signal, there is a disadvantage in that the performance deterioration due to the interfering signal increases, and this phenomenon becomes more severe in the terminal at the cell boundary. To prevent this, control channel information for an interference signal can be obtained and used for demodulation and decoding, but in this case, information on the interference signal must be separately transmitted from the base station or blind detection must be performed. When blind detection is used, the probability of a false alarm or miss detection can be reduced with the previously proposed filtering techniques, but it is unreasonable to make an accurate judgment, which is a limiting factor in improving the interference cancellation performance.

Accordingly, the present invention proposes a method and apparatus for a terminal to directly blindly extract interference signal information from an interference control channel without additional signaling from a base station for effective processing of an interference signal of a wireless terminal.

In addition, the present invention proposes a method and apparatus for increasing accuracy by using traffic characteristics when directly decoding a control channel of an interference signal to obtain information on an interference signal.

In a communication system according to an embodiment of the present invention, a method of extracting interference signal information by a terminal includes a process in which the terminal demodulates a control channel signal received from a serving cell and a neighboring cell, and a control channel signal received from the serving cell is The process of extracting control information by decoding, and extracting a terminal ID from each candidate by blind-decoding a control channel signal candidate group received from the neighboring cell, and a terminal whose cumulative number of terminal IDs accumulated during a predetermined subframe is greater than or equal to a threshold value And filtering only the control channel signal corresponding to the ID, and extracting interference signal information by determining the filtered control channel signal having a reliability value equal to or greater than a predetermined value as an interference signal.

In addition, a method for extracting interference signal information by a terminal in a communication system according to an embodiment of the present invention is, when the terminal operates in a multi-user multiple input/output (MU-MIMO) transmission mode, among the control channel signals of the serving cell. It includes a process of extracting interference signal information from sets of control channel signals having the same DCI format as DCI (downlink control information) of the extracted control information.

In addition, an apparatus for extracting interference signal information in a communication system according to an embodiment of the present invention includes a receiver that demodulates a control channel signal received from a serving cell and a neighboring cell, and a control channel signal received from the serving cell is decoded and controlled. Information is extracted, the terminal ID is extracted by blind-decoding the control channel signal candidate group received from the neighboring cell, and only the control channel signal corresponding to the terminal ID whose cumulative number is greater than or equal to the threshold value among the terminal IDs accumulated during a predetermined subframe And a control channel decoder for filtering and extracting interference signal information by determining the filtered control channel signal having a reliability value equal to or greater than a predetermined value as an interference signal.

In addition, an apparatus for extracting interference signal information in a communication system according to an embodiment of the present invention includes a receiver for demodulating a control channel signal received from a serving cell and a neighboring cell, and a terminal in a multi-user multiple input/output (MU-MIMO) transmission mode. In the case of operating as, a control channel decoder for extracting interference signal information from a control channel signal having the same DCI format as DCI (downlink control information) of the extracted control information among control channel signals of the serving cell.

1 is a diagram showing a method in which a UE-ID is applied to a control channel in a general LTE system
FIG. 2 is a diagram illustrating a general method for a terminal to check whether the received DCI is its own information after receiving a control channel signal
3 is a diagram showing a general control channel decoding process in a terminal
4 is a schematic diagram showing a system configuration for extracting interference signal information according to an embodiment of the present invention
5 is a diagram showing the configuration of a control channel decoder according to an embodiment of the present invention
6 is a diagram showing an example in which RNTI is allocated in a general LTE communication network
7 is a diagram showing the configuration of a persistent UE-ID filtering unit 513 according to an embodiment of the present invention
8 is a diagram illustrating a method of accumulating a frequency for each UE-ID according to an embodiment of the present invention
9 is a diagram showing an example of MU-MIMO DCI format filtering according to an embodiment of the present invention
10 is a diagram showing a process of checking an interference signal according to an embodiment of the present invention

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this case, it should be noted that in the accompanying drawings, the same components are indicated by the same reference numerals as possible. In addition, detailed descriptions of known functions and configurations that may obscure the subject matter of the present invention will be omitted.

