Receiving processing device and program

Abstract

The present invention provides a receiving processing device and program that can improve the accuracy of nonlinear distortion compensation on the receiving side. [Solution] A receiving processing device that performs receiving processing based on a received signal comprises a parameter learning unit that learns parameters and a nonlinear distortion compensation unit that compensates for the nonlinear distortion of the target signal using the parameters. The parameter learning unit comprises a nonlinear calculation unit that performs the same nonlinear calculation as a nonlinear circuit on an input signal and outputs the calculation result, a band limiting unit that performs band limiting processing on the calculation result output from the nonlinear calculation unit and outputs the signal after band limiting processing, and a parameter calculation unit that calculates the parameters such that the error between the signal obtained when the signal after band limiting processing and a reference signal are linearly combined using the same linear combination method as the linear circuit of the nonlinear distortion compensation unit and the reference signal is minimized.

Description

Technical Field

[0001] The present disclosure relates to a reception processing apparatus and a program.

Background Art

[0002] Techniques for compensating for non-linear distortion of a transmission signal generated by non-linear amplification characteristics of a power amplifier of a wireless transmission apparatus on the transmission side have been proposed (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Non-Patent Documents

[0004]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, the same technology as DPD (Digital Pre-Distortion) on the transmission side can be applied to non-linear distortion compensation processing on the reception side. However, the inventor has found that, unlike the transmission side, if parameters used for non-linear distortion compensation are calculated based on a signal including non-linear distortion components outside the signal band that ultimately becomes unnecessary, effective parameters for non-linear distortion compensation cannot be calculated, and the non-linear distortion compensation accuracy may deteriorate.

[0006] An object of the present disclosure is to provide a reception processing apparatus and a program capable of improving the accuracy of non-linear distortion compensation on the reception side. It should be noted that this object is only one of the multiple objects that the multiple embodiments disclosed in this specification are intended to achieve. Other objects or problems and novel features will be clarified from the description of this specification or the attached drawings.

Means for Solving the Problem

[0007] A reception processing apparatus according to the present disclosure is a reception processing apparatus that performs reception processing based on a reception signal, and includes a parameter learning unit that learns parameters, and a non-linear distortion compensation unit that compensates for non-linear distortion of a target signal using the parameters. The non-linear distortion compensation unit includes Q (Q is an integer of 2 or more) first non-linear operation units each of which performs a non-linear operation on the target signal and outputs an operation result, and a linear operation unit that forms a distortion-compensated signal by performing a linear combination process based on the Q output signals output from the Q first non-linear operation units and outputs the distortion-compensated signal. The parameter learning unit includes Q second non-linear operation units each of which performs the same non-linear operation as the Q first non-linear operation units on an input signal and outputs Q operation results, Q first band limitation units each of which performs a band limitation process on each of the Q operation results output from the Q second non-linear operation units and outputs Q signals after the band limitation process, and a parameter calculation unit that calculates the parameters so that an error between a signal obtained by linearly combining the Q signals after the band limitation process by the same linear combination method as the linear operation unit and a reference signal is minimized using the Q signals after the band limitation process and the reference signal. Each first band limitation unit has a band limitation characteristic of having a pass band including a signal band of a modulation signal of a wireless transmission apparatus that transmitted a signal corresponding to the reception signal and blocking frequency components outside the pass band.

[0008] The program relating to this disclosure is a program that causes a receiving processing device that performs receiving processing based on a received signal to execute processing including learning parameters and compensating for the nonlinear distortion of a target signal using the parameters, wherein the compensation for the nonlinear distortion includes each of Q (where Q is an integer of 2 or more) first nonlinear calculation units performing nonlinear calculations on the target signal and outputting the calculation results, and a linear calculation unit forming a distortion-compensated signal by performing linear combination processing based on the Q output signals output from the Q first nonlinear calculation units, wherein the learning of parameters includes the Q first nonlinear calculation units for the input signal The process includes: performing the same nonlinear calculations as the linear calculation unit to output Q calculation results; performing a band-limiting process on each of the Q calculation results to output Q band-limiting signals; and calculating the parameters such that the error between the signal obtained when the Q band-limiting signals are linearly combined using the same linear combination method as the linear calculation unit and the reference signal is minimized, wherein the band-limiting process allows frequency components within the passband, which includes the signal band of the modulated signal of the wireless transmitter that transmitted the signal corresponding to the received signal, to pass through, and blocks frequency components outside the passband. [Effects of the Invention]

[0009] This disclosure provides a receiving processing device and program that can improve the accuracy of nonlinear distortion compensation on the receiving side. [Brief explanation of the drawing]

[0010] [Figure 1] A list of examples of receiving processing devices in this disclosure. [Figure 2] This flowchart shows an example of the processing operation of the receiving device in this disclosure. [Figure 3] Another example of a receiving processing device in this disclosure is shown in the viewport. [Figure 4] Another example of a receiving processing device in this disclosure is shown in the viewport. [Figure 5]Another example of a receiving processing device in this disclosure is shown in the viewport. [Figure 6] Another example of a receiving processing device in this disclosure is shown in the viewport. [Figure 7] Another example of a receiving processing device in this disclosure is shown in the viewport. [Figure 8] Another example of a receiving processing device in this disclosure is shown in the viewport. [Figure 9] Another example of a receiving processing device in this disclosure is shown in the viewport. [Figure 10] Another example of a receiving processing device in this disclosure is shown in the viewport. [Figure 11] This figure shows an example of the configuration of a receiving device. [Modes for carrying out the invention]

[0011] The embodiments will be described below with reference to the drawings. In this disclosure, the drawings may be associated with one or more embodiments. Also, each element in the drawings may correspond to one or more embodiments. Furthermore, in the embodiments, the same or equivalent elements are denoted by the same reference numerals, and redundant descriptions are omitted.

[0012] <First Embodiment> <Example configuration of a receiving device> Figure 1 is a block diagram showing an example of a receiving processing device according to the present disclosure. In Figure 1, the receiving processing device 10 includes a nonlinear distortion compensation unit 11 and a parameter learning unit 12. The receiving processing device 10 is used, for example, mounted on a wireless receiving device (not shown).

[0013] The nonlinear distortion compensation unit 11 compensates for the nonlinear distortion of the signal to be subjected to distortion compensation (hereinafter sometimes simply referred to as the "target signal") using the parameters calculated by the parameter learning unit 12. The target signal is, for example, a signal based on a received signal that is wirelessly transmitted from a wireless transmitter (not shown) after the modulated signal has been amplified by a power amplifier of a wireless transmitter (not shown) and then wirelessly received by the wireless receiver (not shown). For this reason, the target signal contains nonlinear distortion components.

