Interference cancellation circuit, method of operating interference cancellation circuit, and wireless communication device

Abstract

An interference cancellation circuit, an operation method of the interference cancellation circuit, and a wireless communication apparatus are provided. The interference cancellation circuit may include a kernel generation circuit configured to: generate an interference model based on a transmit signal; an adaptive filter configured to: estimate coefficients of an interference model based on an adaptive algorithm to generate an interference estimation signal, and filter the interference estimation signal from the received signal to generate an interference cancellation signal; and a parameter control (PC) circuit configured to generate a control signal for controlling at least one parameter of the adaptive algorithm based on transmission signal information of the transmission signal, and transmit the control signal to the adaptive filter.

Description

[0001] This application is based on and claims priority to Korean Patent Application No. 10-2024-0136819, filed on October 8, 2024, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. TECHNICAL FIELD

[0002] One or more embodiments of the present application relate to an interference cancellation circuit and an operation method of the interference cancellation circuit, and more particularly, to an interference cancellation circuit for removing intermodulation interference based on a relative delay between transmission signals, an operation method of the interference cancellation circuit, and a wireless communication apparatus. BACKGROUND

[0003] A wireless communication system can employ various techniques to increase throughput. For example, the wireless communication system can employ carrier aggregation (CA), evolved universal terrestrial radio access (E-UTRA) and new radio (NR) dual connectivity (EN-DC), multiple input and multiple output (MIMO), etc. that increase communication capacity by using multiple antennas. As techniques for increasing transmission capacity are employed, a transmitter can be able to transmit a signal with high complexity, and a receiver can need to process a signal with high complexity.

[0004] An interference signal can hinder a receiver from processing a signal received through an antenna, and the interference signal can occur in various ways. For example, the interference signal can include inter-cell interference (inter-cell interference is a signal received from a neighboring base station at a boundary of a serving base station), intra-cell interference (intra-cell interference corresponds to a wireless signal of another terminal within a coverage area of a serving base station), and channel interference.

[0005] In addition to an interference signal received through an antenna, there is an interference signal generated when a transmission signal within a terminal leaks to or is coupled onto a reception path. In the case of self-interference signals generated within a terminal, an amplified transmission signal is fed back as an interference signal, which can have a great impact on degradation of reception sensitivity. Recently, technology development is actively being conducted to remove an interference signal caused by intermodulation (IMD) between transmission signals transmitted through multiple transmission paths using an adaptive algorithm. However, when channel characteristics (e.g., resource block (RB) size, etc.) of an interference signal suddenly change, there is a problem that a convergence speed of the adaptive algorithm for removing the interference signal is reduced, thereby causing degradation of interference removal performance. SUMMARY

[0006] One or more embodiments of this application provide an interference cancellation circuit, an operation method of the interference cancellation circuit, and a wireless communication device for effectively removing interference signals when the channel characteristics of the interference signal suddenly change.

[0007] According to one aspect of this disclosure, an interference cancellation circuit is provided, the interference cancellation circuit comprising: a kernel generation circuit configured to generate an interference model based on a transmitted signal; an adaptive filter configured to estimate coefficients of the interference model based on an adaptive algorithm to generate an interference estimation signal, and to filter the interference estimation signal from a received signal to generate an interference cancellation signal; and a parameter control (PC) circuit configured to generate a control signal for controlling at least one parameter of the adaptive algorithm based on transmission signal information of the transmitted signal, and to send the control signal to the adaptive filter.

[0008] According to another aspect of this disclosure, a method for operating an interference cancellation circuit is provided, the method comprising: generating an interference model based on a transmitted signal; generating a control signal for controlling at least one parameter of an adaptive algorithm in an adaptive filter based on transmitted signal information received from a transmitted filter; generating an interference estimation signal by estimating the coefficients of the interference model based on the adaptive algorithm updated via the control signal; and filtering the interference estimation signal from a received signal.

[0009] According to another aspect of this disclosure, a wireless communication device is provided, the wireless communication device comprising: a transmit filter electrically connected to a first antenna; a receive filter electrically connected to a second antenna; and an interference cancellation circuit configured to generate an interference estimation signal based on an adaptive algorithm, filter out the interference estimation signal from a received signal, and control at least one parameter of the adaptive algorithm based on transmit signal information received from the transmit filter. Attached Figure Description

[0010] Embodiments of the inventive concept will become clearer from the following detailed description taken in conjunction with the accompanying drawings.

[0011] Figure 1 An example is shown where the channel characteristics of the interference signal change according to an embodiment.

[0012] Figure 2 This is a block diagram illustrating an example of self-interference caused by a transmitted signal according to an embodiment.

[0013] Figure 3 This is a block diagram illustrating an example of a wireless communication device according to an embodiment.

[0014] Figure 4 This is a block diagram illustrating an example of an interference cancellation circuit according to an embodiment.

[0015] Figure 5is a block diagram illustrating an example of a parameter control (PC) circuit according to an embodiment.

[0016] Figure 6 is a graph illustrating an operation of an interference cancellation circuit according to an embodiment.

[0017] Figure 7 is a block diagram illustrating another example of an interference cancellation circuit according to an embodiment.

[0018] Figure 8 is a flowchart for explaining an operation method of an interference cancellation circuit according to an embodiment.

[0019] Figure 9 is a flowchart for explaining an operation method of an interference cancellation circuit according to an embodiment.

[0020] Figure 10A is a graph illustrating an operation of an interference cancellation circuit according to a comparative embodiment.

[0021] Figure 10B is a graph illustrating an operation of an interference cancellation circuit according to an embodiment.

[0022] Figure 11A is a graph illustrating an operation of an interference cancellation circuit according to a comparative embodiment.

[0023] Figure 11B is a graph for comparing and explaining an operation of an interference cancellation circuit according to an embodiment and an operation of an interference cancellation circuit according to a comparative embodiment.

[0024] Figure 12 is a block diagram of a wireless communication apparatus according to an embodiment. DETAILED DESCRIPTION

[0025] Hereinafter, embodiments of the inventive concept will be described in detail with reference to the accompanying drawings. Although the embodiments of the inventive concept are illustrated in the drawings and described in detail, they are not intended to limit various embodiments of the inventive concept to specific forms. For example, it will be apparent to those skilled in the art that various modifications can be made to the embodiments of the inventive concept.

[0026] The interference cancellation circuit 300 according to an embodiment can be included in a wireless communication apparatus (e.g., a terminal) that performs wireless communication based on at least one transmission path (i.e., at least one antenna).

[0027] An uplink (UL) block according to an embodiment can include a transmit radio frequency (RF) chain (e.g., a transmit filter), and a downlink (DL) block can include a receive RF chain (e.g., a receive filter).

[0028] In one embodiment, at least a portion of the transmitted signal from the UL block (or transmit filter) may leak into the DL block (or receive filter) and cause interference (e.g., self-interference). In this case, from the perspective of the DL block (or receive filter), the transmitted signal from the UL block (or transmit filter) can be identified as an interference signal. Hereinafter, at least a portion of the transmitted signal may be received as an interference signal by the DL block (or receive filter).

[0029] Figure 1 An example is shown where the channel characteristics of the interference signal change according to an embodiment.