In addition, in this specification, in describing the embodiments of the present invention in detail, the wireless access network specified by the 3GPP standard, LTE (Long Term Evolution), will be the main target, but the main subject of the present invention is other It can be applied to a communication system with a slight modification within the range not significantly departing from the scope of the present invention, which will be possible by judgment of a person skilled in the technical field of the present invention.

Before describing the method of detecting an interference signal according to an embodiment of the present invention, a general method of detecting an interference signal will be described.

When the terminals are attached to the base station, the base station allocates a unique ID (hereinafter, UE-ID) to each terminal to identify the terminals. Each terminal receives only its own UE-ID through higher-level signaling, so it does not know about the UE-ID of other terminals. In the 3GPP LTE system, this UE-ID is referred to as Radio Network Temporary Identity (RNTI).

1 illustrates a method in which a UE-ID is applied to a control channel in a general LTE system.

Referring to FIG. 1, in the LTE system, after the base station generates downlink control information (DCI), a 16-bit CRC (Cyclic Redundancy Check) is attached for error-detection in the terminal. That is, the base station masks the 16-bit CRC as a UE-ID through XOR operation as a method for distinguishing the DCI of each terminal, and then transmits it through a physical downlink control channel (PDCCH).

After receiving the control channel for each subframe, the UE finds its own DCI through a blind decoding process. That is, the blind decoding process attempts to decode all radio resource units available for each terminal in the control channel, and for the decoded control channel signals, the terminal determines whether or not its DCI is recognized using its own UE-ID. It means the process of judging.

2 illustrates a general method for a terminal to check whether the received DCI is its own information after receiving a control channel signal.

Referring to FIG. 2, after decoding the received DCI, the UE generates a CRC using information bits excluding 16 bits, which is a tail bit corresponding to the CRC. If the decoded DCI belongs to the terminal itself, the terminal's own UE-ID is derived when the decoded tail bit and the CRC generated by the terminal are XORed.

Therefore, if the UE-ID derived through the XOR operation is the same as its own UE-ID (success), the decoded DCI is determined to be the terminal's own DCI, and received data is demodulated and decoded using the DCI information. However, if the UE-ID derived through the XOR operation is different from its own UE-ID (fail), it is determined that the DCI is the DCI of another terminal and the DCI is discarded.

3 shows a general control channel decoding process in a terminal.

Referring to FIG. 3, the terminal receives a control channel, performs demodulation and decoding, and then calculates a CRC using information bits of the decoded control channel (301, 303, 305). Thereafter, it is checked whether the value obtained by XORing the decoded tail bit and the calculated CRC is the same as the UE-ID of itself received from the base station (307). If the result of the verification is the same as the UE-ID, the decoded data is regarded as the terminal's own DCI, and the data channel information is demodulated and decoded using the DCI (311). On the other hand, if the result of the check at 307 is not the same as the own UE-ID, the decoded data is regarded as the DCI of another terminal and the decoded control channel data is discarded (309).

After obtaining DCI information through this process, the UE receives downlink data from the base station of the cell to which it belongs. However, when there is a terminal using the same frequency-time resource in the same cell as the corresponding terminal, or a base station of another cell is transmitting data to another terminal using the same frequency-time resource, the corresponding terminal When data is received, performance degradation occurs. Various methods have been proposed to solve the interference problem in the terminal, but performance improvement is limited when the terminal does not have accurate information about the interference signal. Therefore, in order to solve this problem, a technique for extracting UE-ID and DCI of other terminals has been proposed.

If the terminal has accurate information about the interference signal, the reception performance can be improved through a method such as joint detection between the signal to be received and the interference signal. However, as mentioned above, in general, the terminal cannot extract the DCI of another terminal with information on the interference signal because the terminal does not know the information on the UE-ID of the other terminals, and therefore, an improved algorithm such as joint detection cannot be used. . In addition, in order for the UE to know the UE-ID of the interference signal, the base station must inform the UE-ID through separate signaling or the UE must directly detect it.

However, if the base station informs the UE-ID of the interference signal, the overhead of the control channel increases. In order to solve this problem, the terminal attempts to decode all possible control channel allocations and uses a soft metric. We proposed a blind decoding method to determine the effectiveness used.