[0014] For example, as shown in Figure 1, the nonlinear distortion compensation unit 11 has nonlinear circuits 11A-1 to 11A-Q and a linear circuit 11B. In the following, when the nonlinear circuits 11A-1 to 11A-Q are not distinguished, each of the nonlinear circuits 11A-1 to 11A-Q, or the nonlinear circuits 11A-1 to 11A-Q collectively, may be simply referred to as the nonlinear circuit 11A. Q is an integer of 2 or more. That is, the nonlinear distortion compensation unit 11 has a plurality of nonlinear circuits 11A. In the following, the functional parts constituting the nonlinear distortion compensation unit will be mainly described as being configured as circuits, but this disclosure is not limited to this. The functional parts constituting the nonlinear distortion compensation unit may be realized by a processor reading and executing a program stored in memory.

[0015] Each nonlinear circuit 11A performs a nonlinear operation on the target signal and outputs the obtained operation result to the linear circuit 11B. For example, if the nonlinear distortion compensation unit 11 performs distortion compensation processing based on a polynomial model of distortion, the Q nonlinear circuits 11A each correspond to the Q orders in the polynomial model. That is, each nonlinear circuit 11A performs a nonlinear operation corresponding to the order of the polynomial model to which each nonlinear circuit 11A corresponds.

[0016] The linear circuit 11B forms a distortion-compensated signal by performing a linear combination process based on the Q output signals output from the Q nonlinear circuits 11A, and outputs the formed distortion-compensated signal.

[0017] The parameter learning unit 12 calculates the parameters used in the nonlinear strain compensation unit 11.

[0018] For example, as shown in Figure 1, the parameter learning unit 12 includes nonlinear calculation units 12A-1 to 12A-Q, bandwidth limiting units 12B-1 to 12B-Q, and a parameter calculation unit 12C. In the following, when the nonlinear calculation units 12A-1 to 12A-Q are not distinguished, each of the nonlinear calculation units 12A-1 to 12A-Q, or the nonlinear calculation units 12A-1 to 12A-Q collectively, may be simply referred to as the nonlinear calculation unit 12A. When the bandwidth limiting units 12B-1 to 12B-Q are not distinguished, each of the bandwidth limiting units 12B-1 to 12B-Q, or the bandwidth limiting units 12B-1 to 12B-Q collectively, may be simply referred to as the bandwidth limiting unit 12B.

[0019] The nonlinear calculation units 12A-1 to 12A-Q correspond to the band limiting units 12B-1 to 12B-Q, respectively. Furthermore, the nonlinear calculation units 12A-1 to 12A-Q correspond to the nonlinear circuits 11A-1 to 11A-Q, respectively.

[0020] Each nonlinear calculation unit 12A performs the same nonlinear calculation as the corresponding nonlinear circuit 11A on the "input signal" and outputs the obtained calculation result to the corresponding band limiting unit 12B. The "input signal" is, for example, a signal based on a received signal that has been amplified by a power amplifier of a wireless transmitter (not shown), then wirelessly transmitted from the wireless transmitter (not shown), and wirelessly received by the wireless receiver (not shown).

[0021] Each bandwidth limiting unit 12B performs bandwidth limiting on the calculation result received from the corresponding nonlinear calculation unit 12A and outputs the bandwidth-limited signal to the parameter calculation unit 12C. Each bandwidth limiting unit 12B may have a bandwidth limiting characteristic that includes a passband that includes the signal bandwidth (ROF band) of the modulated signal of the wireless transmitter (not shown) and blocks frequency components outside the passband. For example, each bandwidth limiting unit 12B may have a passband wider than the signal bandwidth (ROF band) of the modulated signal of the wireless transmitter (not shown) (for example, a passband 1.2 times wider than the ROF band).

[0022] The parameter calculation unit 12C uses the Q bandwidth-limited signals output from the bandwidth-limited units 12B-1 to 12B-Q and the "reference signal" to calculate the parameters used in the nonlinear distortion compensation process in the nonlinear distortion compensation unit 11 so as to minimize the error between the signal obtained by linearly combining the Q bandwidth-limited signals using the same linear combination method as the linear circuit 11B and the reference signal. The "reference signal" is a signal based on the modulated signal of a wireless transmitter (not shown), and is a signal based on the ideal signal when the modulated signal is received without containing nonlinear distortion components.

[0023] The parameter calculation unit 12C may use, for example, LS (Least Squares), LMS (Least Mean Squares), or RLS (Recursive Least Squares) as an adaptive algorithm.

[0024] <Example of operation of the receiving device> Figure 2 is a flowchart showing an example of the processing operation of the receiving device of this disclosure.

[0025] In the receiving processing device 10, the nonlinear calculation units 12A-1 to 12A-Q perform nonlinear calculations on the input signal (step S11). This input signal is a signal based on a received signal that is wirelessly transmitted from a wireless transmitter (not shown) and wirelessly received by a wireless receiver (not shown) from a modulated signal of a known signal. The known signal is known between the wireless transmitter (not shown) and the receiving processing device 10 (wireless receiver (not shown)).

[0026] The bandwidth limiting units 12B-1 to 12B-Q perform bandwidth limiting processing on each of the Q calculation results received from the nonlinear calculation units 12A-1 to 12A-Q (step S12).

[0027] The parameter calculation unit 12C calculates the parameters using the Q bandwidth-limited signals output from the bandwidth-limiting units 12B-1 to 12B-Q and the "reference signal" (step S13). These calculated parameters are set in the nonlinear distortion compensation unit 11. The reference signal is a signal based on the known signals mentioned above.

[0028] The nonlinear distortion compensation unit 11 compensates for the nonlinear distortion of the "target signal" using the set parameters (step S14). This target signal is a signal based on a received signal, which is wirelessly transmitted from a wireless transmitter (not shown) and wirelessly received by a wireless receiver (not shown) from a modulated data signal.

[0029] As described above, according to the first embodiment, in the receiving processing device 10, each nonlinear calculation unit 12A performs the same nonlinear calculation as the corresponding nonlinear circuit 11A on the "input signal" and outputs the obtained calculation result to the corresponding band limiting unit 12B. Each band limiting unit 12B performs band limiting processing on the calculation result received from the corresponding nonlinear calculation unit 12A and outputs the signal after band limiting processing to the parameter calculation unit 12C. The parameter calculation unit 12C uses the Q band-limited signals output from the band limiting units 12B-1 to 12B-Q and the "reference signal" to calculate parameters such that the error between the signal obtained when the Q band-limited signals are linearly combined using the same linear combination method as the linear circuit 11B and the reference signal is minimized. Each band limiting unit 12B has a passband that includes the signal band of the modulated signal of the wireless transmitter (not shown) and has a band limiting characteristic that blocks frequency components outside the passband.

[0030] The configuration of this receiving processing device 10 allows for the calculation of parameters based on the signal from which frequency components outside the signal band of the modulated signal of the wireless transmitting device (not shown) have been removed. As a result, parameters effective for nonlinear distortion compensation can be calculated. Consequently, the accuracy of nonlinear distortion compensation on the receiving side can be improved.