[0030] In detail, Figure 1 This diagram illustrates the time-frequency resource allocation (TX allocation) for transmitted signals, represented in units of resource blocks (RBs), and the time-frequency resource allocation (RX allocation) for received signals. Figure 1 At the receiving end of the device, it is assumed that self-interference exists due to intermodulation between transmitted signals, and the receiving end of the device uses an adaptive filter ( Figure 4 Interference cancellation circuit (330 in the middle) Figure 3 In this case, the adaptive filter 330 can filter out interference signals from the received signal based on an adaptive algorithm (e.g., recursive least squares (RLS) algorithm).

[0031] Reference Figure 1 In the time-frequency resource allocation diagram (TX allocation) used for transmitting signals, the transmit signal PUSCH (50RB) (e.g., PUSCH#1 (50RB) and PUSCH#2 (50RB)) and the transmit signal PUCCH (2RB) (e.g., PUCCH#1 (2RB) and PUCCH#2 (2RB)) can be alternately allocated to each UL slot. For example, the transmit signal PUSCH (50RB) can correspond to 14 symbols, and the transmit signal PUCCH (2RB) can correspond to 2 symbols. In the time-frequency resource allocation diagram (RX allocation) used for receiving signals, the receive signal PDCCH (e.g., PDCCH#1, PDCCH#2, PDCCH#3, and PDCCH#4) and the receive signal PDSCH (e.g., PDSCH#1, PDSCH#2, and PDSCH#3) can be alternately allocated to each DL slot.

[0032] When the transmission signal PUSCH#1 changes to the transmission signal PUCCH#1 at the UL slot boundary X, the interference signal can also change abruptly (e.g., from 50 RBs to 2 RBs) as the resource block (RB) size of the transmission signal changes. The convergence speed of the adaptive filter 330 (e.g., the coefficients of the adaptive filter 330) rapidly decreases due to the interference signal caused by the transmission signal PUCCH#1 (2 RBs), and thus, decoding of the downlink control information (DCI) of the reception signal PDCCH#2 can fail. Since the UL specification of long term evolution (LTE) and / or NR allows independent channel allocation and independent power allocation per slot and symbol, this phenomenon can occur at a high frequency.

[0033] Therefore, the interference cancellation circuit 300 according to the embodiment can adaptively control the parameters of the adaptive algorithm according to the characteristics of the transmission signal based on the transmission signal information regarding the characteristics of the transmission signal, thereby improving the convergence speed of the adaptive filter (e.g., the coefficients of the adaptive filter).

[0034] In addition, the interference cancellation circuit 300 according to the embodiment can effectively remove the interference signal at the reception end based on low system complexity by improving the convergence speed of the adaptive filter, thereby improving the overall communication performance.

[0035] In Figure 1 , for convenience of description, a case where the RB size of the transmission signal decreases is used as an example, but is not limited thereto, and the interference cancellation circuit 300 according to the embodiment can be applied to various cases where the characteristics of the transmission signal change (e.g., a case where the RB size of the transmission signal increases).

[0036] Figure 2 is a block diagram showing an example of self-interference caused by a transmission signal according to an embodiment.

[0037] Referring to Figure 2 , the electronic device 1 can include a duplexer 10 and an interference cancellation circuit 20. The electronic device 1 can correspond to a user equipment (UE). The interference cancellation circuit 20 can be implemented as a digital circuit or at least one processor.

[0038] In one embodiment, the duplexer 10 can transmit a signal through a transmission antenna and receive a signal through a reception antenna. The duplexer 10 can be connected to the transmission antenna and the reception antenna. For example, each of the transmission antenna and the reception antenna can be connected to a transmission radio frequency (RF) chain and a reception RF chain through the duplexer 10. The duplexer 10 can receive a wireless signal through the reception RF chain and transmit a baseband signal to an external device through the transmission RF chain.

[0039] In one embodiment, in a case where the electronic device 1 includes a transmit antenna and a receive antenna connected through the duplexer 10, feedback of a transmit signal based on the transmit antenna and the receive antenna adjacent to each other can occur. Also, because the duplexer 10 is connected to both the transmit RF chain and the receive RF chain, at least a part of the transmit signal from the transmit RF chain can leak into the receive RF chain. When the leaked signal is input into the receive RF chain, interference can occur. Also, when signals leak from at least two transmit RF chains into the receive RF chain, intermodulation can occur between the signals leaked through the two or more transmit RF chains, and interference due to the intermodulation (hereinafter, intermodulation interference) can also occur. The interference can be referred to as including both the self-interference and the intermodulation interference.

[0040] The interference cancellation circuit 20 can remove the interference including both the self-interference and the intermodulation interference. For example, the interference cancellation circuit 20 can include an adaptive filter that changes coefficients (e.g., coefficients of an interference model) to converge a filter to an optimal state. The interference cancellation circuit 20 can remove the interference by updating filter coefficients such that an error that is a difference between a receive signal and an interference estimation signal converges to 0. A detailed description of the interference cancellation circuit 20 is provided below.

[0041] Figure 3 is a block diagram illustrating an example of a wireless communication device according to an embodiment.

[0042] Referring to Figure 3 A first transmit signal TX1 and a second transmit signal TX2 can be transmitted. For example, the first transmit signal TX1 can be filtered to only a desired frequency band through a first transmit filter (e.g., attacker #1) 110 and converted from a digital signal to an analog signal through a first digital-to-analog converter (DAC) 111. Thereafter, a transmit frequency of the first transmit signal TX1 is up-converted to an LO frequency received from a local oscillator LO through a first mixer 112. Next, the first transmit signal TX1 can be amplified through a first power amplifier PA 113 and then transmitted to an external device (e.g., a base station) through an antenna.

[0043] The second transmit signal TX2 can be filtered to only a desired frequency band through a second transmit filter (e.g., attacker #2) 120 and converted from a digital signal to an analog signal through a second DAC 121. Thereafter, a transmit frequency of the second transmit signal TX2 is up-converted through an LO frequency received by a second mixer 122. Next, the second transmit signal TX2 can be amplified through a second power amplifier PA 123 and then transmitted to an external device through an antenna.

[0044] According to various embodiments, the electronic device 1 can perform carrier aggregation or dual connectivity, and the first transmission filter 110, the second transmission filter 120, and the reception filter (e.g., victim #2) 210 can all be in an on state. In this case, when self-interference occurs, the first transmission signal TX1 amplified through the first PA 113 can be coupled onto the adjacent reception RF chain. For example, the first transmission signal TX1 can be input as a reception signal to the low noise amplifier LNA 211 of the reception RF chain. Also, the second transmission signal TX2 can leak from the transmission RF chain connected through the duplexer 124. That is, the second transmission signal TX2 can be input as a reception signal to the low noise amplifier 211 through the duplexer 124. Due to the non-linear characteristic of the reception RF chain, the first transmission signal TX1 and the second transmission signal TX2 generate an interference signal close to the reception frequency, which is down-converted by the LO frequency received by the third mixer 212 and can be converted into a digital signal through the analog-to-digital converter ADC 213. In addition to the non-linear characteristic of the reception RF chain, interference due to intermodulation can also occur between signals leaked through two or more transmission RF chains. Thereafter, the interference signal generated by the first transmission signal TX1 and the second transmission signal TX2 can be removed through the interference cancellation circuit 300. In one embodiment, similar to the reception RF chain corresponding to the transmission RF chain including the second transmission filter 120, the reception RF chain corresponding to the transmission RF chain including the first transmission filter 110 can include a reception filter (e.g., victim #1).

