Signal Distortion Pre-Correction Method, Apparatus and Non-Volatile Storage Medium

Abstract

Embodiments of the present invention relate to the field of communications, and disclose a signal distortion pre-correction method, apparatus, and non-volatile storage medium. In the present invention, mutual coupling filter parameters and a candidate set of pre-distortion coefficients are obtained by training based on feedback signals collected by a plurality of coupled dipoles, so that the forward signals of current digital channels can be processed by mutual coupling filtering according to the obtained mutual coupling filter parameters, such that the target pre-distortion coefficient selected from the candidate set of pre-distortion coefficients for the forward signal after mutual coupling filtering and the forward signal of the current digital channel to be processed is a pre-distortion coefficient considering the mutual coupling factor of the digital channels. Furthermore, the distortion pre-compensation processing performed on the forward signal of the current digital channel to be processed according to the target pre-distortion coefficient can minimize the influence on the power amplifier characteristics as much as possible, greatly improving the accuracy of signal distortion pre-correction and enabling the performance advantages of the MIMO beamforming system to be better exerted.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of communications, and in particular, to a signal distortion pre-correction method, apparatus, and non-volatile storage medium. Background Art

[0002] In modern mobile communication systems, multi-carrier transmission technology and high-order digital modulation methods result in a higher peak-to-average power ratio and a larger signal transmission bandwidth in the system. When a power amplifier (PA) operates near the saturation region, it causes severe nonlinear distortion in the PA. In this case, digital pre-distortion (DPD) technology has emerged, and due to its advantages such as low cost and obvious distortion improvement effect, it has become the preferred method for distortion pre-correction in nonlinear systems.

[0003] However, in 5G millimeter-wave communications, in order to obtain a larger system capacity, a higher spectrum utilization rate, and a higher beamforming gain, massive multiple-input multiple-output (Massive MIMO) technology and analog beamforming technology are usually adopted. When using analog beamforming technology, that is, the existing MIMO beamforming system, there is a problem that one digital channel is connected to multiple analog radio frequency channels. In this case, if distortion technology is used, a pre-distorter needs to be designed to correct the nonlinear distortion of multiple PAs simultaneously. However, in this MIMO beamforming system, since there is no circulator between the PA and the antenna element, the coupling interference between digital channels has a great impact on the characteristics of the power amplifier, thereby affecting the performance advantages of the MIMO beamforming system. Summary of the Invention

[0004] Embodiments of the present invention aim to provide a signal distortion pre-correction apparatus, device, and non-volatile storage medium, aiming to remove the coupling interference between digital channels, thereby minimizing the impact on the characteristics of the power amplifier as much as possible, and further enabling the performance advantages of the MIMO beamforming system to be exerted.

[0005] To solve the above technical problems, an embodiment of the present invention provides a signal distortion pre-correction method, including:

[0006] Performing mutual coupling filtering processing on the forward signals of current digital channels according to mutual coupling filtering parameters; wherein, the mutual coupling filtering parameters are obtained by training feedback signals collected by multiple coupling elements;

[0007] Select a target predistortion coefficient from a set of predistortion coefficient candidates based on the forward signal of the current digital channel to be processed and the forward signals of the current digital channels after the mutual coupling filtering; wherein, the set of predistortion coefficient candidates is obtained by training based on the feedback signals collected by the multiple coupled dipoles.

[0008] Perform distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the target predistortion coefficient.

[0009] An embodiment of the present invention further provides a signal distortion pre-correction device, including: a coupled signal feedback control module, a predistortion learning module, a mutual coupling filtering module, and a predistortion module. The coupled signal feedback control module is connected to the predistortion learning module, the predistortion learning module is respectively connected to the mutual coupling filtering module and the predistortion module, and the mutual coupling filtering module is connected to the predistortion module.

[0010] The coupled signal feedback control module is configured to obtain the feedback signals collected by the multiple coupled dipoles and transmit the feedback signals to the predistortion learning module.

[0011] The predistortion learning module is configured to obtain mutual coupling filtering parameters and a set of predistortion coefficient candidates by training based on the feedback signals collected by the multiple coupled dipoles, transmit the mutual coupling filtering parameters to the mutual coupling filtering module, and transmit the set of predistortion coefficient candidates to the predistortion module.

[0012] The mutual coupling filtering module is configured to perform mutual coupling filtering processing on the forward signals of the current digital channels according to the mutual coupling filtering parameters and transmit the forward signals of the current digital channels after the mutual coupling filtering to the predistortion module.

[0013] The predistortion module is configured to select a target predistortion coefficient from a set of predistortion coefficient candidates based on the forward signal of the current digital channel to be processed and the forward signals of the current digital channels after the mutual coupling filtering, and perform distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the target predistortion coefficient.

[0014] An embodiment of the present invention further provides a non-volatile storage medium for storing a computer-readable program, and the computer-readable program is used for a computer to execute the signal distortion pre-correction method described above.

[0015] Compared with the prior art, in the embodiment of the present invention, the mutual coupling filter parameters and the candidate set of predistortion coefficients are obtained by training according to the feedback signals collected by the multiplexed coupling elements. Thus, the forward signals of the current digital channels can be processed by mutual coupling filtering according to the obtained mutual coupling filter parameters, so that the target predistortion coefficient selected from the candidate set of predistortion coefficients based on the forward signal after mutual coupling filtering and the forward signal of the current digital channel to be processed is the predistortion coefficient considering the mutual coupling factor of the digital channels. Furthermore, the distortion pre-compensation processing performed on the forward signal of the current digital channel to be processed according to the target predistortion coefficient can minimize the impact on the power amplifier characteristics as much as possible, greatly improving the accuracy of signal distortion pre-correction and enabling the performance advantages of the MIMO beamforming system to be better exerted. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] One or more embodiments are illustrated by way of example in the accompanying drawings, and such illustrations do not limit the embodiments.