[0031] <Second Embodiment> The second embodiment describes a case in which a polynomial model of strain is applied to the nonlinear strain compensation unit and the parameter learning unit. Since the basic configuration of the receiving device in the second embodiment is the same as that of the receiving device 10 in the first embodiment, it will be explained with reference to Figure 1.

[0032] In the receiving processing device 10 of the second embodiment, the processing by the nonlinear distortion compensation unit 11 can be expressed by the following equation (1).

number

[0033] In equation (1), the part expressed by equation (2) below represents the output from the nonlinear circuit 11A of the order corresponding to q.

number

[0034] In other words, for example, the linear circuit 11B has a tapped delay line corresponding to each nonlinear circuit 11A. Furthermore, the linear circuit 11B connects the output from each nonlinear circuit 11A to parameter C for each tap. qm It has a multiplier that multiplies by and . It also has a first adder that adds the signal obtained by the multiplier for each tap. It also has a second adder that adds the signal obtained by the first adder for each tap for all taps. Note that parameter C qm This is the distortion compensation coefficient.

[0035] The nonlinear calculation unit 12A-q (where q is one of 1 to Q) outputs the signal represented by equation (2) above. In this case, x(k) in equation (2) corresponds to the "input signal" above.

[0036] Then, the band-limiting unit 12B-q performs band-limiting processing represented by the following equation (3).

Equation

[0037] Then, the parameter calculation unit 12C calculates a parameter (distortion compensation coefficient C qm ) so that the value of the following equation (4) becomes minimum, for example, by the least squares method (LS: Least Squares).

Equation

[0038] <Third Embodiment> The third embodiment will explain the case where a DPD (Digital Pre-Distortion) technique using a neural network is used for the non-linear distortion compensation unit and the parameter learning unit. Here, in particular, the explanation will be made on the premise of the case of the ETDNN (Envelope Time-Delay Neural Network) described in Non-Patent Document 1.

[0039] FIG. 3 is a block diagram showing another example of the reception processing apparatus of the present disclosure. In FIG. 3, the reception processing apparatus 20 includes a non-linear distortion compensation unit 11, a parameter learning unit 12, and a pre-learning unit 21.

[0040] The pre-learning unit 21 calculates parameters (w l,j (1) , b j (1) ) used by the non-linear circuit 11A and the parameter learning unit 12. Also, the parameter learning unit 12 of the third embodiment has parameters (w j,m(2) ,b m (2) Calculate b. m (2) This is used in the nonlinear circuit 11A, w j,m (2) This is used in linear circuit 11B. Here, w l,j (1) b is the real-valued weight between the input layer and the hidden layer. j (1) w is the real-valued bias between the input layer and the hidden layer. j,m (2) b is the complex-valued weight between the hidden layer and the output layer. m (2) w is a complex-valued bias between the hidden layer and the output layer. l,j (1) ,b j (1) ,w j,m (2) ,b m (2) For further details, please refer to Non-Patent Document 1.

[0041] The pre-learning unit 21 includes, for example, Q nonlinear calculation units (not shown) corresponding to the nonlinear circuits 11A-1 to 11A-Q, a linear calculation unit (not shown) corresponding to the linear circuit 11B, and a parameter calculation unit (not shown). The parameter calculation unit (not shown) of the pre-learning unit 21 uses the calculation results obtained by the linear calculation unit (not shown) and the reference signal to calculate the parameters (w) using the backpropagation method. l,j (1) ,b j (1) The parameter (w) is calculated using the backpropagation method. j,m (2) ,b m (2) ) will also be calculated, but this parameter will not be used. The parameter (w calculated in the pre-training unit 21) l,j (1) ,b j (1) The output is sent to the parameter learning unit 12 and the nonlinear distortion compensation unit 11.

[0042] In the receiving processing device 20 of the third embodiment, the processing by the nonlinear distortion compensation unit 11 can be expressed by the following equation (5).

number

[0043] In equation (5), the part represented by equation (6) below represents the output from the nonlinear circuit 11A. That is, the upper part of equation (6) below is w j,m (2) Corresponding to this, the lower part of equation (6) below is b m (2) It corresponds to.

number

[0044] Furthermore, the part of equation (5) represented by equation (7) below represents the processing in the linear circuit 11B.

number

[0045] The output of the nonlinear calculation unit 12A in the receiving processing unit 20 is expressed by the following equations (8) and (9). Equation (8) is: w j,m (2) Corresponding to this, equation (9) is, b m (2) It corresponds to.

number

number

[0046] Then, the bandwidth limiting unit 12B-q performs the bandwidth limiting process represented by equation (3) above.

[0047] Then, the parameter calculation unit 12C calculates the parameter (distortion compensation coefficient C) such that the value of equation (10) below is minimized, for example, by the least squares method (LS). qm Calculate ).

number

[0048] z'(k) in equation (10) is expressed by the following equation (11).

number

[0049] Furthermore, the techniques described above can also be applied to RVTDNN (Real-Valued Time-Delay Neural Network). Furthermore, with regard to DPD using neural networks, the computational load can be reduced by applying pruning (reducing unnecessary connections) during the learning process, and embodiments that apply pruning are also possible.

[0050] <Fourth Embodiment> The fourth embodiment relates to a variation in which a bandwidth limiting unit is provided in the output stage of the nonlinear distortion compensation unit.

[0051] Figure 4 is a block diagram showing another example of the receiving processing device of the present disclosure. In Figure 4, the receiving processing device 30 includes a nonlinear distortion compensation unit 11, a parameter learning unit 12, and a bandwidth limiting unit 31.

[0052] The bandwidth limiting unit 31 is located in the output stage of the nonlinear distortion compensation unit 11. The bandwidth limiting unit 31 performs bandwidth limiting on the distortion-compensated signal output from the nonlinear distortion compensation unit 11.

[0053] The bandwidth limiting unit 31 may have a receive ROF characteristic. When a 50 / 50 distribution is made between a wireless transmitter (not shown) and a wireless receiver (not shown), the bandwidth limiting unit 31 has a 50% receive ROF characteristic. The passband of the bandwidth limiting unit 12B is, for example, wider than the signal bandwidth (ROF bandwidth) of the modulated signal of the wireless transmitter (not shown).

[0054] <Fifth Embodiment> The fifth embodiment relates to a variation in which a bandwidth limiting unit is provided at the input stage of the parameter learning unit.

[0055] Figure 5 is a block diagram showing another example of the receiving processing device of the present disclosure. In Figure 5, the receiving processing device 40 includes a nonlinear distortion compensation unit 11, a parameter learning unit 12, a bandwidth limiting unit 31, and a bandwidth limiting unit 41.

[0056] The bandwidth limiting unit 41 is located at the input stage of the parameter learning unit 12. The bandwidth limiting unit 41 performs bandwidth limiting on the received signal and outputs the received signal after bandwidth limiting to the parameter learning unit 12.