[0045] The interference cancellation circuit 300 can include a kernel generation circuit 310 and an adaptive filter 330. The kernel generation circuit 310 can be a circuit that receives an interference signal (e.g., at least a portion of the first transmission signal TX1 and / or at least a portion of the second transmission signal TX2) and reproduces (or regenerates) an interference model. The interference model can represent a machine learning model, or a mathematical model representing characteristics of the interference signal, and the kernel generation circuit 310 can use a kernel to capture a pattern or correlation in data and represent an inference of interference to a signal. The adaptive filter 330 can generate an interference estimation signal by estimating coefficients of the kernel generation circuit 310 (i.e., coefficients of the interference model), and the interference cancellation circuit 300 can perform filtering (to generate an interference cancellation signal) by subtracting the interference estimation signal from a reception signal. For example, the adaptive filter 330 can perform filtering based on an RLS algorithm to calculate parameters (coefficients) of the adaptive filter 330 in real time, thereby minimizing an error between a predetermined desired output signal and an actual output of the adaptive filter 330. Figure 2 The interference cancellation circuit 20 of FIG. 1A can correspond to the interference cancellation circuit 300 of FIG. 3. Figure 3 The interference cancellation circuit 300 of FIG. 3 can correspond to the interference cancellation circuit 20 of FIG. 1A.

[0046] Figure 4is a block diagram illustrating an example of an interference cancellation circuit according to an embodiment.

[0047] Referring to Figure 4 The interference cancellation circuit 300 can include a kernel generation circuit 310, an adaptive filter 330, and a parameter control (PC) circuit 350.

[0048] In one embodiment, the kernel generation circuit 310 can receive a plurality of transmission signals and reproduce (re-generate or update) interference models. The reproduced interference models can include both active interference signals and passive interference signals. The plurality of transmission signals can be transmission signals of a plurality of RF transmission chains. The kernel generation circuit 310 can receive the plurality of transmission signals and generate a plurality of interference model signals. For example, a first kernel generation circuit can receive all transmission signals of a first transmission RF chain to an Nth transmission RF chain and generate a first interference model signal based on all transmission signals of the first transmission RF chain to the Nth transmission RF chain. An Nth kernel generation circuit can receive all transmission signals of the first transmission RF chain to the Nth transmission RF chain and generate an Nth interference model signal. In one embodiment, the kernel generation circuit 310 can retrieve a pre-stored interference model from a memory and update the pre-stored interference model based on the transmission signals.

[0049] In one embodiment, the adaptive filter 330 can generate an interference signal (e.g., an interference estimate signal) by estimating coefficients of the kernel generation circuit 310 and can perform filtering of the interference signal by subtracting the interference signal (e.g., the interference estimate signal) from a reception signal. According to an embodiment, the adaptive filter 330 can be based on at least one of an adaptive algorithm such as an RLS algorithm, a least mean square (LMS) algorithm using a stochastic gradient descent method, and a dichotomic coordinate descent (DCD)-RLS algorithm.

[0050] In one embodiment, the PC circuit 350 can receive transmission signals from at least one UL block. That is, the PC circuit 350 can receive transmission signals from at least one UL block of the transmission filter (e.g., the adaptive filter 330) and the transmission signal generator (e.g., the kernel generation circuit 310). Figure 3The first transmission filter 110 and / or the second transmission filter 120 of the at least one UL block receives transmission signal information. At least one of the parameters of the adaptive algorithm can be controlled based on the above transmission signal information. Here, the transmission signal information is symbol unit information of an uplink (UL) signal, and can include RB size information, offset variation information, bandwidth part (BWP) setting variation information (or referred to as variation information of a BWP setting), system bandwidth (BW) variation information (or referred to as variation information of a BW), and information indicating that a carrier component (CC) is activated / deactivated, but is not limited thereto. The parameters of the adaptive algorithm can include a regularization value, a variable forgetting factor, initialization of a correlation matrix (or referred to as correlation matrix initialization), and the number of taps of an adaptive filter, but are not limited thereto. Specific operations of the PC circuit 350 are described below in Figure 5

[0051] Figure 5 is a block diagram illustrating an example of a PC circuit according to an embodiment.

[0052] Referring to Figure 5 , the PC circuit 350 can include a pre-processing circuit 351, a first sub-PC circuit 352-1, a second sub-PC circuit 352-2, a third sub-PC circuit 352-3, and a fourth sub-PC circuit 352-4.

[0053] From the perspective of a DL block (or reception filter) (self-interference case), transmission signals transmitted from at least one UL block can be identified as interference signals. For example, at least a part of the transmission signals can be received as interference signals by the DL block (or reception filter). Figure 5

[0054] The pre-processing circuit 351 can receive transmission signal information from at least one UL block. For example, the pre-processing circuit 351 can receive transmission signal information from the first transmission filter (first TX filter 110) of the first UL block (UL block #1) in the first TX filter 110 of the at least one UL block, and the pre-processing circuit 351 can receive transmission signal information from the second transmission filter (second TX filter 120) of the second UL block (UL block #2) in the second TX filter 120 of the at least one UL block. Figure 3 Figure 3 ​​​The pre-processing circuit 351 can receive transmission signal information from the second TX filter 120 in the first TX / RX switch 110). The pre-processing circuit 351 can generate control information including at least one of a bandwidth variation of an interference signal (e.g., a bandwidth variation amount of the interference signal), a change point of the interference signal (e.g., a change time point of the interference signal), and a change location of the interference signal in a frequency domain (but not limited thereto) based on the received transmission signal information. In this case, at least a part of the transmission signal can be perceived as the interference signal from the perspective of the DL block (or the reception filter) (e.g., in the case of self-interference). The pre-processing circuit 351 can transmit the transmission signal information and the control information to the first, second, third, and fourth sub-PC circuits 352-1, 352-2, 352-3, and 352-4.

[0055] Each of the first, second, third, and fourth sub-PC circuits 352-1, 352-2, 352-3, and 352-4 can be a circuit for controlling a parameter of an adaptive algorithm (e.g., an RLS algorithm) in the adaptive filter 330 based on the transmission signal information and the control information. Figure 4

[0056] The first sub-PC circuit 352-1 can control a regularization value (or a normalization value) among at least one parameter of the adaptive algorithm. Equation 1 below can represent a cost function of the adaptive filter 330 based on the adaptive algorithm (e.g., the RLS algorithm). Figure 4 .

[0057] [Equation 1]

[0058] Here, e(n) can represent an error of the i-th received signal sample, ) can represent a variable forgetting factor, can represent a regularization value in the n-th received signal sample, and can represent a coefficient vector of the adaptive filter 330 (e.g., the adaptive filter based on the RLS algorithm) in the n-th received signal sample.