[0017] Figure 1 is a schematic diagram of the DPD architecture of the MIMO scenario to which the signal distortion pre-correction method in the first embodiment of the present invention is applicable;

[0018] Figure 2 is another schematic diagram of the DPD architecture of the MIMO scenario to which the signal distortion pre-correction method in the first embodiment of the present invention is applicable;

[0019] Figure 3 is a flowchart of the signal distortion pre-correction method in the first embodiment of the present invention;

[0020] Figure 4 is a basic structure diagram of the mutual coupling filter in the DPD architecture of the MIMO scenario to which the signal distortion pre-correction method in the first embodiment of the present invention is applicable;

[0021] Figure 5 is a schematic diagram of selecting the mutual coupling filter parameters of each digital channel according to the signal distortion pre-correction method in the first embodiment of the present invention;

[0022] Figure 6 is a basic structure diagram of the coupling signal feedback controller in the DPD architecture of the MIMO scenario to which the signal distortion pre-correction method in the first embodiment of the present invention is applicable;

[0023] Figure 7 is a basic structure diagram of the predistorter in the DPD architecture of the MIMO scenario to which the signal distortion pre-correction method in the first embodiment of the present invention is applicable;

[0024] Figure 8It is a flowchart for training a pre-distortion candidate set in the signal distortion pre-correction method according to the second embodiment of the present invention;

[0025] Figure 9 It is a schematic structural diagram of a signal distortion pre-correction device according to the third embodiment of the present invention. Detailed implementation manners

[0026] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those of ordinary skill in the art can understand that in the embodiments of the present invention, many technical details are provided to help readers better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can still be implemented. The following division of each embodiment is for convenience of description and should not constitute any limitation to the specific implementation manner of the present invention. The various embodiments can be combined and cross-referenced with each other on the premise of no contradiction.

[0027] The first embodiment of the present invention relates to a signal distortion pre-correction method, which performs mutual coupling filtering on the forward signals of current digital channels according to mutual coupling filtering parameters; wherein, the mutual coupling filtering parameters are obtained by training based on feedback signals collected by multiple coupling dipoles; according to the forward signal of the current digital channel to be processed and the forward signals of current digital channels after the mutual coupling filtering, a target pre-distortion coefficient is selected from a pre-distortion coefficient candidate set; wherein, the pre-distortion coefficient candidate set is obtained by training based on the feedback signals collected by the multiple coupling dipoles; the forward signal of the current digital channel to be processed is subjected to distortion pre-compensation processing according to the target pre-distortion coefficient. By training to obtain the mutual coupling filtering parameters and the pre-distortion coefficient candidate set based on the feedback signals collected by the multiple coupling dipoles, the mutual coupling filtering can be performed on the forward signals of current digital channels according to the obtained mutual coupling filtering parameters, so that the target pre-distortion coefficient selected from the pre-distortion coefficient candidate set according to the forward signal after the mutual coupling filtering and the forward signal of the current digital channel to be processed is a pre-distortion coefficient considering the mutual coupling factor of the digital channel, and further, the distortion pre-compensation processing finally performed on the forward signal of the current digital channel to be processed according to the target pre-distortion coefficient can minimize the influence on the power amplifier characteristics as much as possible, greatly improving the accuracy of signal distortion pre-correction and enabling the performance advantages of the MIMO beamforming system to be better exerted.

[0028] The implementation details of the signal distortion pre-correction method of this embodiment will be described below. The following content is only implementation details provided for convenience of understanding and is not necessary for implementing this solution.

[0029] The signal distortion pre-correction method of this embodiment is applied to the DPD architecture in the MIMO scenario (which can also be called: MIMO beamforming system). In order to ensure the implementation of the signal distortion pre-correction method of this embodiment, it is necessary to adaptively adjust the structure of the existing MIMO beamforming system. Specifically, on the premise of ensuring all components in the existing MIMO beamforming system, the corresponding number of mutual coupling filter modules, pre-distortion learners, and coupled signal anti-controllers are added according to the number of digital channels. That is, each digital channel corresponds to a mutual coupling filter module, a pre-distortion learner, and a coupled signal anti-controller.

[0030] In addition, the multiple coupled dipoles involved in the signal distortion pre-correction method of this embodiment can specifically be several antenna elements that meet the requirements in the antenna element layout. That is, the multiple coupled dipoles are located in the antenna element layout, such as inside the whole machine radome, as Figure 1 shown; or they can be separately arranged outside the antenna element layout, such as on the antenna substrate at the near-field position outside the antenna, as Figure 2 shown.

[0031] For the convenience of subsequent description of the signal distortion pre-correction method of this embodiment, this embodiment uses the Figure 1 shown DPD architecture adapted to the MIMO scenario, that is, including a pre-distortion unit ( Figure 1 the pre-distortion units 100(1) to 100(J) in Figure 1 , which are collectively referred to as pre-distortion unit 100 for convenience of description), a downlink DAC (digital-to-analog conversion, D / A converter) module ( Figure 1 the DACs 110(1) to 110(J) in Figure 1 , which are collectively referred to as downlink DAC module 110 for convenience of description), an analog beamforming module ( Figure 1 the analog beamformers 120(1) to 1(20)J in Figure 1 , which are collectively referred to as analog beamforming module 120 for convenience of description), a PA group ( Figure 1The coupled signal feedback controllers 160(1) to 160(J) (collectively referred to as the coupled signal feedback controller 160 for ease of description), the predistortion learner ( Figure 1 The predistortion learners 170(1) to 170(J) in it (collectively referred to as the predistortion learner 170 for ease of description), and the mutual coupling filter ( Figure 1 The mutual coupling filters 180(1) to 180(J) in it (collectively referred to as the mutual coupling filter 180 for ease of description), and the multi-channel coupling oscillator ( Figure 1 The feedback oscillator in it, also known as the feedback oscillator in practical applications, and collectively referred to as the multi-channel coupling oscillator for ease of description) is taken as an example of the structural schematic diagram located in the antenna element array 140.

[0032] In addition, it should be noted that in practical applications, each digital channel sent by the baseband signal source will be allocated a set of the above-listed components or functional modules from 100 to 180, and the predistortion learner 170 and the mutual coupling filter 180 corresponding to each digital channel will communicate not only with the paired digital channel but also with other digital channels.

[0033] It should be understood that the above is only a structural schematic diagram of a specific DPD architecture suitable for the MIMO scenario, and does not impose any limitations on the technical solution of the present invention. In specific implementations, those skilled in the art can make adaptive modifications according to needs, and this embodiment does not limit this.

[0034] In addition, in practical applications, in the DPD architecture suitable for the MIMO scenario, the multi-channel coupling oscillator is arranged on the antenna substrate at the near-field position outside the antenna ( Figure 2 as shown), and the same needs to include Figure 1 the various components and functional modules shown, that is, the two only have different layouts of the multi-channel coupling oscillator, and the others are roughly the same. In specific implementations, those skilled in the art can build the mechanism with the multi-channel coupling oscillator arranged on the antenna substrate at the near-field position outside the antenna according to the Figure 1 structure shown, and details will not be elaborated here.

[0035] The specific process of this embodiment is as Figure 3 shown, and specifically includes the following steps:

[0036] Step 301, perform mutual coupling filtering processing on the forward signals of the current digital channels according to the mutual coupling filter parameters.