In the case of the blind decoding method for extracting the own control signal in the existing LTE system, the complexity was limited by attempting to decode only 44 by limiting the search location using the known RNTI, but the control channel decoding of other terminals When the blind decoding method used in is applied, the RNTI is not known, so decoding must be performed for all search locations and DCI formats in the entire band, and thus the RNTI false alarm frequency increases.

The complexity used for decoding the control channel of another terminal without RNTI information of the terminal is as follows. In the case of the LTE system, DCI information of each terminal is transmitted through a PDCCH composed of a plurality of control channel elements (CCEs), and the PDCCH is divided into four types of aggregation levels (ALs) according to the number of CCEs allocated to the terminal, It is divided into a number of DCI formats. Therefore, for example, when there are a total of 43 CCEs, there are 43 PDCCH candidates when AL=1, 21 when AL=2, 10 when AL=4, and 5 when AL=8. do. If there are 6 formats for the number of DCI cases, there are 474 candidates in the DCI information finally allocated to one terminal.

Therefore, in order for the UE to blindly decode all possible PDCCH candidates to obtain UE-ID and control channel information of other UEs, soft metric-based filtering or UE-ID-based filtering to lower the false alarm probability of incorrectly estimating UE-ID Method.

Soft metric-based filtering uses reliability information of decoded data. When decoding is performed on all possible DCIs, information on the decoded data is provided as a by-product of the decoder. Re-encode the decoded data to define the difference or correlation with the input data as reliability, and determine the reliability values for all possible DCIs, and PDCCH for DCIs with high reliability values among them. It is determined whether or not is valid. That is, if the wireless channel environment is good, if the DCI has valid information, a DCI value having a very large reliability value will come out through the decoding and re-encoding process. However, in the soft metric-based filtering method, even if the soft metric value is large, a false alarm may occur instead of the desired UE-ID value. In particular, a false alarm is likely to occur when the AL is low.

UE-ID based filtering is a method of using the CCE of the PDCCH determined by the UE-ID of the UE. In the case of the LTE system, the location of the CCE is determined by the UE-ID (ie, RNTI) value of the corresponding UE in the PDCCH having information of each UE. If there are 43 available CCEs and AL is 1,2,4 or 8, PDCCH starts from one of 6, 6, 2, 2 CCE positions, respectively, depending on the AL value, and DCI and RNTI You can check whether is valid information. For example, if AL=1 and CCE index = 5, the CRC is calculated using the result of decoding the PDCCH, and the UE-ID value obtained by XORing this value with the tail bit is X. If the possible CCE index is {7, 8, 9, 10, 11, 12}, the CCE index 5 of the decoded PDCCH is not included in the set of possible CCE indexes as X, so UE-ID X is considered invalid and the corresponding UE -Discard ID and DCI information. However, in the UE-ID-based filtering scheme, even after filtering, there are still several RNTI candidates, so the possibility of false alarm is high. For example, when there are 4 types of AL, 1, 2, 4, 8, 6 types of DCI formats, and 43 available CCEs, the total number of possible PDCCH candidates is 474. Here, when UE-ID-based filtering is applied, on average, 96 candidates remain, and when soft metric-based filtering is additionally performed, on average, 16 PDCCH candidates remain. In other words, even if both current technologies are used, there is a high possibility of a false alarm that incorrectly estimates the UE-ID.

Accordingly, an embodiment of the present invention proposes a method and apparatus for a terminal to extract interference signal information directly from an interference control channel without additional signaling from a base station for effective processing of an interference signal of a wireless terminal.

4 is a schematic diagram of a system configuration for extracting interference signal information according to an embodiment of the present invention.

4, the terminal 400 receives a data channel 411 and a control channel 412 transmitted from a base station 410 of a serving cell, and a data channel transmitted from a base station 420 of a neighboring cell ( 421) and a control channel 422 are also received. The data channel 421 and the control channel 422 transmitted from the base station 420 of the neighboring cell act as interference signals. The signals received from the base stations 410 and 420 are transmitted to the channel estimator 403, the control channel decoder 405, and the data channel demodulator 407 through the RF receiver 401. The channel estimator 403 estimates a radio channel and transmits it to the control channel decoder 405 and the data channel demodulator 407. The control channel decoder 405 obtains DCI by decoding each of the control channels 412 received from the base station 410 of the serving cell, and transmits the DCI to the data channel demodulator 407. The data channel demodulator 407 demodulates the data channel 411 using the channel estimation result of the channel estimator 403 and the DCI transferred from the control channel decoder 405 to obtain data.