[0059] The regularization value is a positive real number weight of the coefficient of the adaptive filter 330, and the normalization value can prevent overfitting so that the coefficient of the adaptive filter 330 does not abruptly change. However, when the regularization value is set to a value that is too large, the cost function ​​​​The problem of slow convergence of errors (e.g., mean squared error) can occur, and this problem can be solved by the initialization control of the correlation matrix by the third sub-PC circuit 352-3, as described below. Parameter drift can be described as the phenomenon where, even in the cost function... Even without increasing the error (e.g., mean square error), the coefficients of the adaptive filter 330 increase without converging, and therefore the convergence speed of the adaptive filter 330 becomes very slow (see...). Figure 10A Specifically, parameter drift can significantly increase the cost function in finite-precision systems. Errors and slowing down the convergence speed of the adaptive filter 330 can lead to a deterioration in the overall communication performance of the device. Therefore, the first sub-PC circuit 352-1 according to the embodiment can control the regularization value based on the transmitted signal information and control information. To prevent parameter drift in the adaptive filter 330, the first sub-PC circuit 352-1 can control the regularization value in various ways. For example, when the RB value of the transmitted signal (i.e., the interference signal) is greater than or equal to a first threshold, the first sub-PC circuit 352-1 can regularize the value. The first sub-PC circuit 352-1 can set the regularization value to a first value when the RB value of the transmitted signal (i.e., the interference signal) is less than a first threshold and greater than or equal to a second threshold. The first sub-PC circuit 352-1 can set the regularization value to the second value when the RB value of the transmitted signal (i.e., the interference signal) is less than the second threshold and greater than or equal to the third threshold. Set to the third value. In another example, the first sub-PC circuit 352-1 can use a function based on at least one piece of information from the transmitted signal information (e.g., information about the RB size, offset, etc. of the transmitted signal) to control the regularization value. In another example, the first sub-PC circuit 352-1 can control the regularization value based on first additional information (additional information #1), transmitted signal information, and control information. Here, the first additional information (additional information #1) may be DL control information (e.g., signal-to-noise ratio (SNR) information) received from the DL block (e.g., the receive filter of at least one DL block).

[0060] The second sub-PC circuit 352-2 can control at least one parameter of the adaptive algorithm, namely the variable forgetting factor. In Equation 1 described above, the variable forgetting factor... It is a parameter that assigns weights to the error from the past to the present. ). For example, as the variable forgetting factor approaches 0, the proportion of current signal samples increases, which can improve the convergence speed of the adaptive filter 330 (e.g., coefficients of the adaptive filter 330) to the change of the transmission signal (i.e., the interference signal), but the estimation performance in the steady state can be deteriorated. On the other hand, as the variable forgetting factor approaches 1, the proportion of past signal samples increases, which can improve the estimation performance in the steady state, but the convergence speed of the adaptive filter 330 to the change of the transmission signal (i.e., the interference signal) can be reduced. Accordingly, the second sub-PC circuit 352-2 according to the embodiment can adaptively set the parameter of the adaptive algorithm by controlling the variable forgetting factor based on the transmission signal information and the control information when the transmission signal (i.e., the interference signal) changes. The second sub-PC circuit 352-2 can control the variable forgetting factor in various ways. For example, when the RB size of the transmission signal (i.e., the interference signal) is greater than or equal to a first threshold value, the second sub-PC circuit 352-2 can set the variable forgetting factor to a fourth value, when the RB size of the transmission signal (i.e., the interference signal) is less than the first threshold value and greater than or equal to a second threshold value, the second sub-PC circuit 352-2 can set the variable forgetting factor to a fifth value, and when the RB size of the transmission signal (i.e., the interference signal) is less than the second threshold value and greater than or equal to a third threshold value, the second sub-PC circuit 352-2 can set the variable forgetting factor to a sixth value. For another example, the second sub-PC circuit 352-2 can control the variable forgetting factor using a function based on at least one piece of information among the transmission signal information (e.g., information about the RB size, the offset, etc. of the transmission signal). For another example, when a trigger signal is received due to the change in the RB size of the transmission signal (i.e., the interference signal), the second sub-PC circuit 352-2 can set the variable forgetting factor in a predetermined time sequence based on a stored lookup table (LUT). Specifically, the second sub-PC circuit 352-2 sets the variable forgetting factor to a small value close to 0 in an early stage of filtering in order to quickly track the change of the transmission signal (i.e., the interference signal), and sets the variable forgetting factor to a large value close to 1 in a late stage of filtering in order to improve the estimation performance in the steady state, thereby improving the convergence speed of the adaptive filter 330 (e.g., coefficients of the adaptive filter 330). For another example, the second sub-PC circuit 352-2 can control the variable forgetting factor based on the second additional information (additional information #2), the transmission signal information, and the control information. Here, the second additional information (additional information #2) can be information indicating whether interference has occurred.

[0061] The third sub-PC circuit 352-3 can control initialization of a correlation matrix among at least one parameter of the adaptive algorithm. The initial value of the correlation matrix can be based on the SNR of the signal input to the filter tap, affecting the convergence speed of the adaptive filter 330 (e.g., the coefficients of the adaptive filter 330). For example, when the SNR of the signal input to the filter tap is high, the smaller the initial value of the correlation matrix is set, the faster the convergence speed of the adaptive filter 330 is. When the SNR of the signal input to the filter tap is medium, the convergence speed of the adaptive filter 330 tends to be slower and the sensitivity to the initial value of the correlation matrix tends to be lower than the case of the high SNR described above. When the SNR of the signal input to the filter tap is low, the sensitivity to the initial value of the correlation matrix is very low, and thus the larger the initial value of the correlation matrix is set, the better the communication performance of the entire apparatus can be improved.

[0062] Generally, in the converged state of the adaptive filter 330, the correlation matrix becomes much larger than the initial value. Thus, when the transmission signal (i.e., the interference signal) suddenly changes in the converged state of the adaptive filter 330, the adaptive filter 330 (or the adaptive algorithm) recognizes the correlation matrix in the previous converged state as the initial value. Since the correlation matrix in the previous converged state is much larger than the general initial value, the convergence speed of the adaptive filter 330 (e.g., the coefficients of the adaptive filter 330) to the change of the transmission signal (i.e., the interference signal) can become very slow (see Figure 10B). Also, when the RB size of the transmission signal changes, the coefficients of the adaptive filter 330 can also change as the amount of the interference signal input to the reception filter changes due to automatic gain control (AGC) operation and changes in analog gain due to AGC. Accordingly, the third sub-PC circuit 352-3 according to the embodiment can adaptively set the parameters of the adaptive algorithm by controlling the initialization of the correlation matrix based on the transmission signal information and the control information when the transmission signal (i.e., the interference signal) changes. The third sub-PC circuit 352-3 can control the initialization of the correlation matrix in various ways. For example, when the RB size of the transmission signal (i.e., the interference signal) is greater than or equal to a first threshold, the third sub-PC circuit 352-3 can set the initialization of the correlation matrix to be turned on (or off), and when the RB size of the transmission signal (i.e., the interference signal) is less than the first threshold, the initialization of the correlation matrix can be set to be turned off (or on). For another example, the third sub-PC circuit 352-3 can control the initialization of the correlation matrix using a function based on at least one piece of information among the transmission signal information (e.g., information about the RB size, the offset, etc. of the transmission signal). For another example, the third sub-PC circuit 352-3 can control the initialization of the correlation matrix based on the second additional information (additional information #2), the transmission signal information, and the control information. Here, the second additional information (additional information #2) can be information indicating whether interference has occurred.

[0063] The fourth sub-PC circuit 352-4 can control the number of taps of the adaptive filter among at least one parameter of the adaptive algorithm. Equation 2 below represents an equation that approximates the priori estimation error of the adaptive filter.