[0057] The bandwidth limiting unit 41 may have a passband wider than the signal bandwidth (ROF bandwidth) of the modulated signal of the wireless transmitter (not shown). The bandwidth limiting unit 31 may have a received ROF characteristic. The passband of the bandwidth limiting unit 12B is, for example, wider than the signal bandwidth (ROF bandwidth) of the modulated signal of the wireless transmitter (not shown).

[0058] In the example shown in Figure 5, the receiving processing device 40 has a bandwidth limiting unit 31, but the disclosure is not limited thereto, and the receiving processing device 40 does not have to have a bandwidth limiting unit 31.

[0059] <Sixth Embodiment> The sixth embodiment relates to a variation in which a bandwidth limiting unit is provided at the input stage of the nonlinear distortion compensation unit and the parameter learning unit.

[0060] Figure 6 is a block diagram showing another example of the receiving processing device of the present disclosure. In Figure 6, the receiving processing device 50 includes a nonlinear distortion compensation unit 11, a parameter learning unit 12, a bandwidth limiting unit 31, and a bandwidth limiting unit 51.

[0061] The bandwidth limiting unit 51 is located at the input stage of the nonlinear distortion compensation unit 11 and the parameter learning unit 12. The bandwidth limiting unit 51 performs bandwidth limiting on the received signal and outputs the received signal after bandwidth limiting to the nonlinear distortion compensation unit 11 and the parameter learning unit 12.

[0062] The bandwidth limiting unit 51 may have a receive ROF characteristic. When a 50 / 50 distribution is made between a wireless transmitter (not shown) and a wireless receiver (not shown), the bandwidth limiting unit 51 has a 50% receive ROF characteristic. The passband of the bandwidth limiting unit 12B is wider than, for example, the signal bandwidth (ROF bandwidth) of the modulated signal of the wireless transmitter (not shown). The passband of the bandwidth limiting unit 31 is wider than, for example, the signal bandwidth (ROF bandwidth) of the modulated signal of the wireless transmitter (not shown).

[0063] Here, the reference signal input to the parameter calculation unit 12C is the signal obtained when the above ideal signal is passed through a filter with a 50% receiver ROF characteristic.

[0064] In the example shown in Figure 6, the receiving processing device 50 has a bandwidth limiting unit 31, but the disclosure is not limited thereto, and the receiving processing device 50 does not have to have a bandwidth limiting unit 31.

[0065] <Seventh Embodiment> The seventh embodiment relates to a variation in which a band-limiting circuit is arranged between a nonlinear circuit and a linear circuit in the nonlinear distortion compensation unit.

[0066] Figure 7 is a block diagram showing another example of the receiving processing device of the present disclosure. In Figure 7, the receiving processing device 60 includes a nonlinear strain compensation unit 61 and a parameter learning unit 12.

[0067] The nonlinear distortion compensation unit 61 and the nonlinear distortion compensation unit 11 compensate for the nonlinear distortion of the target signal using the parameters calculated by the parameter learning unit 12.

[0068] The nonlinear distortion compensation unit 61 includes nonlinear circuits 11A-1 to 11A-Q, band-limiting circuits 61A-1 to 61A-Q, and a linear circuit 11B. In the following, when the band-limiting circuits 61A-1 to 61A-Q are not distinguished, each of the band-limiting circuits 61A-1 to 61A-Q, or the band-limiting circuits 61A-1 to 61A-Q collectively, may be simply referred to as the band-limiting circuit 61A.

[0069] The band-limiting circuits 61A-1 to 61A-Q correspond to the nonlinear circuits 11A-1 to 11A-Q, respectively. The band-limiting circuits 61A-1 to 61A-Q perform band-limiting processing on each of the Q calculation results output from the nonlinear circuits 11A-1 to 11A-Q, and output the Q band-limited signals to the linear circuit 11B as the target of linear combination processing of the linear circuit 11B.

[0070] Each band-limiting circuit 61A performs band-limiting processing on the calculation result received from the corresponding nonlinear circuit 11A and outputs the band-limited signal to the linear circuit 11B. Each band-limiting circuit 61A may have a band-limiting characteristic that includes a passband that includes the signal bandwidth (ROF band) of the modulated signal of the wireless transmitter (not shown) and blocks frequency components outside the passband. For example, each band-limiting circuit 61A may have a passband wider than the signal bandwidth (ROF band) of the modulated signal of the wireless transmitter (not shown) (for example, a passband 1.2 times wider than the ROF band). In this case, the above-mentioned ideal signal is used as the reference signal input to the parameter calculation unit 12C. Alternatively, for example, if single-carrier modulation such as PSK (phase-shift keying), QAM (Quadrature Amplitude Modulation), or APSK (Amplitude and phase-shift keying) is performed by the wireless transmitter (not shown), the band-limiting circuit 61A may have a received ROF characteristic. When a 50 / 50 distribution is made between a wireless transmitter (not shown) and a wireless receiver (not shown), each band limiting circuit 61A has a 50% receive ROF characteristic. In this case, the reference signal input to the parameter calculation unit 12C is the signal obtained when the above-mentioned ideal signal is passed through a filter with a 50% receive ROF characteristic.

[0071] In other words, the function of the set of nonlinear circuits 11A-1 to 11A-Q and band-limiting circuits 61A-1 to 61A-Q is the same as the function of the set of nonlinear calculation units 12A-1 to 12A-Q and band-limiting units 12B-1 to 12B-Q. For this reason, the receiving processing device 60 may have a configuration that has one of the sets of nonlinear circuits 11A-1 to 11A-Q and band-limiting circuits 61A-1 to 61A-Q and the set of nonlinear calculation units 12A-1 to 12A-Q and band-limiting units 12B-1 to 12B-Q, but does not have the other. For example, if the receiving processing device 60 has a set of nonlinear circuits 11A-1 to 11A-Q and band-limiting circuits 61A-1 to 61A-Q, that is, if the nonlinear circuits 11A-1 to 11A-Q and band-limiting circuits 61A-1 to 61A-Q also function as nonlinear calculation units 12A-1 to 12A-Q and band-limiting units 12B-1 to 12B-Q, the outputs of the band-limiting circuits 61A-1 to 61A-Q may be output not only to the linear circuit 11B but also to the parameter calculation unit 12C. The configuration of this receiving processing device will be described in the eighth embodiment.

[0072] Furthermore, if the receiving processing device 60 has a set of nonlinear calculation units 12A-1 to 12A-Q and bandwidth limiting units 12B-1 to 12B-Q, the outputs of the bandwidth limiting units 12B-1 to 12B-Q may be output not only to the parameter calculation unit 12C but also to the linear circuit 11B.