The control channel decoder 405 decodes the control channel 412 received from the base station of the serving cell and then checks whether it is a control channel signal of the terminal itself through CRC check. When the terminal operates in a multiuser MIMO (Multiuser MIMO, MU-MIMO) mode, the control channel decoder 405 performs decoding to find a control channel of another terminal using the same resource in the same serving cell. In addition, the control channel decoder 405 also performs decoding to find a control channel of an interference signal transmitted from a base station of a neighboring cell. The control channel decoder 405 checks whether the interference signal is valid by using reliability information obtained by decoding control channels received from a base station of a serving cell or a neighboring cell.

5 shows the configuration of a control channel decoder according to an embodiment of the present invention.

5, the control channel decoder is a serving cell control channel decoding unit 405 is a first serving cell control channel decoding unit 501, CRC inspection unit 503, MU (Multi-User)-MIMO DCI format filtering unit 505, a second serving cell control channel decoding unit 507, a neighboring cell control channel decoding unit 509, an interference control channel checking unit 511, and a persistent UE-ID filtering unit 513.

The first serving cell control channel decoding unit 501 decodes the control channel received from the base station of the serving cell, and the CRC check unit 503 performs CRC on the control channel decoded by the first serving cell control channel decoder 501. Do the test. The neighboring cell control channel decoding unit 509 decodes the control channel received from the base station of the neighboring cell. The MIMO DCI format filtering unit 505, the second serving cell control channel decoding unit 507, the interference control channel checking unit 511, and the persistent UE-ID filtering unit 513 control decoded according to an embodiment of the present invention. Check whether the channel's interference signal is valid. Detailed operations of the MIMO DCI format filtering unit 505, the second serving cell control channel decoding unit 507, the interference control channel checking unit 511, and the persistent UE-ID filtering unit 513 will be described below.

In an embodiment of the present invention, two techniques of persistent UE-ID filtering and MU-MIMO DCI format filtering are proposed as a method for increasing the accuracy of validity check of an interference signal.

First, a continuous UE-ID filtering method will be described.

In general, the UE-ID is assigned when the UE accesses the base station to perform communication and is transmitted through an upper layer, and the UE-ID is maintained until communication is stopped. Therefore, when the terminal is continuously receiving data for a predetermined period of time, the UE-ID is maintained at the same value, and thus the UE-ID can be accurately estimated using this characteristic. The persistent UE-DI filtering method according to an embodiment of the present invention may be used independently or may be used together with soft metric based filtering or an existing UE-ID based filtering method.

6 shows an example in which an RNTI is allocated in an LTE communication network.

Referring to FIG. 6, if an RNTI is allocated to a terminal when there is traffic to be transmitted from the base station to the terminal, it can be confirmed that the same UE-ID is maintained until the traffic ends.

Accordingly, the persistent UE-ID filtering unit 513 of the control channel decoder 405 according to an embodiment of the present invention estimates the UE-ID of the interfering signal by using such characteristics.

7 shows the configuration of the persistent UE-ID filtering unit 513 according to an embodiment of the present invention.

Referring to FIG. 7, the persistent UE-ID filtering unit 513 includes a UE-ID calculator 701, a UE-ID frequency accumulator 703, and a UE-ID frequency comparator 705.

The UE-ID calculator 701 calculates the UE-ID by performing an XOR operation on the CRC calculated from the decoded data and the tail bit obtained from the result of decoding the control channel candidates of the serving cell and the neighboring cell.

The UE-ID frequency accumulator 703 accumulates and calculates the frequency of each UE-ID calculated for each subframe, and the UE-ID frequency comparator 705 compares the cumulative frequency for each UE-ID with a predetermined threshold. Accordingly, the UE-ID whose cumulative frequency is greater than or equal to the threshold value is determined as a valid UE-ID, and the result is transmitted to the interference control channel identification unit 511. For the accuracy of UE-ID detection, by adjusting the buffer size of the UE-ID frequency accumulator 703 and the threshold of the UE-ID frequency comparator 705 according to the system environment, the probability of false alarm or detection error (missing) is appropriately adjusted. I can.