[0064] [Equation 2]

[0065] Here, denotes the noise variance, M denotes the number of taps of the adaptive filter, and n denotes the index of the signal sample. Referring to Equation 2, as the signal sample index (n) increases, the second term of Equation 2 decreases, and it can be confirmed that the priori estimation error quickly converges to the noise variance . On the other hand, as the number of taps M of the adaptive filter increases, the second term of Equation 2 increases, so that the priori estimation error can be confirmed to slowly converge to the noise variance Therefore, when a transmission signal (i.e., an interference signal) changes, the fourth sub-PC circuit 352-4 according to an embodiment can adaptively set a parameter of an adaptive algorithm by controlling the number of taps of an adaptive filter based on transmission signal information and control information. The fourth sub-PC circuit 352-4 can control the number of taps of the adaptive filter in various ways. For example, when an RB size of a transmission signal (i.e., an interference signal) is greater than or equal to a first threshold value, the fourth sub-PC circuit 352-4 can set the number of taps of the adaptive filter to 7, when the RB size of the transmission signal (i.e., the interference signal) is less than the first threshold value and greater than or equal to a second threshold value, the number of taps of the adaptive filter can be set to 8, and when the RB size of the transmission signal (i.e., the interference signal) is less than the second threshold value and greater than or equal to a third threshold value, the number of taps of the adaptive filter can be set to 9. For another example, the fourth sub-PC circuit 352-4 can control the number of taps of the adaptive filter using a function based on at least one piece of information among transmission signal information (e.g., information about an RB size, an offset, etc. of a transmission signal). Specifically, when the RB size of a transmission signal (i.e., an interference signal) is reduced, the fourth sub-PC circuit 352-4 can improve the convergence speed of the adaptive filter 330 (e.g., coefficients of the adaptive filter 330) by setting the number of taps of the adaptive filter to a small number.

[0066] In Figure 5 In the above-described embodiment, the interference cancellation circuit 300 is illustrated as including the first sub-PC circuit 352-1, the second sub-PC circuit 352-2, the third sub-PC circuit 352-3, and the fourth sub-PC circuit 352-4, but is not limited thereto, and the interference cancellation circuit 300 according to an embodiment can include various sub-PC circuits that adaptively control parameters of an adaptive algorithm according to control.

[0067] As described above, the interference cancellation circuit 300 (e.g., the PC circuit 350) according to an embodiment can effectively remove an interference signal from a reception signal by adaptively controlling a parameter of an adaptive algorithm based on transmission signal information in the case where a transmission signal (i.e., an interference signal) changes.

[0068] In addition, the interference cancellation circuit 300 (e.g., the PC circuit 350) according to an embodiment can improve the overall communication performance of a device by effectively removing an interference signal based on transmission signal information.

[0069] Figure 6 is a diagram illustrating an operation of an interference cancellation circuit according to an embodiment.

[0070] In detail, Figure 6A time-frequency resource allocation diagram of UL signals transmitted from each of a first transmit filter (first TX filter) and a second transmit filter (second TX filter) and represented in units of resource blocks (RBs), and a time-frequency resource allocation diagram of integrated UL signals from the UL signals represented in units of resource blocks (RBs) are shown. In Figure 6 In the above, it is assumed that the UL signals transmitted from the first transmit filter (first TX filter) and the second transmit filter (second TX filter) generate self-interference (e.g., second-order intermodulation distortion (IMD2) interference) in a receive filter.

[0071] Referring to Figure 6 , the RB size of the UL signals from the first transmit filter (first TX filter) can be changed from 30 RBs to 50 RBs at a UL slot boundary Al, from 50 RBs to 30 RBs at a UL slot boundary A2, and from 30 RBs to 50 RBs at a UL slot boundary A3. Also, the RB size of the UL signals from the second transmit filter (second TX filter) can be changed from 30 RBs to 50 RBs at a UL slot boundary Bl, from 50 RBs to 30 RBs at a UL slot boundary B2, and from 30 RBs to 50 RBs at a UL slot boundary B3. Accordingly, the integrated UL signals, which are a combination of the UL signals transmitted from the first transmit filter (first TX filter) and the second transmit filter (second TX filter), can be changed from 60 RBs to 80 RBs at a UL slot boundary Xl, from 80 RBs to 100 RBs at a UL slot boundary X2, from 100 RBs to 80 RBs at a UL slot boundary X3, from 80 RBs to 60 RBs at a UL slot boundary X4, from 60 RBs to 80 RBs at a UL slot boundary X5, and from 80 RBs to 100 RBs at a UL slot boundary X6. That is, Figure 6 The UL slot boundaries Xl to X6 of the integrated UL signals can be a change point of transmission signal information (e.g., the RB size of the transmission signal) of at least one UL block (e.g., the first transmit filter (first TX filter) and the second transmit filter (second TX filter)).

[0072] The interference cancellation circuit 300 according to the embodiment can adaptively control at least one of the parameters of the adaptive algorithm based on the transmission signal information of each change point (i.e., the UL slot boundaries X1 to X6) of the transmission signal (e.g., the RB size) of the first transmission filter (first TX filter) and the second transmission filter (second TX filter). The interference cancellation circuit 300 can generate a control signal for controlling at least one of the parameters with respect to each change point (i.e., the UL slot boundaries X1 to X6) of the transmission signal (e.g., the RB size) of the first transmission filter (first TX filter) and the second transmission filter (second TX filter), and transmit the generated control signal to the adaptive filter 330. Although the transmission signal information (e.g., the RB size of the transmission signal) changes, the adaptive filter 330 updates the parameters of the adaptive algorithm based on the received control signal, thereby improving the convergence speed of the adaptive filter 330 (e.g., the coefficients of the adaptive filter 330).

[0073] Figure 7 is a block diagram illustrating another example of an interference cancellation circuit according to an embodiment.

[0074] In the above description, it has been described that the first transmission filter (first TX filter) 110 and the second transmission filter (second TX filter) 120 of at least one UL block transmit the transmission signal information to the interference cancellation circuit 300, and the interference cancellation circuit 300 controls at least one of the parameters of the adaptive algorithm based on the received transmission signal information. However, because the data size of the above transmission signal information is quite large, a communication delay due to data overload can occur during the transmission processing of the transmission signal information.

[0075] Therefore, referring to Figure 7According to another embodiment, at least one of the transmit filters can use at least one sub-PC circuit to control at least one of the parameters of the adaptive algorithm (e.g., RLS algorithm). Here, the parameters of the adaptive algorithm can include a regularization value, a variable forgetting factor, initialization of a correlation matrix, and a number of taps of the adaptive filter, but are not limited thereto. For example, the first transmit filter (first TX filter) 110 can include a first sub-PC circuit 152-1, a second sub-PC circuit 152-2, a third sub-PC circuit 152-3, and a fourth sub-PC circuit 152-4. The second transmit filter (second TX filter) 120 can include a first sub-PC circuit 162-1, a second sub-PC circuit 162-2, a third sub-PC circuit 162-3, and a fourth sub-PC circuit 162-4. For example, the first transmit filter (first TX filter) 110 can generate a control signal for controlling at least one of the parameters of the adaptive algorithm based on the transmission signal information of the first transmit filter (first TX filter) (i.e., the transmission signal information of the first UL block), and transmit the generated control signal (e.g., a signal for a command for setting a regularization value, a command for setting a variable forgetting factor, a command for initializing a correlation matrix, and a command for setting a number of taps of the adaptive filter) to the adaptive filter 330. The second transmit filter (second TX filter) 120 can generate a control signal for controlling at least one of the parameters of the adaptive algorithm based on the transmission signal information of the second transmit filter (second TX filter) 120 (i.e., the transmission signal information of the second UL block), and transmit the generated control signal (e.g., a signal for a command for setting a regularization value, a command for setting a variable forgetting factor, a command for initializing a correlation matrix, and a command for setting a number of taps of the adaptive filter) to the adaptive filter 330.