[0073] In the example shown in Figure 7, the input and output stages of the nonlinear distortion compensation unit 61 do not have bandwidth limiting units, but this disclosure is not limited thereto. The receiving processing unit 60 may be provided with bandwidth limiting units similar to the bandwidth limiting units 31, 41, and 51 of the fourth to sixth embodiments. In this case, the received ROF characteristics may be distributed as in the ninth and tenth embodiments described later. In this case, the reference signal is the same as in the ninth and tenth embodiments described later.

[0074] <Eighth Embodiment> The eighth embodiment relates to another variation in which a band-limiting circuit is arranged between the nonlinear circuit and the linear circuit in the nonlinear distortion compensation unit.

[0075] Figure 8 is a block diagram showing another example of the receiving processing device of the present disclosure. In Figure 8, the receiving processing device 70 includes a nonlinear distortion compensation unit 61 and a parameter learning unit 71.

[0076] The parameter learning unit 71 includes a parameter calculation unit 71A. The parameter calculation unit 71A uses the Q bandwidth-limited signals output from the bandwidth-limited units 12B-1 to 12B-Q and a "reference signal" to calculate the parameters used in the nonlinear distortion compensation unit 61 so as to minimize the error between the signal obtained when the Q bandwidth-limited signals are linearly combined using the same linear combination method as the linear circuit 11B and the reference signal.

[0077] <Ninth Embodiment> The ninth embodiment relates to a variation in which a bandwidth limiting unit is provided at the input stage of the nonlinear distortion compensation unit.

[0078] Figure 9 is a block diagram showing another example of the receiving processing device of the present disclosure. In Figure 9, the receiving processing device 80 includes a nonlinear distortion compensation unit 61, a parameter learning unit 71, and a bandwidth limiting unit 81.

[0079] The bandwidth limiting unit 81 is located at the input stage of the nonlinear distortion compensation unit 61. The bandwidth limiting unit 81 performs bandwidth limiting on the received signal and outputs the received signal after bandwidth limiting to the nonlinear distortion compensation unit 61.

[0080] The bandwidth limiting unit 81 may have a passband wider than the signal bandwidth (ROF bandwidth) of the modulated signal of the wireless transmitter (not shown). The bandwidth limiting circuit 61A may also have a receive ROF characteristic. When a 50 / 50 distribution is made between the wireless transmitter (not shown) and the wireless receiver (not shown), the bandwidth limiting circuit 61A has a 50% receive ROF characteristic.

[0081] Alternatively, the bandwidth limiting unit 81 and the bandwidth limiting circuit 61A may have a received ROF characteristic. When a 50 / 50 distribution is made between a wireless transmitter (not shown) and a wireless receiver (not shown), 50% of the received ROF characteristic is distributed to the bandwidth limiting unit 81 and the bandwidth limiting circuit 61A. For example, 25% of the received ROF characteristic may be distributed to the bandwidth limiting unit 81 and 25% to the bandwidth limiting circuit 61A.

[0082] Here, the reference signal input to the parameter calculation unit 71A is the signal obtained when the above-mentioned ideal signal is passed through a filter with a 50% receiving ROF characteristic.

[0083] <Tenth Embodiment> The tenth embodiment relates to a variation in which a bandwidth limiting unit is provided in the output stage of the nonlinear distortion compensation unit.

[0084] Figure 10 is a block diagram showing another example of the receiving processing device of the present disclosure. In Figure 10, the receiving processing device 90 includes a nonlinear distortion compensation unit 61, a parameter learning unit 71, a bandwidth limiting unit 91, and a bandwidth limiting unit 92.

[0085] The bandwidth limiting unit 91 is located at the input stage of the nonlinear distortion compensation unit 61. The bandwidth limiting unit 91 performs bandwidth limiting on the received signal and outputs the received signal after bandwidth limiting to the nonlinear distortion compensation unit 61 as the target signal.

[0086] The bandwidth limiting unit 92 is located in the output stage of the nonlinear distortion compensation unit 61. The bandwidth limiting unit 92 performs bandwidth limiting on the distortion-compensated signal output from the nonlinear distortion compensation unit 61.

[0087] The band limiting units 91 and 92 may each have a passband wider than the signal bandwidth (ROF bandwidth) of the modulated signal of the wireless transmitter (not shown). The band limiting circuit 61A may also have a receive ROF characteristic. When a 50 / 50 distribution is made between the wireless transmitter (not shown) and the wireless receiver (not shown), the band limiting circuit 61A has a 50% receive ROF characteristic. In this case, the reference signal input to the parameter calculation unit 71A is the signal obtained when the above-mentioned ideal signal is passed through a filter with a 50% receive ROF characteristic.

[0088] Alternatively, the band limiting unit 91 and the band limiting circuit 61A may have a receive ROF characteristic. When a 50 / 50 distribution is made between a wireless transmitter (not shown) and a wireless receiver (not shown), 50% of the receive ROF characteristic is distributed to the band limiting unit 91 and the band limiting circuit 61A. For example, 25% of the receive ROF characteristic may be distributed to the band limiting unit 91 and 25% to the band limiting circuit 61A. In this case, the reference signal input to the parameter calculation unit 71A is the signal obtained when the above-mentioned ideal signal is passed through a filter with a 50% receive ROF characteristic. Alternatively, for example, 20% of the receive ROF characteristic may be distributed to the band limiting unit 91 and 30% of the receive ROF characteristic may be distributed to the band limiting circuit 61A. Furthermore, the band limiting unit 92 may have a passband wider than the signal bandwidth (ROF bandwidth) of the modulated signal of the wireless transmitter (not shown). In this case, the reference signal input to the parameter calculation unit 71A is the signal obtained when the above-mentioned ideal signal is passed through a filter with a 50% receiving ROF characteristic.

[0089] Alternatively, the band-limiting units 91, 92 and the band-limiting circuit 61A may have a receive ROF characteristic. When a 50 / 50 distribution is made between a wireless transmitter (not shown) and a wireless receiver (not shown), 50% of the receive ROF characteristic is distributed to the band-limiting units 91, 92 and the band-limiting circuit 61A. For example, 20% of the receive ROF characteristic may be distributed to the band-limiting unit 91, 20% to the band-limiting circuit 61A, and 10% to the band-limiting unit 92. In this case, the reference signal input to the parameter calculation unit 71A is the signal obtained when the above ideal signal is passed through a filter with a 40% receive ROF characteristic. Alternatively, for example, 10% of the receive ROF characteristic may be distributed to the band-limiting unit 91, 20% to the band-limiting circuit 61A, and 20% to the band-limiting unit 92. In this case, the reference signal input to the parameter calculation unit 71A is the signal obtained when the above-mentioned ideal signal is passed through a filter with a 30% receiving ROF characteristic.

[0090] In the example shown in Figure 10, the receiving processing device 90 has bandwidth limiting units 91 and 92, but the disclosure is not limited thereto, and the receiving processing device 90 does not need to have one of the bandwidth limiting units 91 or 92.