If there is no error as a result of demodulating the control channel, the UE-ID remains if the CRC regenerated from the demodulated data is XORed with the tail bit. However, in general, an error occurs during the demodulation process, and in this case, the regenerated CRC is inconsistent with the CRC applied to the transmitted signal, and thus the UE-ID detected through the XOR operation has an meaningless random pattern. However, according to an embodiment of the present invention, if there is a terminal accessing a base station to perform communication, if the UE-ID is continuously extracted over several subframes, even if an error occurs in the decoding process, a fixed UE-ID is observed. The number of times is significantly higher compared to the random pattern shown by calculating the UE-ID only in one subframe.

8 illustrates a method of accumulating the number of frequencies for each UE-ID according to an embodiment of the present invention.

Referring to FIG. 8, the UE-ID calculator 701 calculates the UE-IDs of control channel candidates for each subframe, and the UE-ID frequency accumulator 703 determines each UE during the last several subframes as much as the buffer size. -Stores the number of frequencies by ID in the buffer. The UE-ID frequency comparator 705 compares the number of frequencies of each UE-ID with a predetermined threshold value, and determines that the UE-ID is valid if it is greater than the threshold value, and determines the UE-ID as an interference control channel checker ( 511). Then, the interference control channel checking unit 511 checks whether the corresponding control channel is valid as an interference signal by using reliability information of data decoded from the control channel having the corresponding UE-ID.

Next, a method of filtering the MU-MIMO DCI format will be described.

When the terminal operates in the MU-MIMO transmission mode, the number of decoding times can be significantly reduced by reducing candidates for the DCI format that can be used by the terminal. In the MU-MIMO transmission mode, all terminals receiving signals using the same time-frequency resource within the same serving cell operate in the same transmission mode and use the same DCI format, and signals transmitted to other terminals are transmitted to the terminal itself. Acts as an interfering signal. Therefore, if the UE already knows the DCI format used by its PDCCH and is operating in the MU-MIMO transmission mode, it can be seen that other UEs using the same resource in the same serving cell also use the same DCI format.

Table 1 shows the relationship between the size of the DCI format in the LTE communication system and the transmission mode used for MU-MIMO.

DCI format size [10MHz] DCI format Transmission mode 59 2B TM8 61 2C TM9

Therefore, when MU-MIMO DCI format filtering according to an embodiment of the present invention is applied, decoding is performed only on control channel candidates having the same DCI format as the control channel candidates having the same DCI format as the DCI format. When compared to a case of decoding using a plurality of DCI formats without taking into account, the number of cases of performing decoding can be effectively reduced. For example, if the terminal is operating in a dual-layer transmission mode, the terminal is blind decoding for a DCI format corresponding to a single-layer transmission mode or a multi-layer transmission mode. Does not have to be performed.

That is, when the terminal operates in the MU-MIMO transmission mode, the MU-MIMO DCI format filtering unit 505 of FIG. 5 uses the DCI format information of the terminal extracted from the CRC inspection unit 503 to determine its own among serving cell control channel candidates. Filters only the serving cell control channel candidates matching the DCI format of <RTI ID=0.0>(</RTI> Then, the second serving cell control channel decoding unit 507 decodes the filtered serving cell control channel candidate and transmits the result to the interference control channel check unit 511. The interference control channel check unit 511 checks whether the corresponding control channel is valid as an interference signal by using the reliability information of the filtered and decoded serving cell control channel.

9 shows an example of MU-MIMO DCI format filtering according to an embodiment of the present invention.

Referring to FIG. 9, control channels transmitted to terminals of the same serving cell have a DCI format of 47 bits, a DCI format of 57 bits, and a DCI format of 59 bits. However, if the terminal knows that the terminal's own DCI format is a 57-bit DCI format using the terminal's UE-ID, the terminal decodes all control channels when performing blind decoding to obtain interference signal information of other terminals in the same serving cell. Instead, only the control channel having the same DCI format as the terminal's own DCI format is decoded. Therefore, it is possible to effectively reduce the number of decoding times.