[0076] As described above, according to another embodiment, the transmit filter can prevent data overload from occurring during the transmission processing of the transmission signal information by controlling the parameters of the adaptive algorithm by transmitting a control signal having a small data size to the adaptive filter 330.

[0077] Figure 8 is a flowchart for explaining an operation method of the interference cancellation circuit according to an embodiment.

[0078] Referring to Figure 8 , the method of filtering / canceling the interference signal by controlling the parameters of the adaptive algorithm by the interference cancellation circuit 300 can include operations S100 to S130. In Figure 8 , any description repeated in the description of Figures 1 to 7 is replaced with the description of Figures 1 to 7 .

[0079] From the perspective of the DL block (or receive filter) (e.g., in the case of self-interference), a transmitted signal from at least one UL block (or at least one transmit filter) can be identified as an interference signal. In the following, at least a portion of the transmitted signal can be received as an interference signal by the DL block (or receive filter).

[0080] In operation S100, the interference cancellation circuit 300 can generate an interference model based on the transmitted signal. For example, the core generation circuit 310 of the interference cancellation circuit 300 can generate (or reproduce) the interference model by receiving the transmitted signal from at least one transmitted filter.

[0081] In operation S110, the interference cancellation circuit 300 can generate a control signal based on the transmitted signal information to control at least one parameter of the parameters for controlling the adaptive algorithm in the adaptive filter 330. In one embodiment, the interference cancellation circuit 300 can receive transmitted signal information from at least one transmitted filter (i.e., at least one UL block). Here, the transmitted signal information is the symbol cell information of the UL signal and may include, but is not limited to, RB size information, offset change information, BWP setting change information, system bandwidth BW change information, and information indicating CC activation / deactivation. The preprocessing circuit 351 of the interference cancellation circuit 300 can generate control information necessary for controlling at least one parameter of the parameters for controlling the adaptive algorithm based on the transmitted signal information. The following... Figure 9 The text describes an explanation of this.

[0082] In one embodiment, at least one sub-PC circuit of the interference cancellation circuit 300 can generate a control signal for at least one parameter of the parameters for controlling the adaptive algorithm based on transmitted signal information and control information. Here, the parameters of the adaptive algorithm may include, but are not limited to, a regularization value, a variable forgetting factor, initialization of the correlation matrix, and the number of taps in the adaptive filter. In one embodiment, when the RB size of the transmitted signal (i.e., the interference signal) is greater than or equal to a first threshold, at least one sub-PC circuit can set at least one parameter to a first value; when the RB size of the transmitted signal (i.e., the interference signal) is less than the first threshold and greater than or equal to a second threshold, at least one parameter can be set to a second value; and when the RB size of the transmitted signal (i.e., the interference signal) is less than the second threshold and greater than or equal to a third threshold, at least one parameter can be set to a third value. In one embodiment, at least one sub-PC circuit can use a function based on at least one piece of information (e.g., information about the RB size, offset, etc. of the transmitted signal) to control at least one parameter.

[0083] In one embodiment, the at least one sub-PC circuit can generate a control signal for controlling a regularization value based on the transmission signal information, the control information, and first additional information. Here, the first additional information can be DL control information (e.g., SNR information).

[0084] In one embodiment, the at least one sub-PC circuit can control a variable forgetting factor based on the transmission signal information, the control information, and second additional information. Here, the second additional information can be information indicating whether interference has occurred.

[0085] In one embodiment, the at least one sub-PC circuit can control initialization of a correlation matrix based on the transmission signal information, the control information, and second additional information. Here, the second additional information can be information indicating whether interference has occurred.

[0086] In operation S120, the interference cancellation circuit 300 can generate an interference estimation signal by estimating coefficients of an interference model based on an adaptive algorithm updated according to the control signal. Here, the adaptive algorithm can include an RLS algorithm. In operation S130, the interference cancellation circuit 300 can filter (or remove) the interference estimation signal from the reception signal. For example, the adaptive filter 330 of the interference cancellation circuit 300 can update at least one of parameters of the adaptive algorithm based on the control signal, and generate the interference estimation signal based on the updated adaptive algorithm. The adaptive filter 330 can filter / remove the interference signal by subtracting the interference estimation signal from the reception signal.

[0087] Figure 9 is a flowchart for explaining an operation method of an interference cancellation circuit according to an embodiment.

[0088] Referring to Figure 9 Operation S110 in which the control signal is generated by the interference cancellation circuit 300 can include operation S111 and operation S112. In Figure 9 the description of Figures 1 to 8 is replaced with Figures 1 to 8 In the following, at least a part of the transmission signal can be received as the interference signal by the DL block (or reception filter).

[0089] In operation S111, the interference cancellation circuit 300 can generate control information including at least one of a variation of a bandwidth of the interference signal (e.g., a bandwidth variation amount of the interference signal), a change point of the interference signal (e.g., a change time point (bandwidth change time) of the interference signal), and a change location of the interference signal in a frequency domain, based on the transmission signal information (but not limited thereto). For example, the control information can include at least one of the bandwidth variation amount of the interference signal, the bandwidth change time, and the bandwidth change location (but not limited thereto). In this case, from the perspective of the DL block (or reception filter) (e.g., in the case of self-interference), the transmission signal transmitted from the at least one UL block (or at least one transmission filter) can be identified as the interference signal.

[0090] In operation S112, the interference cancellation circuit 300 can generate a control signal for controlling at least one parameter, based on the transmission signal information and the control information. For example, the control signal for controlling at least one parameter can include a signal for at least one of a command for setting a regularization value, a command for setting a variable forgetting factor, a command for initializing a correlation matrix, and a command for setting the number of taps of the adaptive filter.

[0091] Figure 10A is a graph illustrating the operation of the interference cancellation circuit according to the comparative example. Figure 10B is a graph illustrating the operation of the interference cancellation circuit according to the embodiment.

[0092] In detail, Figure 10A is a graph illustrating the convergence speed of the error of the interference cancellation circuit according to the comparative example (e.g., RLS learning curve (mean square error)), and Figure 10B is a graph illustrating the convergence speed of the error of the interference cancellation circuit according to the embodiment (e.g., RLS learning curve (mean square error)). For example, Figure 10A is a graph illustrating the convergence speed of the adaptive filter according to the comparative example (e.g., the coefficient of the adaptive filter) according to the RB size of the transmission signal, and Figure 10B is a graph illustrating the convergence speed of the adaptive filter 330 according to the embodiment (e.g., the coefficient of the adaptive filter 330) according to the RB size of the transmission signal. In Figure 10A and Figure 10B from the perspective of the DL block (or reception filter) (e.g., in the case of self-interference), the transmission signal transmitted from the UL block (or at least one transmission filter) can be identified as the interference signal. Hereinafter, at least a part of the transmission signal can be received as the interference signal by the DL block (or reception filter).