[0091] <Other Embodiments> Figure 11 shows an example configuration of a receiving device. In Figure 11, the receiving device 100 includes a processor 101 and a memory 102. The processor 101 may be, for example, a microprocessor, an MPU (Micro Processing Unit), or a CPU (Central Processing Unit). The processor 101 may include multiple processors. The memory 102 is composed of a combination of volatile memory and non-volatile memory. The memory 102 may include storage located away from the processor 101. In this case, the processor 101 may access the memory 102 via an I(Input) / O(Output) interface, which is not shown.

[0092] The receiving processing devices 10, 20, 30, 40, 50, 60, 70, 80, and 90 of the first to tenth embodiments can each have the configuration shown in Figure 11. The nonlinear distortion compensation units 11 and 61, parameter learning units 12 and 71, pre-learning unit 21, and bandwidth limiting units 31, 41, 51, 81, 91, and 92 of the receiving processing devices 10, 20, 30, 40, 50, 60, 70, 80, and 90 of the first to tenth embodiments may be implemented by the processor 101 reading and executing a program stored in memory 102. In other words, the receiving processing devices 10, 20, 30, 40, 50, 60, 70, 80, and 90 of the first to tenth embodiments can be implemented in software. The program can be stored using various types of non-transitory computer-readable medium and supplied to the receiving processing units 10, 20, 30, 40, 50, 60, 70, 80, and 90 of the first to tenth embodiments. Examples of non-transitory computer-readable medium include magnetic recording media (e.g., flexible disks, magnetic tapes, hard disk drives) and magneto-optical recording media (e.g., magneto-optical disks). Furthermore, examples of non-transitory computer-readable medium include CD-ROMs (Read Only Memory), CD-Rs, and CD-R / Ws. Further examples of non-transitory computer-readable medium include semiconductor memory. Semiconductor memory includes, for example, mask ROMs, PROMs (Programmable ROMs), EPROMs (Erasable PROMs), flash ROMs, and RAMs (Random Access Memory). Furthermore, the program may be supplied to the receiving devices 10, 20, 30, 40, 50, 60, 70, 80, and 90 of the first to tenth embodiments by various types of transient computer-readable medium. Examples of transient computer-readable medium include electrical signals, optical signals, and electromagnetic waves. The transient computer-readable medium can supply the program to the receiving devices 10, 20, 30, 40, 50, 60, 70, 80, and 90 of the first to tenth embodiments via wired communication channels such as electric wires and optical fibers, or via wireless communication channels.

[0093] Alternatively, the nonlinear distortion compensation units 11, 61, parameter learning units 12, 71, pre-learning unit 21, and bandwidth limiting units 31, 41, 51, 81, 91, 92 of the receiving processing units 10, 20, 30, 40, 50, 60, 70, 80, 90 of the first to tenth embodiments may each be implemented with dedicated hardware. Furthermore, some or all of the components of each device may be implemented by general-purpose or dedicated circuits, processors, etc., or combinations thereof. These may be configured by a single chip or by multiple chips connected via a bus. Some or all of the components of each device may be implemented by a combination of the above-mentioned circuits, etc., and programs. In addition, a CPU (Central Processing Unit), GPU (Graphics Processing Unit), FPGA (field-programmable gate array), quantum processor (quantum computer control chip), etc. can be used as the processor.

[0094] Although the present invention has been described above with reference to embodiments, the present invention is not limited thereto. Various modifications to the structure and details of the present invention can be made within the scope of the invention as can be understood by those skilled in the art. Furthermore, each embodiment can be combined with other embodiments as appropriate.

[0095] Each drawing is merely illustrative to illustrate one or more embodiments. Each drawing may be associated with one or more other embodiments rather than with only one specific embodiment. As those skilled in the art will understand, various features or steps described with reference to any one drawing can be combined with features or steps shown in one or more other drawings, for example, to create embodiments not explicitly shown or described. Not all features or steps shown in any one drawing to illustrate an exemplary embodiment are necessarily required, and some features or steps may be omitted. The order of steps shown in any of the drawings may be changed as appropriate.