In addition, MU-MIMO DCI format filtering may be applied together with the above-described continuous UE-ID filtering.

5, when the terminal operates in the MU-MIMO transmission mode, filtering is performed by the MU-MIMO DCI format filtering unit 505, and the control channel candidate of the serving cell by the second serving cell control channel decoder 507 When the decoded data is transmitted to the persistent UE-ID filtering unit 513 after decoding is performed, the persistent UE-ID filtering unit 513 uses the MU-MIMO DCI format according to the same method as described in FIG. 7 above. The UE-ID for the filtered serving cell control channel candidate may be estimated, and the result may be transmitted to the interference control channel checking unit 511. Then, the interference control channel checker 511 checks whether the corresponding control channel is valid as an interference signal by using reliability information of data decoded from the control channel candidate of the serving cell having the corresponding UE-ID.

10 is a diagram illustrating a process of checking an interference signal according to an embodiment of the present invention.

Referring to FIG. 10, the UE receives and demodulates control channels of a serving cell and a neighboring cell (1001), and decodes a control channel and a serving cell control channel of a neighboring cell (1003, 1005). In addition, the UE calculates the CRC using the information bits of the decoded serving cell control channel, and if the value obtained by XORing the decoded tail bit and the calculated CRC is the same as its UE-ID received from the base station, the corresponding UE-ID And DCI format are output as control information (1007, 1009). In addition, when the terminal operates in the MU-MIMO transmission mode, only the serving cell control channel having the same DCI format is filtered using the DCI format extracted according to an embodiment of the present invention (1011), and the filtered serving cell control channel is decoded. Do (1013). In addition, UE-IDs for serving cell control channels are filtered by a continuous UE-ID filtering method according to an embodiment of the present invention (1015). Also, decoding is performed on the decoded neighboring cell control channel (1003), and UE-IDs for the neighboring cell control channels are filtered by a continuous UE-ID filtering method according to an embodiment of the present invention (1015). Thereafter, using reliability information of the data decoded from the serving cell having the filtered UE-ID and the neighboring cell control channel, it checks whether the corresponding control channel is valid as an interference signal (1017), and outputs the valid channels as interference signal information (1019). ).

In FIG. 10, a case in which both DCI format filtering and continuous UE-ID filtering according to an embodiment of the present invention are applied is described, but the two filtering methods may be applied together or may be selectively applied. However, in the case of DCI format filtering, it can be used only in the MU-MIMO transmission mode.

According to the embodiment of the present invention described above, the interference signal removal and data reception performance can be improved by increasing the accuracy when the terminal obtains control channel information for the interference signal.

In addition, when the continuous UE-ID filtering method according to an embodiment of the present invention is used, the terminal can directly extract the interference signal information without the need for the base station to inform the terminal of the interference signal information, thus saving control channel resources. have.

In addition, when the continuous UE-ID filtering method according to an embodiment of the present invention is used, even when a base station transmits data to multiple terminals simultaneously using MU-MIMO within a single cell, an accurate interference signal is obtained as in the case of inter-cell interference. By extracting the information, the interference between signals of the terminal can be efficiently processed. In addition, more accurate information can be extracted by applying the MU-MIMO DCI format filtering technique according to an embodiment of the present invention in a MU-MIMO environment.

On the other hand, the embodiments of the present invention disclosed in the specification and drawings are only provided specific examples to easily explain the technical content of the present invention and to aid understanding of the present invention, and are not intended to limit the scope of the present invention. That is, it is apparent to those of ordinary skill in the art that other modifications based on the technical idea of the present invention can be implemented.

Claims (10)