[0037] Specifically, regarding the mutual coupling filtering processing mentioned in step 301, in practical applications, it can be implemented by the Figure 1 mutual coupling filter 180 in it. For ease of understanding, the following combinesFigure 4 Specifically describe the basic structure diagram of the mutual coupling filter shown.

[0038] First, the delay element 181 (D in the figure) in the mutual coupling filter 180 delays the forward signals of each digital channel ( Figure 4 X1(n) to X J (n) in it); then, the multiplier 182 in the mutual coupling filter 180 sequentially performs vector multiplications on the forward signals after delay processing of each digital channel and the mutual coupling filter parameters corresponding to the current digital channel ( Figure 4 h 1J (0) to h Jj (N C ) operations); finally, the adder 183 in the mutual coupling filter 180 vectorially adds the forward signals of the digital channels after vector multiplication processing, and the forward signals of each digital channel after mutual coupling filtering can be obtained ( Figure 4 f J (n) in it).

[0039] By performing mutual coupling filtering processing on the forward signals of the current digital channels according to the mutual coupling filter parameters, the mutual coupling interference between the antenna elements in the antenna array layout 140 can be approximately fitted, and then when the forward signals of the current digital channels after mutual coupling filtering processing participate in the subsequent signal distortion pre-correction processing, the final pre-distortion result can be made more accurate.

[0040] In addition, regarding the above-mentioned mutual coupling filter parameters, in this embodiment, they are specifically obtained by training the feedback signals collected by multiple coupled elements.

[0041] In addition, since in specific applications each digital channel corresponds to multiple channel beam angles, and different channel beam angles will cause different mutual coupling filter parameters for the digital channel. Therefore, in order to take into account the differences in the mutual coupling filter parameters corresponding to each digital channel in the case of different channel beam angles, a mutual coupling filter parameter set can be constructed, that is, the mutual coupling filter parameters corresponding to the combination of each digital channel number and each channel beam angle are stored in this mutual coupling filter parameter set. Thus, when obtaining the mutual coupling filter parameters of each digital channel, only need to select according to the digital channel number and channel beam angle of the current digital channels in the mutual coupling filter parameter set obtained by training the feedback signals collected by multiple coupled elements.

[0042] Correspondingly, the operation performed in the above step 301 is specifically to perform mutual coupling filtering processing on the forward signals of the current digital channels according to the selected mutual coupling filter parameters of the digital channels.

[0043] Further, in order to facilitate obtaining the mutual coupling filtering parameters corresponding to each digital channel at different channel beam angles, in this embodiment, specifically, a mutual coupling filtering parameter table indexed by the digital channel number and the channel beam angle is constructed to implement the function of the above-mentioned mutual coupling filtering parameter set.

[0044] For ease of understanding, the following is described in conjunction with Figure 5 as follows:

[0045] Specifically, assume that there are M channel beam angles corresponding to each digital channel, and there are J digital channels corresponding to the baseband signal source. First, by numbering each channel beam angle, the channel beam angle number corresponding to each channel beam angle is obtained, specifically from 1 to M, and by numbering each digital channel, the digital channel number corresponding to each digital channel is obtained, specifically from 1 to J; then, according to the number of the above-mentioned channel beam angles, the rows of the mutual coupling filtering parameter table are constructed, and according to the number of the above-mentioned digital channels, the columns of the mutual coupling filtering parameter table are constructed, and a mutual coupling filtering parameter table as shown in Figure 5 can be obtained. is the mutual coupling filtering coefficient vector obtained for the current digital channel J at the channel beam angle of M, that is, the mutual coupling filtering parameter. In implementation, the specific mutual coupling filtering coefficient can be indexed by the digital channel number and the channel beam angle. That is to say, when selecting the mutual coupling filtering parameters of each digital channel in the above-mentioned constructed mutual coupling filtering parameter table according to the digital channel numbers and channel beam angles of the current digital channels, specifically, the column where the mutual coupling filtering parameter is located is positioned according to the digital channel number, and the row where the mutual coupling filtering parameter is located is positioned according to the channel angle number, so as to determine the mutual coupling filtering parameter of the digital channel corresponding to the current digital channel number at this channel beam angle ( Figure 5 in to corresponding one).

[0046] It should be understood that the above is only one way to find the mutual coupling filtering parameters of each digital channel pair according to the digital channel numbers and channel beam angles of the current digital channels, which does not constitute any limitation to the technical solution of the present invention. Those skilled in the art can set according to needs in actual applications, and no limitation is made here.

[0047] In addition, regarding the feedback signals collected by the above-mentioned multi-channel coupling dipoles, for ease of understanding, the following is still described in conjunction with Figure 1 the structure shown in

[0048] Taking the processing of one digital channel as an example, as shown in Figure 1 , each coupling dipole set in the antenna element arrangement 140(1) transmits the feedback RF signal to the corresponding analog-to-digital conversion module ADC, as shown in Figure 1In ADCs 150(1), 151(1), 152(1), and 153(1), the radio frequency signals fed back by the corresponding coupled dipoles are converted from analog to digital through the ADCs to obtain the equivalent baseband feedback signals in the digital domain, and the obtained equivalent baseband feedback signals are transmitted to the coupled signal feedback controller 160(1). The coupled signal feedback controller 160(1) processes the above equivalent baseband feedback signals to further obtain the feedback signals collected by the multiple coupled dipoles in this embodiment.

[0049] Regarding the processing of the above equivalent baseband feedback signals by the coupled signal feedback controller 160(1), the following is combined with Figure 6 for illustration:

[0050] For ease of understanding, the internal structure of the coupled signal feedback controller 160(1) is briefly described below.

[0051] Specifically, the inside of the coupled signal feedback controller 160(1) mainly includes multiple data preprocessing modules 161 (such as Figure 6 the data preprocessing module 161(1) to the data preprocessing module 161(K) in Figure 6 ), multiple data alignment modules 162 (such as Figure 6 the data alignment module 162(1) to the data alignment module 162(K) in

[0052] ), multiple data availability screening modules 163 (such as Figure 6 the data availability screening module 163(1) to the data availability screening module 163(K) in

[0053] ), and a routing module 164.