[0096] Some or all of the above embodiments may also be described as follows, but are not limited to the following: (Note 1) A receiving processing device that performs receiving processing based on a received signal, A parameter learning unit that learns parameters, A nonlinear distortion compensation unit that compensates for the nonlinear distortion of the target signal using the aforementioned parameters, It is equipped with, The aforementioned nonlinear distortion compensation unit is Q (where Q is an integer of 2 or more) first nonlinear calculation units, each first nonlinear calculation unit, performs a nonlinear calculation on the target signal and outputs the calculation result, A linear calculation unit that forms a distortion-compensated signal by performing a linear combination process based on the Q output signals output from the Q first nonlinear calculation units, and outputs the distortion-compensated signal, It is equipped with, The parameter learning unit, Q second nonlinear calculation units, each second nonlinear calculation unit, performs the same nonlinear calculation as the Q first nonlinear calculation units on an input signal and outputs Q calculation results. Q first band-limiting units each perform band-limiting on the Q calculation results output from the Q second nonlinear calculation units and output Q signals after the band-limiting process, A parameter calculation unit calculates the parameters such that the error between the signal obtained when the Q bandwidth-limited signals are linearly combined using the same linear combination method as the linear calculation unit and the reference signal is minimized. It is equipped with, Each first band limiting unit has a passband that includes the signal bandwidth of the modulated signal of the wireless transmitter that transmitted the signal corresponding to the received signal, and has a band limiting characteristic that blocks frequency components outside the passband. Receiving processing device. (Note 2) The system further comprises one or both of the following: a second band limiting unit that performs band limiting on the received signal and outputs the received signal after band limiting as the target signal to the nonlinear distortion compensation unit and as the input signal to the parameter learning unit; and a fourth band limiting unit provided in the output stage of the nonlinear distortion compensation unit and performing band limiting on the distortion-compensated signal. The receiving processing device described in Appendix 1. (Note 3) The system further comprises one or both of the following: a third band limiting unit provided at the input stage of the parameter learning unit, which performs band limiting processing on the received signal and outputs the received signal after band limiting processing to the parameter learning unit; and a fourth band limiting unit provided at the output stage of the nonlinear distortion compensation unit, which performs band limiting processing on the distortion-compensated signal. The receiving processing device described in Appendix 1. (Note 4) The nonlinear distortion compensation unit is provided between each of the Q first nonlinear calculation units and the linear calculation unit, and further comprises Q fifth band limiting units that perform band limiting on each of the Q calculation results output from the Q first nonlinear calculation units, and output the Q band-limited signals to the linear calculation unit as the target of the linear combination processing of the linear calculation unit. The receiving processing device described in Appendix 1. (Note 5) The Q first nonlinear calculation units and the Q fifth band limiting units function as the Q second nonlinear calculation units and the Q first band limiting units of the parameter learning unit. The receiving processing device described in Appendix 4. (Note 6) The system further comprises one or both of the following: a second band limiting unit that performs band limiting on the received signal and outputs the received signal after band limiting as the target signal to the nonlinear distortion compensation unit; and a fourth band limiting unit provided in the output stage of the nonlinear distortion compensation unit and performing band limiting on the distortion-compensated signal. The Q fifth band-limiting units and either or both of the second band-limiting unit or the fourth band-limiting unit are distributed such that their overall characteristics result in a received ROF (Roll Off Filter) characteristic. The receiving processing device described in Appendix 5. (Note 7) The aforementioned reference signal includes: If the second band limiting unit does not have a received ROF characteristic, the received ROF characteristics distributed to the Q fifth band limiting units are applied. If the second band-limiting unit has a receive ROF characteristic, both the receive ROF characteristics distributed to the Q fifth band-limiting units and the receive ROF characteristics distributed to the second band-limiting unit are applied. The receiving processing device described in Appendix 6. (Note 8) The parameter calculation unit uses LS (Least Squares), LMS (Least Mean Squares), or RLS (Recursive Least Squares) as an adaptive algorithm. The receiving processing device described in Appendix 1. (Note 9) The Q first nonlinear calculation units each correspond to the Q orders in the polynomial model of the strain, The Q second nonlinear calculation units correspond to the Q orders, The receiving processing device described in Appendix 1. (Note 10) The aforementioned polynomial model is a memory polynomial model, a generalized memory polynomial model, or a memoryless polynomial model. The receiving processing device described in Appendix 9. (Note 11) The Q first nonlinear computation units perform calculations using the outputs of the Q nodes in the intermediate layer of a DPD (Digital Pre-Distortion) using a neural network. The Q second nonlinear calculation units perform calculations using the outputs of the Q nodes. The receiving processing device described in Appendix 1. (Note 12) A method performed by a receiving processing device that performs receiving processing based on a received signal, Learning the parameters, Using the aforementioned parameters, the nonlinear distortion of the target signal is compensated, Includes, Compensating for the aforementioned nonlinear distortion is Each of the Q (where Q is an integer greater than or equal to 2) first nonlinear calculation units performs a nonlinear calculation on the target signal and outputs the calculation result. The linear calculation unit forms a distortion-compensated signal by performing a linear combination process based on the Q output signals output from the Q first nonlinear calculation units, Includes, Learning the aforementioned parameters means Performing the same nonlinear calculation as the Q first nonlinear calculation units on the input signal and outputting Q calculation results, The process involves applying a bandwidth limiting process to each of the Q calculation results and outputting the Q signals after bandwidth limiting. The parameters are calculated such that the error between the signal obtained by linearly combining the Q bandwidth-limited signals and the reference signal using the same linear combination method as the linear calculation unit is minimized. Includes, The aforementioned bandwidth limiting process allows frequency components within a passband that includes the signal bandwidth of the modulated signal of the wireless transmitter that transmitted the signal corresponding to the received signal to pass through, and blocks frequency components outside the passband. method. (Note 13) A receiving processing device that performs receiving processing based on the received signal, Learning the parameters, Using the aforementioned parameters, the nonlinear distortion of the target signal is compensated, A program that includes and performs processing, Compensating for the aforementioned nonlinear distortion is Each of the Q (where Q is an integer greater than or equal to 2) first nonlinear calculation units performs a nonlinear calculation on the target signal and outputs the calculation result. The linear calculation unit forms a distortion-compensated signal by performing a linear combination process based on the Q output signals output from the Q first nonlinear calculation units, Includes, Learning the aforementioned parameters means Performing the same nonlinear calculation as the Q first nonlinear calculation units on the input signal and outputting Q calculation results, The process involves applying a bandwidth limiting process to each of the Q calculation results and outputting the Q signals after bandwidth limiting. The parameters are calculated such that the error between the signal obtained by linearly combining the Q bandwidth-limited signals and the reference signal using the same linear combination method as the linear calculation unit is minimized. Includes, The aforementioned bandwidth limiting process allows frequency components within a passband that includes the signal bandwidth of the modulated signal of the wireless transmitter that transmitted the signal corresponding to the received signal to pass through, and blocks frequency components outside the passband. program. (Note 14) A receiving processing device that performs receiving processing based on a received signal, A parameter learning unit that learns parameters, A nonlinear distortion compensation unit that compensates for the nonlinear distortion of the target signal using the aforementioned parameters, It is equipped with, The aforementioned nonlinear distortion compensation unit is Each nonlinear calculation unit performs a nonlinear calculation on the target signal and outputs the calculation result. Q (where Q is an integer of 2 or more) nonlinear calculation units, Q first band-limiting units perform band-limiting processing on each of the Q calculation results output from the Q nonlinear calculation units and output Q signals after the band-limiting processing. A linear calculation unit that forms a distortion-compensated signal by performing a linear combination process based on the Q bandwidth-limited signals and outputs the distortion-compensated signal, It is equipped with, The parameter learning unit, A parameter calculation unit calculates update parameters such that the error between the signal obtained when the Q bandwidth-limited signals are linearly combined using the same linear combination method as the linear calculation unit and the reference signal is minimized. It is equipped with, Each first band limiting unit has a passband that includes the signal bandwidth of the modulated signal of the wireless transmitter that transmitted the signal corresponding to the received signal, and has a band limiting characteristic that blocks frequency components outside the passband. Receiving processing device. (Note 15) The Q first band-limiting units have a received ROF (Roll Off Filter) characteristic as their band-limiting characteristic. The receiving processing device described in Appendix 14. (Note 16) The system further comprises one or both of the following: a second band limiting unit that performs band limiting on the received signal and outputs the received signal after band limiting as the target signal to the nonlinear distortion compensation unit; and a third band limiting unit provided in the output stage of the nonlinear distortion compensation unit and performing band limiting on the distortion-compensated signal. The receiving processing device described in Appendix 14. (Note 17) The Q first band limiting units and either or both of the second band limiting unit or the third band limiting unit are distributed such that their overall characteristics result in a received ROF characteristic. The receiving processing device described in Appendix 16. (Note 18) The aforementioned reference signal includes: If the second bandwidth limiting unit is not provided, the received ROF characteristics distributed to the Q first bandwidth limiting units are applied. If the second bandwidth limiting unit is provided, both the received ROF characteristics distributed to the Q first bandwidth limiting units and the received ROF characteristics distributed to the second bandwidth limiting unit are applied. The receiving processing device described in Appendix 17. (Note 19) The parameter calculation unit uses LS (Least Squares), LMS (Least Mean Squares), or RLS (Recursive Least Squares) as an adaptive algorithm. The receiving processing device described in Appendix 14. (Note 20) The Q nonlinear operation units correspond to the Q orders in the polynomial model of the strain, The receiving processing device described in Appendix 14. (Note 21) The aforementioned polynomial model is a memory polynomial model, a generalized memory polynomial model, or a memoryless polynomial model. The receiving processing device described in Appendix 20. (Note 22) The aforementioned Q nonlinear computation units perform calculations using the outputs of the Q nodes in the intermediate layer of a DPD (Digital Pre-Distortion) using a neural network. The receiving processing device described in Appendix 14. (Note 23) A method performed by a receiving processing device that performs receiving processing based on a received signal, Learning the parameters, Using the aforementioned parameters, the nonlinear distortion of the target signal is compensated, Includes, Compensating for the aforementioned nonlinear distortion is Each of the Q (where Q is an integer greater than or equal to 2) nonlinear calculation units performs a nonlinear calculation on the target signal and outputs the calculation result. Q first bandwidth limiting units each perform bandwidth limiting on the Q calculation results and output Q bandwidth-limited signals. The linear calculation unit forms a distortion-compensated signal by performing a linear combination process based on the Q band-limited signals, Includes, Learning the parameters includes calculating update parameters such that the error between the signal obtained by linearly combining the Q band-limited signals and the reference signal using the same linear combination method as the linear calculation unit is minimized. Each first band limiting unit has a passband that includes the signal bandwidth of the modulated signal of the wireless transmitter that transmitted the signal corresponding to the received signal, and has a band limiting characteristic that blocks frequency components outside the passband. method. (Note 24) A receiving processing device that performs receiving processing based on the received signal, Learning the parameters, Using the aforementioned parameters, the nonlinear distortion of the target signal is compensated, A program that includes and performs processing, Compensating for the aforementioned nonlinear distortion is Each of the Q (where Q is an integer greater than or equal to 2) nonlinear calculation units performs a nonlinear calculation on the target signal and outputs the calculation result. Q first bandwidth limiting units perform bandwidth limiting on each of the Q calculation results and output Q signals after bandwidth limiting. The linear calculation unit forms a distortion-compensated signal by performing a linear combination process based on the Q band-limited signals, Includes, Learning the parameters includes calculating update parameters such that the error between the signal obtained by linearly combining the Q band-limited signals and the reference signal using the same linear combination method as the linear calculation unit is minimized. Each first band limiting unit has a passband that includes the signal bandwidth of the modulated signal of the wireless transmitter that transmitted the signal corresponding to the received signal, and has a band limiting characteristic that blocks frequency components outside the passband. program. [Explanation of Symbols]