In a method for a terminal to extract interference signal information in a communication system,
A process of demodulating a control channel signal received from a serving cell and a neighboring cell by the UE, and
A process of extracting control information by decoding a control channel signal received from the serving cell,
A process of extracting a terminal ID of a neighboring cell by decoding a control channel signal received from the neighboring cell during a predetermined subframe, and accumulating the extracted terminal ID;
Filtering only a control channel signal corresponding to a terminal ID whose cumulative number is greater than or equal to a threshold value from among the accumulated terminal IDs,
And extracting interference signal information by determining the filtered control channel signal having a reliability value equal to or greater than a predetermined value as an interference signal. The method of claim 1,
The filtering process,
A process of decoding a control channel signal received from the neighboring cell to extract and distinguish information bits and tail bits; and
A process of calculating a cyclic redundancy check (CRC) from the information bit and extracting the terminal ID by performing an XOR operation on the calculated CRC and the tail bit; and
Extracting and accumulating the terminal ID during the predetermined subframe; and
Interfering signal information extraction method comprising the step of filtering only the control channel signal corresponding to the terminal ID of the accumulated number of the accumulated terminal ID is equal to or greater than a threshold value. The method of claim 1,
When the terminal operates in a multi-user multiple input/output (MU-MIMO) transmission mode,
And extracting interference signal information from sets of control channel signals having the same DCI format as a downlink control information (DCI) format of control information extracted from a control channel signal of the serving cell. The method of claim 3,
The process of extracting interference signal information from the control channel signal of the serving cell,
Filtering a control channel signal having the same DCI format as the DCI of the extracted control information among control channel signals of the serving cell; and
A process of decoding a control channel signal of the filtered serving cell,
And extracting the interference signal information by determining a control channel signal of the filtered serving cell having a reliability value equal to or greater than a predetermined value as an interference signal. The method of claim 4,
The process of decoding the filtered control channel signal of the serving cell,
A process of decoding a control channel signal received from the serving cell to extract and distinguish information bits and tail bits; and
A process of calculating a cyclic redundancy check (CRC) from the information bit and extracting the terminal ID by performing an XOR operation on the calculated CRC and the tail bit; and
Extracting and accumulating the terminal ID during the predetermined subframe; and
And filtering only a control channel signal corresponding to a terminal ID whose cumulative number is equal to or greater than a threshold among the accumulated terminal IDs. In the apparatus for extracting interference signal information in a communication system,
A receiver that demodulates a control channel signal received from a serving cell and a neighboring cell,
The control channel signal received from the serving cell is decoded to extract control information, the terminal ID is extracted by decoding the control channel signal received from the neighboring cell, and the cumulative number of terminal IDs accumulated during a predetermined subframe is critical Interfering signal information extraction apparatus comprising a control channel decoder for filtering only the control channel signal corresponding to the terminal ID of a value or more, and extracting interference signal information by determining the filtered control channel signal having a reliability value greater than or equal to a predetermined value as an interference signal. The method of claim 6,
The control channel decoder,
A neighboring cell control channel decoder that decodes the control channel signal received from the neighboring cells to extract information bits and tail bits;
Calculate CRC (Cyclic Redundancy Check) from the information bit, extract the terminal ID by XOR operation of the calculated CRC and the tail bit, extract and accumulate the terminal ID during the predetermined subframe, and the accumulated Interfering signal information extraction apparatus comprising a terminal ID filtering unit for filtering only the control channel signal corresponding to the terminal ID of the accumulated number of terminal IDs equal to or greater than a threshold value. The method of claim 6,
The control channel decoder,
When the terminal operates in a multi-user multiple input/output (MU-MIMO) transmission mode, from a control channel signal having the same DCI format as the DCI (downlink control information) format of control information extracted from the control channel signal of the serving cell Interfering signal information extraction device for extracting interference signal information. The method of claim 8,
The control channel decoder,
A DCI format filtering unit for filtering a control channel signal having the same DCI format as DCI of the extracted control information among control channel signals of the serving cell,
A serving cell control channel decoder for decoding a control channel signal of the filtered serving cell,
An interference signal information extraction apparatus comprising an interference control channel checker configured to extract the interference signal information by determining a control channel signal of the filtered serving cell having a reliability value equal to or greater than a predetermined value as an interference signal. The method of claim 9,
The serving cell control channel decoding unit extracts information bits and tail bits by decoding a control channel signal received from the serving cell,
The control channel decoder,
Calculate CRC (Cyclic Redundancy Check) from the information bit, extract the terminal ID by XOR operation of the calculated CRC and the tail bit, extract and accumulate the terminal ID during the predetermined subframe, and the accumulated Interference signal information extraction apparatus further comprising a terminal ID filtering unit for filtering only the control channel signal corresponding to the terminal ID of the accumulated number of terminal IDs equal to or greater than a threshold value.

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