[0054] First, the data preprocessing module 161 corresponding to each equivalent baseband feedback signal performs processing operations such as mirror calibration, frequency point slicing, and feedback equalization on the input equivalent baseband feedback signal, and transmits the processed equivalent baseband feedback signal to the corresponding data alignment module 162; then, each data alignment module 162 performs alignment processing on the corresponding equivalent baseband feedback signal and the forward signal, mainly including processing operations such as delay alignment and amplitude-phase alignment, and transmits the processed equivalent baseband feedback signal to the corresponding data availability screening module 163; next, each data availability screening module 163 checks the corresponding equivalent baseband feedback signal to exclude abnormal data, and transmits the processed equivalent baseband feedback signal to the routing module 164; finally, the routing module 164 performs data splicing on the processed equivalent baseband feedback signals of each path, specifically, performs end-to-end splicing in the time domain, and then obtains the feedback signal collected by the multiple coupled dipoles in this embodiment, that is Figure 6 y in fb :[y1, y2,..., y k .[[ID=k]]

[0055] In addition, it is worth mentioning that regarding the above-mentioned inspection performed in each data availability screening module 163, the operation performed when abnormal data is detected is specifically that the corresponding data availability screening module 163 sets the signals of all links of this path to 0.

[0056] It should be understood that the above is only a specific way to obtain the feedback signal collected by the multiple coupled dipoles, and it does not constitute any limitation to the technical solution of the present invention. Those skilled in the art can set it according to needs in actual applications, and no limitation is made here.

[0057] Step 302: Select a target pre-distortion coefficient from the pre-distortion coefficient candidate set according to the forward signal of the current digital channel to be processed and the forward signals of the current digital channels after the mutual coupling filtering.

[0058] Specifically, in order to facilitate obtaining the target pre-distortion coefficient, the above-mentioned pre-distortion coefficient candidate set specifically includes a two-dimensional look-up table (2D-LUT), and the two-dimensional look-up table is used to store the corresponding relationship between the combination of the modulus value of the forward signal and the modulus values of the forward signals of the digital channels after the mutual coupling filtering and the pre-distortion coefficient.

[0059] Correspondingly, the operation of selecting the target pre-distortion coefficient from the pre-distortion coefficient candidate set mentioned in step 302 is specifically:

[0060] According to the modulus value of the forward signal of the current digital channel to be processed and the modulus values of the forward signals of the current digital channels after the mutual coupling filtering, look up the 2D-LUT table, and then obtain the corresponding pre-distortion coefficient. Finally, use the found pre-distortion coefficient as the target pre-distortion coefficient.

[0061] Furthermore, in practical applications, there are different pre-distortion systems under different signal delay conditions. Therefore, in order to make the final distortion pre-compensation processing as accurate as possible. The pre-distortion coefficient candidate set includes multiple 2D-LUTs corresponding to different signal delays.

[0062] Correspondingly, the operation of looking up the 2D-LUT mentioned above is specifically as follows: According to the modulus value of the forward signal of the current digital channel to be processed and the modulus values of the forward signals of the current digital channels after the mutual coupling filtering, look up each 2D-LUT respectively, and then obtain the corresponding pre-distortion coefficients in each 2D-LUT. Finally, use the corresponding pre-distortion coefficients in the found 2D-LUTs as the target pre-distortion coefficients respectively, that is, there are multiple finally determined target pre-distortion coefficients.

[0063] Step 303, perform distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the target pre-distortion coefficient.

[0064] Specifically, as can be seen from the description in step 302, there are multiple found target pre-distortion coefficients, that is, the corresponding pre-distortion coefficients in each 2D-LUT found according to the above lookup method are all target pre-distortion coefficients. Therefore, the distortion pre-compensation processing performed in step 303 is essentially to perform distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the multiple found pre-distortion coefficients.

[0065] To facilitate the understanding of the operations in the above step 302 and step 303, the following is combined with Figure 7 for specific description.

[0066] Specifically, Figure 7 is Figure 1 the basic structure diagram of the pre-distorter 100 in the shown structure.

[0067] As Figure 7 shown, the pre-distorter 100 mainly includes a modulus obtaining module 101, a 2D-LUT module 102 (for storing multiple 2D-LUTs corresponding to different signal delays), a delay unit 103, a multiplier 104, and an adder 105.

[0068] Among them, the numbers of the delay unit 103 and the multiplier 104 are determined according to the number of two-dimensional look-up tables stored in the 2D-LUT module 102, that is, each two-dimensional look-up table needs to correspond to one delay unit 103 and one multiplier 104.

[0069] For ease of explanation, Figure 7 taking the number of 2D-LUTs stored in the 2D-LUT module 102 as N as an example for illustration.

[0070] When selecting the target predistortion coefficient for the predistorter 100 based on the Figure 7 shown structure, specifically, the forward signal X j (n) of the current digital channel to be processed is input to the modulus calculation module 101 Figure 7 corresponding to X j (n) in it), and then the modulus |X j (n)| of the forward signal of the current digital channel to be processed is obtained. Then, the obtained |X j (n)| is respectively delayed through N delay units Figure 7 Z -m0 to Z -mN in it) to obtain N delayed |X j (n)|; the forward signal f j (n) of each current digital channel after the mutual coupling filtering is input to the modulus calculation module 101 Figure 7 corresponding to f j (n) in it), and then the modulus |f j (n)| of the forward signal of each current digital channel after the mutual coupling filtering is obtained. Then, the obtained |f j (n)| is respectively delayed through N delay units Figure 7 in it to to obtain the modulus of the forward signal after N delays, and each modulus is corresponding to a two-dimensional look-up table, and then the corresponding predistortion coefficient is found from each two-dimensional look-up table.

[0071] It should be noted that the above Z is a delay unit. Since the forward signal needs to be multiplied by the predistortion coefficients found from each 2D-LUT respectively and the results of each multiplication are added to obtain the pre-corrected forward signal, there will be N forward signals after signal delay, which are respectively multiplied by the N found predistortion coefficients; m represents the delay unit for delaying the modulus of the forward signal, d represents the delay unit for delaying the forward signal f j (n) of each current digital channel after the mutual coupling filtering, and k represents the delay unit for delaying the forward signal.

[0072] Accordingly, when performing distortion pre-compensation processing on the predistorter 100 based on the structure shown in Figure 7 , specifically, the corresponding predistortion coefficients in each found 2D-LUT are respectively vector multiplied with the forward signal X j (n) of the current digital channel to be processed, and the adder 105 adds the results of each multiplication to obtain the pre-corrected forward signal, that is, Figure 7 Y j (n) in

[0073] In addition, for the purpose of facilitating the understanding of the above-mentioned two-dimensional look-up table, this embodiment specifically describes it with the two-dimensional look-up table shown in Figure 7 . In any two-dimensional look-up table LUT j [m,n], j represents the digital channel number, and the values of m and n are [0, 1,... L-1]. Where L is the length of the two-dimensional look-up table, or the length of this matrix of the two-dimensional look-up table.