[0093] Referring to Figure 10AWhen the RB size of the transmission signal is small (e.g., when the RB size is 6), it is observed that the interference cancellation circuit in the comparative example exhibits a significant increase or unstable value of the error of the adaptive filter (e.g., the error in the cost function of the adaptive filter) due to the parameter drift phenomenon (as shown in part P of Figure 10A Thus, the convergence speed of the adaptive filter (e.g., the coefficients of the adaptive filter) in the comparative example is significantly slowed down. Specifically, because the coefficients of the adaptive filter in the comparative example do not converge quickly due to the parameter drift phenomenon (as shown in part P of Figure 10A Thus, the convergence speed of the adaptive filter (e.g., the coefficients of the adaptive filter) in the comparative example is significantly slowed down. Specifically, because the coefficients of the adaptive filter in the comparative example do not converge quickly due to the parameter drift phenomenon (as shown in part P of

[0094] Referring to Figure 10B When the RB size of the transmission signal is small (e.g., when the RB size is 6), the interference cancellation circuit 300 in the embodiment adaptively sets / controls the respective regularization values for each RB size. This adaptive control can prevent the occurrence of the parameter drift phenomenon (e.g., part P of Figure 10A Thus, the error in the adaptive filter (e.g., the error in the cost function of the adaptive filter) converges quickly from the beginning of the filtering. That is, the interference cancellation circuit 300 according to the embodiment can effectively remove the interference signal from the reception signal by improving the convergence speed of the adaptive filter (e.g., the coefficients of the adaptive filter) through the adaptive normalization control based on the control information and the transmission signal information (e.g., information about the RB size and the offset position of the transmission signal, etc.).

[0095] Thus, the interference cancellation circuit 300 according to the embodiment can effectively remove the interference signal by adaptively controlling the parameter (e.g., the normalization value) of the adaptive algorithm according to the change in the interference signal (e.g., the transmission signal).

[0096] Figure 11A is a graph showing the operation of the interference cancellation circuit according to the comparative example.

[0097] In detail, Figure 11A shows a graph (e.g., an RLS learning curve (mean square error)) showing the convergence speed of the error in the interference cancellation circuit according to the comparative example. For example, Figure 11A The graph of

[0098] Referring to Figure 11AWhen the initial value of the correlation matrix is large (for example, when the initial value (init) of the correlation matrix is 10), the error in the interference cancellation circuit according to the comparative example can be observed to converge slowly (i.e., the convergence speed of the adaptive filter (e.g., the coefficients of the adaptive filter) is significantly slowed down) (see the curve Q in Figure 11A

[0099] Figure 11B are graphs for comparing and explaining the operation of the interference cancellation circuit according to the embodiment and the operation of the interference cancellation circuit according to the comparative example.

[0100] In Figure 11B , the light-colored line graph represents the convergence speed of the error (e.g., RLS learning curve or mean square error) in the interference cancellation circuit according to the comparative example, while Figure 11B , the thick line graph represents the convergence speed of the error (e.g., DCD-RLS learning curve or mean square error) in the interference cancellation circuit 300 according to the embodiment. For example, Figure 11B , the light-colored line graph can represent the convergence speed of the adaptive filter (e.g., the coefficients of the adaptive filter) according to the comparative example without initializing the correlation matrix (R matrix). Figure 11B , the thick line graph can represent the convergence speed of the adaptive filter 330 (e.g., the coefficients of the adaptive filter 330) according to the embodiment with initializing the correlation matrix (R matrix). In Figure 11B , from the perspective of the DL block (or reception filter) (e.g., in the case of self-interference), the transmission signal transmitted from the UL block (or at least one transmission filter) can be recognized as an interference signal.

[0101] In Figure 11B , it is assumed that the RB size of the transmission signal is changed from 50 RBs to 2 RBs at the UL slot boundary C1, the RB size of the transmission signal is changed from 2 RBs to 50 RBs at the UL slot boundary C2, and the RB size of the transmission signal is changed from 50 RBs to 2 RBs at the UL slot boundary C3.

[0102] Referring to the light-colored line graph of Figure 11B , when the correlation matrix (R matrix) is not reset, it can be observed that the error of the interference cancellation circuit in the comparative example does not quickly converge as the RB size of the interference signal changes. In other words, the convergence speed of the adaptive filter (e.g., the coefficients of the adaptive filter) becomes very slow.

[0103] Referring to the thick line graph of Figure 11B ​of the coarse line graph, when the correlation matrix (R matrix) is reset (for example, when initial values of the correlation matrix (R matrix) are initialized), the error in the interference cancellation circuit 300 according to the embodiment can be observed to converge quickly. Specifically, even if the RB size of the interference signal is changed, the convergence speed of the adaptive filter 330 (for example, the coefficients of the adaptive filter 330) is very fast. In other words, the interference cancellation circuit 300 according to the embodiment can adaptively initialize the correlation matrix (R matrix) based on the control information and the transmission signal information (for example, information about the RB size and the offset position of the transmission signal).

[0104] Therefore, the interference cancellation circuit 300 according to the embodiment can effectively cancel the interference signal from the reception signal by adaptively controlling the parameters (for example, initialization of the correlation matrix) of the adaptive algorithm according to the change of the interference signal (or the interference estimation signal).

[0105] Figure 12 is a block diagram of a wireless communication device according to an embodiment.

[0106] Referring to Figure 12 The wireless communication device 1100 can include a modem and a radio frequency integrated circuit (RFIC) 1160, and the modem can include an application specific integrated circuit (ASIC) 1110, an application specific instruction set processor (ASIP) 1130, a memory 1150, a main processor 1170, and a main memory 1190. Figure 12 The wireless communication device 1100 of the coarse line graph can be an electronic device 1 according to an embodiment. The interference cancellation circuit 300 can be included in the RFIC 1160. However, it is not limited thereto, and the interference cancellation circuit 300 can be included in the modem according to the embodiment.

[0107] The wireless communication device 1100 according to the embodiment can adaptively control at least one of the parameters of the adaptive algorithm (for example, the RLS algorithm) according to the change of the interference signal (the interference estimation signal) based on the transmission signal information about the characteristics of the transmission signal received from the transmission filter. In this case, the transmission signal transmitted from at least one UL block (or at least one transmission filter) can be identified as the interference signal from the perspective of the DL block (or the reception filter). Hereinafter, at least a part of the transmission signal can be received as the interference signal by the DL block (or the reception filter). Here, the transmission signal information is the symbol unit information of the UL signal, and can include the RB size information, the offset change information, the BWP setting change information, the system bandwidth BW change information, and the information indicating that the CC is activated / deactivated, but is not limited thereto. The parameters of the adaptive algorithm can include the regularization value, the variable forgetting factor, the initialization of the correlation matrix, and the number of taps of the adaptive filter, but are not limited thereto.

[0108] For each delay signal in each transmission path, a channel impulse response (CIR) coefficient is estimated using a back propagation technique (e.g., a back propagation technique based on Wirtinger derivatives and chain rule), and the estimated CIR coefficient is reflected in an interference model to effectively remove the interference signal.