[0074] In addition, referring to the structural schematic diagram of the DPD architecture adapted to the MIMO scenario shown in Figure 1 , it can be seen that in practical applications, this architecture further includes a downlink DAC module 110, an analog beamforming module 120, a PA group 130, and an antenna element array 140. Therefore, after performing the above step 303, the following processing can also be included:

[0075] First, perform digital-to-analog conversion on the forward signal after the distortion pre-compensation processing to obtain an analog signal;

[0076] Then, perform analog beamforming processing on the analog signal;

[0077] Next, perform power amplification processing on the output signal after the analog beamforming processing to generate a radio frequency signal meeting the power requirements;

[0078] Finally, transmit the radio frequency signal through the antenna element array.

[0079] Looking at it in combination with Figure 1 , in essence, the downlink DAC module performs digital-to-analog conversion on the forward signal after the distortion pre-compensation processing by the predistorter 100, and then transmits the obtained analog signal to the analog beamforming module 120; next, the analog beamforming module 120 performs analog beamforming processing on the analog signal and transmits the processed output signal to the PA group 130; then, the PA group 130 performs power amplification processing on the output signal after the analog beamforming processing to generate a radio frequency signal meeting the power requirements; finally, the obtained radio frequency signal is transmitted through the antenna element array 140.

[0080] Accordingly, this embodiment provides a signal distortion pre-correction method. By training to obtain mutual coupling filter parameters and a candidate set of pre-distortion coefficients based on the feedback signals collected by multiple coupled antennas, the forward signals of current digital channels can be processed by mutual coupling filtering according to the obtained mutual coupling filter parameters, so that the target pre-distortion coefficient selected from the candidate set of pre-distortion coefficients for the forward signal after mutual coupling filtering and the forward signal of the current digital channel to be processed takes into account the mutual coupling factor of the digital channels. Furthermore, the distortion pre-compensation processing performed on the forward signal of the current digital channel to be processed according to the target pre-distortion coefficient can minimize the impact on the power amplifier characteristics as much as possible, greatly improving the accuracy of signal distortion pre-correction and enabling the performance advantages of the MIMO beamforming system to be better exerted.

[0081] In addition, it is not difficult to find from the above description that based on the signal distortion pre-correction method provided in this embodiment, the accuracy problem of pre-distortion compensation processing in the application scenario where one pre-distorter corresponds to multiple PAs in the DPD architecture adapted to the MIMO scenario can be effectively solved. Moreover, since the multiple coupled antennas providing feedback signals in this embodiment do not need to be remotely arranged, the complexity of the architecture is greatly reduced, while reducing the implementation cost, it also greatly facilitates the later installation and maintenance, thereby effectively improving the product competitiveness.

[0082] Reference Figure 8 , Figure 8 is the flowchart of training the candidate set of pre-distortion coefficients in the signal distortion pre-correction method of the second embodiment of the present invention.

[0083] Based on the above first embodiment, in this embodiment, the operation of training the candidate set of pre-distortion coefficients according to the feedback signals collected by the multiple coupled antennas will be specifically described. For ease of understanding, the following will be specifically described in conjunction with Figure 8 as follows:

[0084] Step 801: According to the distortion characteristics of the power amplifier output signals of the digital channels, use the forward signals of the digital channels and the feedback signals collected by the multiple coupled antennas to construct the signal matrix W j of the digital channels and the feedback signal matrix V j .

[0085] Specifically, in this embodiment, the above-mentioned signal matrix W j and the feedback signal matrix V j where j represents the channel number of the digital channel.

[0086] In addition, it should be noted that when considering the distortion characteristics of the power amplifier output signals corresponding to each digital channel and the influence of mutual coupling interference in the antenna array element layout, the relationship expression between the forward signal x j and the feedback signal y′ j (collected by multiple coupled dipoles) can be approximately expressed as formula (1):

[0087] y′ j = f(x j , h 1j *x1, h<( 2j *x2, …, h ij *x i , …, h Jj *x J ), j = 1, 2,... J (1)

[0088] In the formula, f(·) is a non-linear function describing the distortion characteristics of the power amplifier output signal; * is a linear convolution operator; h ij is the mutual coupling filter parameter vector of the i-th digital channel to the j-th digital channel; x i is the forward signal of the i-th digital channel; h ij *x i represents the crosstalk influence component of the i-th digital channel on the j-th digital channel.

[0089] Therefore, when constructing the above two matrices, it is necessary to first model the power amplifier model coefficients of the analog channels corresponding to each digital channel to reflect the distortion characteristics of the power amplifier output signals of the digital channels. The specific operations are as follows:

[0090] First, according to a specific power amplifier model (such as a memory cross-polynomial model), select the forward signal x j and the feedback signal y′ j after linear processing. The least square algorithm (LS) can be used to cross-estimate the power amplifier model coefficients and the mutual coupling filter parameters until the mutual coupling filter parameter h j and the power amplifier model coefficient c PA that meet the accuracy requirements are obtained.

[0091] Then, select the forward signals and feedback signals after linear processing of other digital channels to perform the same operations as above to obtain the mutual coupling filter parameters of each digital channel as the final estimated values of the mutual coupling filter parameters, and upload them to the mutual coupling filters 180 of each digital channel.

[0092] In addition, in this embodiment, in order to eliminate the non-linear distortion of the far-field beam center signal, the measure taken in this embodiment is to introduce a general pre-distorter 100 into each digital channel. Therefore, in order to obtain the mutual coupling filtering parameters and the forward signals of each digital channel after mutual coupling filtering, it is necessary to first model in the pre-distortion learning device 170 to obtain the power amplifier model coefficients corresponding to the power amplifier output signals of each digital channel.

[0093] To facilitate the understanding of the operations in step 801 above, in this embodiment, taking the power amplifier model as the memory cross polynomial model as an example, the above-mentioned signal matrices W j and the feedback signal matrix V j are constructed.

[0094] Specifically, when the power amplifier model is the memory cross polynomial model, the construction of the signal matrix W j and the feedback signal matrix V j can be constructed based on formulas (2) to (5) as follows:

[0095]

[0096]

[0097]

[0098]

[0099] In the above formulas (2) to (5), l (l = 0,..., L), m (m = 0,..., M), and k (k = 0,..., K) are respectively the memory depth of the polynomial model, the non-linear order of the signal modulus value, and the non-linear order of the signal after mutual coupling filtering; is an intermediate quantity for matrix construction; n is the current time; N is the number of sampling points participating in the operation; x j (n - l) is the forward signal of the j-th channel at time n - l; x j (n - l + 1) is the forward signal of the j-th channel at time n - l + 1; x j (n - l + N) is the forward signal of the j-th channel at time n - l + N; |x j (n - l)| 0 is the modulus value of the forward signal of the j-th channel at time n - l; |x j (n - l + 1)| 0 is the modulus value of the forward signal of the j-th channel at time n - l + 1; |x j (n - l + N)| 0 is the modulus value of the forward signal of the j-th channel at time n - l + N.

[0100] Correspondingly, is the forward signal at the (n - l)th moment of the jth channel after mutual coupling filtering; is the forward signal at the (n - l + 1)th moment of the jth channel after mutual coupling filtering; is the forward signal at the (n - l + N)th moment of the jth channel after mutual coupling filtering; N + 1 is the data length used to construct the matrix, which is formed by splicing the feedback signals of multiple coupled dipoles; Z is the number of analog channels corresponding to each digital channel, that is, the number of power amplifier output signals, β is the analog beamforming phase modulation amount, and θ is the phase difference from each transmitting dipole to the coupling dipole; is the forward signal corresponding to each digital channel after mutual coupling filtering.

[0101] Therefore, the feedback signal collected by the multiple coupled dipoles corresponding to the digital channel j can be expressed as the following formula:

[0102] V j = W j ·c PA (6)

[0103] In the formula, c PA represents the power amplifier model coefficient. It should be noted here that the information contained in c PA not only includes the PA characteristics of each analog channel

[0104] but also contains the influence information of the coupling characteristics between each analog channel.

[0105] Furthermore, the above-mentioned power amplifier model coefficient c PA can be obtained by fitting with the LS algorithm, and the specific formula used is as follows:

[0106] c PA = (W j H W j ) -1 W j H W j (7)

[0107] In the formula, the superscript H represents the conjugate transpose of the matrix.

[0108] Step 802, according to the W j and the V j , obtain the mutual coupling filtering parameters of the digital channel and the power amplifier model coefficient c PA .

[0109] Specifically, the power amplifier model coefficient c PA can be obtained based on the above formula (7). However, since h ij(i = 0, 1, ..., J) The parameter is unknown, and the mutual coupling filtering parameter of the digital channel needs to use the nonlinear distortion expression of the feedback signal (Equation (6)) V j = W j ·c PA , establish an error objective function; then, use the parameter solution method to extract the mismatch and mutual coupling parameters, and perform multiple iterations to obtain the mutual coupling filtering parameter h ij .

[0110] In this embodiment, regarding the above-mentioned parameter solution iterative algorithm, it includes but is not limited to the following methods:

[0111]

[0112] c(n) = μ(n)·x(n)·e H (n) (9)

[0113]

[0114] In the formula, μ and λ are the adjustment factors of the iterative algorithm; c(n) is the power amplifier model coefficient c of the nth iteration PA ; x(n) is the input signal of the distortion pre-correction model; e H is the conjugate transpose operation of the complex vector; e(n) is the fitting error value at the current moment obtained by the pre-correction model; h(n) is the weighting coefficient of the error signal e(n).

[0115] Step 803, according to the mutual coupling filtering parameter of the digital channel and the power amplifier model coefficient c PA , reconstruct the far-field beam center signal.

[0116] Regarding the operation of reconstructing the far-field beam center signal, it can be specifically implemented with reference to Equation (11):

[0117] V c = W c ·c PA (11)

[0118] Among them, V c represents the far-field beam center signal, and W c represents the signal matrix related to the beam center angle, which can be specifically the de-beamforming matrix in practical applications.

[0119] Regarding the construction of the de-beamforming matrix W c , it can be specifically implemented with reference to Equation (12):

[0120]

[0121] Among them, θ dis the beam center pointing angle, and in practical applications, it can be considered that θ d +β = 0.

[0122] It is not difficult to see that the parameters required to construct the beamforming matrix W for beam cancellation based on formula (12) c are similar to the parameters required to construct the signal matrix W of the digital channel based on formula (4) above. The main beam cancellation is that θ in formula (4) is the phase difference from each transmitting element to the coupling element, while in formula (12), it is specifically the beam center pointing angle. For the description of other parameters, please refer to the above description and will not be elaborated here. j For the description of other parameters, please refer to the above description and will not be elaborated here.

[0123] Step 804: Train to obtain the candidate set of the predistortion coefficients according to the forward signal of the digital channel, the reconstructed far-field beam center signal, and the preset training model.

[0124] It should be understood that the above-mentioned training model is the predistortion model. From the above description, it can be seen that based on the power amplifier model coefficients c of each path obtained by the above method PA , the digital channel mutual coupling filtering parameters, the far-field signal in the beam center direction of the current moment of this digital channel configuration can be reconstructed Therefore, with the help of the forward signal x j (n) and the reconstructed far-field signal and by means of the memory polynomial model, the predistortion model expression (i.e., the above-mentioned training model) can be constructed according to formula (13):

[0125]

[0126] In the formula, the coefficient c km is the DPD parameter to be solved, and its calculation can be realized by means of the LS algorithm or the LMS algorithm. Since the forward signal modulus |x j (n)| and the order of the signal f j (n) after mutual coupling filtering are configurable, the 2D-LUT (i.e., two-dimensional look-up table) indexing method with |x j (n)| and f j (n) as the index quantities is adopted in the embodiment for predistortion processing. Through the above method, the predistortion coefficients to be recorded in each 2D-LUT table can be obtained.

[0127] Accordingly, this embodiment provides a method for pre - correcting signal distortion. During the process of training the candidate set of predistortion coefficients, the far - field beam center signal is reconstructed based on the mutual - coupling filtering parameters of the digital channel and the power amplifier model coefficients, and the forward signal of the digital channel and the reconstructed far - field beam center information are extracted as required and used as the parameters for inputting into the predistortion model (training model). Thus, without setting a coupling circuit for each coupled dipole, relatively complete feedback information can be obtained, making the predistortion correction of the signal more accurate, greatly reducing the implementation difficulty, and also reducing the implementation cost as much as possible while reducing the maintenance difficulty.

[0128] In addition, those skilled in the art can understand that the step division of the above various methods is only for clear description. During implementation, they can be combined into one step or some steps can be split into multiple steps. As long as the same logical relationship is included, it is within the protection scope of this patent; adding insignificant modifications to the algorithm or process or introducing insignificant designs, but not changing the core design of its algorithm and process, are all within the protection scope of this patent.