[0109] The RFIC 1160 is connected to the antenna Ant, and can receive a signal from the outside or transmit a signal to the outside using a wireless communication network. The ASIP 1130 is an integrated circuit customized for a specific purpose, and can support a dedicated instruction set for a specific application and execute instructions included in the instruction set. The memory 1150 can communicate with the ASIP 1130, and can store a plurality of instructions executed by the ASIP 1130 as a non-transitory storage device. For example, the memory 1150 can include any type of memory accessible by the ASIP 1130, such as but not limited to, a random access memory (RAM), a read only memory (ROM), a magnetic tape, a magnetic disk, an optical disk, a volatile memory, a non-volatile memory, and a combination thereof.

[0110] The main processor 1170 can control the wireless communication device 1100 by executing a plurality of instructions. For example, the main processor 1170 can control the ASIC 1110 and the ASIP 1130, process data received through a wireless communication network, or process a user input of the wireless communication device 1100.

[0111] The main memory 1190 can communicate with the main processor 1170, and can store a plurality of instructions executed by the main processor 1170 as a non-transitory storage device. For example, the main memory 1190 can include any type of memory accessible by the main processor 1170, such as but not limited to, a RAM, a ROM, a magnetic tape, a magnetic disk, an optical disk, a volatile memory, a non-volatile memory, and a combination thereof.

[0112] The foregoing exemplary embodiments are merely illustrative, and should not be construed as limiting. The present teachings can be readily applied to other types of devices. Furthermore, the description of the exemplary embodiments is intended to be illustrative, and not to limit the scope of the claims, and many alternatives, modifications, and variations will be apparent to those skilled in the art.

Claims

1. An interference cancellation circuit comprising: a kernel generation circuit configured to generate an interference model based on a transmission signal; an adaptive filter configured to estimate coefficients of the interference model based on an adaptive algorithm to generate an interference estimation signal, and to filter the interference estimation signal from a reception signal to generate an interference cancellation signal; and a parameter control circuit configured to generate a control signal for controlling at least one of parameters of the adaptive algorithm based on transmission signal information of the transmission signal, and to transmit the control signal to the adaptive filter. The parameters of the adaptive algorithm include a regularization value, a variable forgetting factor, initialization of a correlation matrix, and a number of taps of the adaptive filter.

2. The interference cancellation circuit of claim 1, wherein, The transmission signal information is symbol unit information of an uplink signal, and includes resource block size information, offset variation information, variation information of a bandwidth part setting, variation information of a system bandwidth, and information indicating whether a carrier component is activated or deactivated.

3. The interference cancellation circuit of claim 1, wherein, 4.The interference cancellation circuit of any one of claims 1 to 3, at least a part of the transmission signal received by the reception filter is an interference signal, and wherein wherein the parameter control circuit includes a preprocessing circuit configured to: generate control information including at least one of a bandwidth variation amount of the interference signal, a variation time point of the interference signal, and a variation position of the interference signal in a frequency domain, based on the transmission signal information. The parameter control circuit includes a plurality of sub-parameter control circuits, 5. The interference cancellation circuit of claim 4, wherein, wherein the preprocessing circuit is further configured to transmit the transmission signal information and the control information to the plurality of sub-parameter control circuits, and wherein each of the plurality of sub-parameter control circuits is configured to generate a control signal for controlling a parameter of the at least one parameter corresponding to the sub-parameter control circuit based on the transmission signal information and the control information. The parameter control circuit is configured to generate a control signal for controlling a regularization value of the adaptive algorithm based on the transmission signal information, the control information, and downlink control information.

6. The interference cancellation circuit of claim 4, wherein, The parameter control circuit is configured to generate a control signal for controlling a variable forgetting factor or initialization of a correlation matrix of the adaptive algorithm based on the transmission signal information, the control information, and information indicating whether an interference has occurred, the control information including at least one of a bandwidth variation amount of the transmission signal, a variation time point of the transmission signal, and a variation position of the transmission signal in a frequency domain.

7. The interference cancellation circuit of any of claims 1 to 3, wherein, The adaptive algorithm includes a recursive least square algorithm.

8. The interference cancellation circuit of any of claims 1 to 3, wherein, 9.A method of operating an interference cancellation circuit, the method comprising: generating an interference model based on a transmission signal; generating a control signal for controlling at least one of parameters of an adaptive algorithm in an adaptive filter based on transmission signal information received from a transmission filter; generating an interference estimation signal by estimating coefficients of the interference model based on the adaptive algorithm updated via the control signal; and filtering the interference estimation signal from a reception signal. The parameters of the adaptive algorithm include a regularization value, a variable forgetting factor, initialization of a correlation matrix, and a number of taps of the adaptive filter. ​ 10. The method of claim 9, wherein, ​ 11. The method of claim 9, wherein, The transmission signal information is symbol unit information of an uplink signal, and includes resource block size information, offset change information, bandwidth part setting change information, system bandwidth change information, and information indicating whether a carrier component is activated or deactivated.

12. The method of any one of claims 9 to 11, wherein, At least a part of the transmission signal received by the reception filter is an interference signal, and The step of generating the control signal for controlling the at least one of the parameters of the adaptive algorithm in the adaptive filter includes: generating control information including at least one of a bandwidth change amount of the interference signal, a change time point of the interference signal, and a change location of the interference signal in a frequency domain, based on the transmission signal information; and generating the control signal for controlling the at least one parameter based on the transmission signal information and the control information.

13. The method of claim 12, wherein, The step of generating the control signal for controlling the at least one of the parameters of the adaptive algorithm in the adaptive filter includes generating a control signal for controlling a regularization value of the adaptive algorithm, based on the transmission signal information, the control information, and the downlink control information.

14. The method of claim 12, wherein, The step of generating the control signal for controlling the at least one of the parameters of the adaptive algorithm in the adaptive filter includes generating a control signal for controlling a variable forgetting factor or initialization of a correlation matrix, based on the transmission signal information, the control information, and information indicating whether interference occurs.

15. The method of any one of claims 9 to 11, wherein, The adaptive algorithm includes a recursive least square algorithm.

16. A wireless communication apparatus comprising: a transmission filter electrically connected to a first antenna; a reception filter electrically connected to a second antenna; and an interference cancellation circuit configured to generate an interference estimation signal based on an adaptive algorithm, filter the interference estimation signal from a reception signal, and control at least one of parameters of the adaptive algorithm based on transmission signal information received from the transmission filter.

17. The wireless communication device of claim 16, wherein, The parameters of the adaptive algorithm include a regularization value, a variable forgetting factor, initialization of a correlation matrix, and a number of taps of an adaptive filter based on the adaptive algorithm.

18. The wireless communication device of claim 16, wherein, The transmission signal information is symbol unit information of an uplink signal, and includes resource block size information, offset change information, bandwidth part setting change information, system bandwidth change information, and information indicating whether a carrier component is activated or deactivated.

19. The wireless communication apparatus of any one of claims 16 to 18, wherein At least a part of the transmission signal received by the reception filter is an interference signal, and To control the at least one parameter, the interference cancellation circuit is configured to generate control information including at least one of a bandwidth of the interference signal, a change time point of the interference signal, and a change location of the interference signal in a frequency domain, based on the transmission signal information; and generate the control signal for controlling the at least one parameter based on the transmission signal information and the control information.

20. The wireless communication apparatus of any of claims 16 to 18, wherein, The adaptive algorithm includes a recursive least square algorithm.

Images