[0129] The third embodiment of the present invention relates to a signal distortion pre - correction device, as Figure 9 shown.

[0130] The signal distortion pre - correction device includes: a coupled - signal feedback control module 901, a predistortion learning module 902, a mutual - coupling filtering module 903, and a predistortion module 904.

[0131] Among them, the coupled - signal feedback control module 901 is connected to the predistortion learning module 902. The predistortion learning module 902 is respectively connected to the mutual - coupling filtering module 903 and the predistortion module 904. The mutual - coupling filtering module 903 is connected to the predistortion module 904.

[0132] Specifically, the coupled - signal feedback control module 901 is used to obtain the feedback signals collected by multiple coupled dipoles and transmit the feedback signals to the predistortion learning module 902. Among them, the multiple coupled dipoles are arranged inside the whole - machine radome or on the antenna substrate at the near - field position outside the antenna;

[0133] The predistortion learning module 902 is used to train the mutual - coupling filtering parameters and the candidate set of predistortion coefficients according to the feedback signals collected by the multiple coupled dipoles, and transmit the mutual - coupling filtering parameters to the mutual - coupling filtering module 903 and transmit the candidate set of predistortion coefficients to the predistortion module 904;

[0134] The mutual coupling filtering module 903 is configured to perform mutual coupling filtering processing on the forward signals of the current digital channels according to the mutual coupling filtering parameters, and transmit the forward signals of the current digital channels after the mutual coupling filtering to the predistortion module 904;

[0135] The predistortion module 904 is configured to select a target predistortion coefficient from a set of candidate predistortion coefficients according to the forward signal of the current digital channel to be processed and the forward signals of the current digital channels after the mutual coupling filtering, and perform distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the target predistortion coefficient.

[0136] Based on the description of the above method embodiments, and Figure 1 from the structural schematic diagram of the DPD architecture adapted to the MIMO scenario shown, it can be seen that the above-mentioned coupling signal feedback control module 901 can specifically be, for example, Figure 1 the coupling signal feedback controller 160 shown, the predistortion learning module 902 can specifically be, for example, Figure 1 the predistortion learner 170 shown, the mutual coupling filtering module 903 can specifically be, for example, Figure 1 the mutual coupling filter 180 shown, and the predistortion module 904 can specifically be, for example, Figure 1 the predistorter 100 shown.

[0137] In addition, it is worth mentioning that in practical applications, the above functional modules can be implemented by selecting specific components such as the above-mentioned coupling signal feedback controller, predistortion learner, mutual coupling filter, and predistorter, or can be implemented by compiling corresponding software programs based on the working principles of these components. This embodiment does not limit this.

[0138] In addition, in another example, the set of candidate predistortion coefficients includes a two-dimensional look-up table, and the two-dimensional look-up table is used to store the correspondence between the combination of the forward signal modulus and the modulus of the forward signals of the digital channels after mutual coupling filtering and the predistortion coefficient.

[0139] Correspondingly, the predistortion module 904 is specifically configured to look up the two-dimensional look-up table according to the modulus of the forward signal of the current digital channel to be processed and the modulus of the forward signals of the current digital channels after the mutual coupling filtering, obtain the corresponding predistortion coefficient as the target predistortion coefficient, and perform distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the target predistortion coefficient.

[0140] In addition, in another example, the set of candidate predistortion coefficients includes multiple two-dimensional look-up tables corresponding to different signal delays.

[0141] Accordingly, the predistortion module 904 is further configured to respectively look up each two-dimensional look-up table according to the modulus value of the forward signal of the current digital channel to be processed and the modulus values of the forward signals of the current digital channels after mutual coupling filtering, to obtain the corresponding predistortion coefficients in each two-dimensional look-up table, and use them as the target predistortion coefficients respectively; and multiply the corresponding predistortion coefficients in each two-dimensional look-up table found respectively by the forward signal of the current digital channel to be processed in a vector manner, and add the results of each multiplication to obtain the pre-corrected forward signal.

[0142] In addition, in another example, the mutual coupling filtering module 903 is specifically configured to select the mutual coupling filtering parameters of each digital channel from a set of mutual coupling filtering parameters trained according to the feedback signals collected by a plurality of coupling dipoles according to the digital channel numbers and channel beam angles of the current digital channels; wherein, the set of mutual coupling filtering parameters includes: the mutual coupling filtering parameters corresponding to the combination of each digital channel number and each channel beam angle; and perform mutual coupling filtering processing on the forward signals of the current digital channels according to the selected mutual coupling filtering parameters of each digital channel.

[0143] In addition, the predistortion learning module 902 is specifically configured to construct a signal matrix W of the digital channel according to the distortion characteristics of the power amplifier output signal of the digital channel, using the forward signal of the digital channel and the feedback signals collected by the plurality of coupling dipoles j and a feedback signal matrix V j ; where j represents the channel number of the digital channel; according to the W j and the V j , obtain the mutual coupling filtering parameters of the digital channel and the power amplifier model coefficient c PA ; according to the mutual coupling filtering parameters of the digital channel and the power amplifier model coefficient c PA , reconstruct the far-field beam center signal; and train to obtain the candidate set of predistortion coefficients according to the forward signal of the digital channel, the reconstructed far-field beam center signal, and a preset training model.

[0144] It is not difficult to find that this embodiment is a device embodiment corresponding to the first or second embodiment, and this embodiment can be implemented in cooperation with the first or second embodiment. The relevant technical details mentioned in the first or second embodiment are still valid in this embodiment. To avoid repetition, they are not elaborated here. Accordingly, the relevant technical details mentioned in this embodiment can also be applied to the first or second embodiment.

[0145] It is worth mentioning that each module involved in this embodiment is a logic module. In practical applications, a logic unit can be a physical unit, a part of a physical unit, or a combination of multiple physical units. In addition, to highlight the innovative part of the present invention, units that are not closely related to solving the technical problems proposed by the present invention are not introduced in this embodiment, but this does not mean that there are no other units in this embodiment.

[0146] The fifth embodiment of the present invention relates to a non-volatile storage medium for storing computer-readable programs. The computer-readable programs are used for a computer to execute the signal distortion pre-correction method described in the above method embodiment.

[0147] That is, those skilled in the art can understand that all or part of the steps of implementing the methods in the above embodiments can be completed by instructing relevant hardware through a program. The program is stored in a storage medium and includes several instructions for causing a device (which can be a single-chip microcomputer, a chip, etc.) or a processor to execute all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs and other various media that can store program codes.

[0148] Those of ordinary skill in the art can understand that the above embodiments are specific embodiments for implementing the present invention, and in practical applications, various changes can be made in form and details without departing from the spirit and scope of the present invention.

Claims

1. A signal distortion pre - correction method, characterized in that, Including: Select the mutual coupling filtering parameters for each digital channel from the mutual coupling filtering parameter set trained based on the feedback signals collected by the multi-channel coupling dipoles according to the digital channel numbers and channel beam angles of the current digital channels; wherein, the mutual coupling filtering parameter set includes: mutual coupling filtering parameters corresponding to the combinations of each digital channel number and each channel beam angle. Perform mutual coupling filtering processing on the forward signals of the current digital channels according to the selected mutual coupling filtering parameters of the current digital channels. Select a target pre-distortion coefficient from the pre-distortion coefficient candidate set according to the forward signal of the current digital channel to be processed and the forward signals of the current digital channels after mutual coupling filtering processing; wherein, the pre-distortion coefficient candidate set is trained based on the feedback signals collected by the multi-channel coupling dipoles. Perform distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the target pre-distortion coefficient.

2. The signal distortion pre-correction method according to claim 1, characterized in that The pre-distortion coefficient candidate set includes a two-dimensional look-up table, and the two-dimensional look-up table is used to store the corresponding relationship between the combination of the forward signal modulus and the modulus of the forward signals of each digital channel after mutual coupling filtering, and the pre-distortion coefficient. The selecting a target pre-distortion coefficient from the pre-distortion coefficient candidate set includes: According to the modulus of the forward signal of the current digital channel to be processed and the modulus of the forward signals of the current digital channels after mutual coupling filtering processing, look up the two-dimensional look-up table to obtain the corresponding pre-distortion coefficient as the target pre-distortion coefficient.

3. The signal distortion pre-correction method according to claim 2, wherein The pre-distortion coefficient candidate set includes multiple two-dimensional look-up tables corresponding to different signal delays. The looking up the two-dimensional look-up table includes: According to the modulus of the forward signal of the current digital channel to be processed and the modulus of the forward signals of the current digital channels after mutual coupling filtering processing, respectively look up each two-dimensional look-up table to obtain the corresponding pre-distortion coefficients in each two-dimensional look-up table as the target pre-distortion coefficients respectively. The performing distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the target pre-distortion coefficient includes: Multiply the corresponding pre-distortion coefficients found in each two-dimensional look-up table vectorially with the forward signal of the current digital channel to be processed respectively, and add the results of each multiplication to obtain a pre-corrected forward signal.

4. The signal distortion pre-correction method according to any one of claims 1 to 3, characterized in that, The pre-distortion coefficient candidate set is trained based on the feedback signals collected by the multi-channel coupling dipoles, including: According to the distortion characteristics of the power amplifier output signal of the digital channel, the signal matrix W of the digital channel is constructed by using the forward signal of the digital channel and the feedback signal collected by the multi-channel coupling array. j And the feedback signal matrix V j ; Wherein, j represents the channel number of the digital channel; According to the said W j and the said V j , obtain the mutual coupling filter parameters of the digital channel and the power amplifier model coefficient c PA ; According to the de-beamforming matrix and the power amplifier model coefficient c PA , reconstruct the far-field beam center signal; Training the pre-distortion coefficient candidate set according to the forward signal of the digital channel, the reconstructed far-field beam center signal, and a preset training model.

5. The signal distortion pre-correction method according to any one of claims 1 to 3, characterized in that The multi-channel coupling dipoles are arranged inside the whole machine radome or on the antenna substrate at the near-field position outside the antenna.

6. The signal distortion pre - correction method according to any one of claims 1 to 3, characterized in that, After performing distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the target pre-distortion coefficient, it further includes: Performing digital-to-analog conversion on the forward signal after distortion pre-compensation processing to obtain an analog signal. Performing analog beamforming processing on the analog signal. Performing power amplification processing on the output signal after analog beamforming processing to generate a radio frequency signal meeting the power requirements. Transmit the radio frequency signal through the antenna element array layout.

7. A signal distortion pre-correction device, characterized in that, Comprising: A coupled signal feedback control module, a predistortion learning module, a mutual coupling filtering module, and a predistortion module. The coupled signal feedback control module is connected to the predistortion learning module. The predistortion learning module is respectively connected to the mutual coupling filtering module and the predistortion module. The mutual coupling filtering module is connected to the predistortion module; The coupled signal feedback control module is configured to obtain the feedback signals collected by multiple coupled dipoles and transmit the feedback signals to the predistortion learning module; The predistortion learning module is configured to train mutual coupling filtering parameters and a candidate set of predistortion coefficients based on the feedback signals collected by the multiple coupled dipoles, and transmit the mutual coupling filtering parameters to the mutual coupling filtering module and transmit the candidate set of predistortion coefficients to the predistortion module; The mutual coupling filtering module is configured to select the mutual coupling filtering parameters of each digital channel according to the digital channel numbers and the channel beam angles of the current digital channels in the mutual coupling filtering parameter set trained based on the feedback signals collected by the multiple coupled dipoles. Wherein, the mutual coupling filtering parameter set includes: mutual coupling filtering parameters corresponding to the combinations of each digital channel number and each channel beam angle. According to the selected mutual coupling filtering parameters of each digital channel, perform mutual coupling filtering processing on the forward signals of the current digital channels and transmit the forward signals of the current digital channels after the mutual coupling filtering processing to the predistortion module; The predistortion module is configured to select a target predistortion coefficient from the candidate set of predistortion coefficients according to the forward signal of the current digital channel to be processed and the forward signals of the current digital channels after the mutual coupling filtering processing, and perform distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the target predistortion coefficient.

8. The signal distortion pre-correction device according to claim 7, wherein, Comprising: The candidate set of predistortion coefficients includes a two-dimensional look-up table, and the two-dimensional look-up table is used to store the corresponding relationship between the combination of the modulus of the forward signal and the modulus of the forward signals of each digital channel after mutual coupling filtering and the predistortion coefficient; The predistortion module is specifically configured to look up the two-dimensional look-up table according to the modulus of the forward signal of the current digital channel to be processed and the modulus of the forward signals of the current digital channels after the mutual coupling filtering processing to obtain the corresponding predistortion coefficient as the target predistortion coefficient, and perform distortion pre-compensation processing on the forward signal of the current digital channel to be processed according to the target predistortion coefficient.

9. A non-volatile storage medium for storing computer-readable programs, characterized in that, The computer-readable program is used for a computer to execute the signal distortion pre-correction method according to any one of claims 1 to 6.

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