[0097] 10 Receiving Processing Unit 11 Nonlinear distortion compensation section 11A Nonlinear Circuit 11B Linear circuit 12 Parameter Learning Unit 12A Nonlinear Calculation Unit 12B Bandwidth Limiting Section 12C Parameter Calculation Unit 20 Receiving Processing Unit 21 Pre-learning Section 30 Receiving Processing Unit 31 Bandwidth Limiting Section 40 Receiving Processing Unit 41 Bandwidth limiting section 50 Receiving Processing Unit 51 Bandwidth Limiting Section 60 Receiving Processing Unit 61 Nonlinear Distortion Compensation Section 61A Bandwidth Limiting Circuit 70 Receiving Processing Unit 71 Parameter Learning Unit 71A Parameter calculation unit 80 Receiving Processing Unit 81 Bandwidth Limiting Section 90 Receiving Processing Unit 91 Bandwidth Limiting Section 92 Bandwidth Limiting Section

Claims

1. A receiving processing device that performs receiving processing based on a received signal, A parameter learning unit that learns parameters, A nonlinear distortion compensation unit that compensates for the nonlinear distortion of the target signal using the aforementioned parameters, It is equipped with, The aforementioned nonlinear distortion compensation unit is Q (where Q is an integer of 2 or more) first nonlinear calculation units each perform a nonlinear calculation on the target signal and output the calculation result, A linear calculation unit that forms a distortion-compensated signal by performing linear combination processing based on the Q output signals output from the Q first nonlinear calculation units, and outputs the distortion-compensated signal, It is equipped with, The parameter learning unit, Q second nonlinear calculation units, each second nonlinear calculation unit, performs the same nonlinear calculation as the Q first nonlinear calculation units on an input signal and outputs Q calculation results, Q first band-limiting units each perform band-limiting on the Q calculation results output from the Q second nonlinear calculation units and output Q signals after the band-limiting process, A parameter calculation unit calculates the parameters such that the error between the signal obtained when the Q bandwidth-limited signals are linearly combined using the same linear combination method as the linear calculation unit and the reference signal is minimized. It is equipped with, Each first band limiting unit has a passband that includes the signal bandwidth of the modulated signal of the wireless transmitter that transmitted the signal corresponding to the received signal, and has a band limiting characteristic that blocks frequency components outside the passband. Receiving processing device.

2. The system further comprises one or both of the following: a second band limiting unit that performs band limiting on the received signal and outputs the received signal after band limiting as the target signal to the nonlinear distortion compensation unit and as the input signal to the parameter learning unit; and a fourth band limiting unit provided in the output stage of the nonlinear distortion compensation unit and performing band limiting on the distortion-compensated signal. The receiving processing device according to claim 1.

3. The system further comprises one or both of the following: a third band limiting unit provided at the input stage of the parameter learning unit, which performs band limiting on the received signal and outputs the received signal after band limiting to the parameter learning unit; and a fourth band limiting unit provided at the output stage of the nonlinear distortion compensation unit, which performs band limiting on the distortion-compensated signal. The receiving processing device according to claim 1.

4. The nonlinear distortion compensation unit is provided between each of the Q first nonlinear calculation units and the linear calculation unit, and further comprises Q fifth band limiting units that perform band limiting on each of the Q calculation results output from the Q first nonlinear calculation units, and output the Q band-limited signals to the linear calculation unit as the target of the linear combination processing of the linear calculation unit. The receiving processing device according to claim 1.

5. The Q first nonlinear calculation units and the Q fifth band limiting units function as the Q second nonlinear calculation units and the Q first band limiting units of the parameter learning unit. The receiving processing device according to claim 4.

6. The system further comprises one or both of the following: a second band limiting unit that performs band limiting on the received signal and outputs the received signal after band limiting as the target signal to the nonlinear distortion compensation unit; and a fourth band limiting unit provided in the output stage of the nonlinear distortion compensation unit and performing band limiting on the distortion-compensated signal. The Q fifth band limiting units and either or both of the second band limiting unit or the fourth band limiting unit are distributed such that their overall characteristics result in a received ROF (Roll Off Filter) characteristic. The receiving processing device according to claim 5.

7. The aforementioned reference signal includes: If the second bandwidth limiting unit does not have a receive ROF characteristic, the receive ROF characteristics distributed to the Q fifth bandwidth limiting units are applied. If the second bandwidth limiting unit has a receive ROF characteristic, both the receive ROF characteristics distributed to the Q fifth bandwidth limiting units and the receive ROF characteristics distributed to the second bandwidth limiting unit are applied. The receiving apparatus according to claim 6.

8. The Q first nonlinear calculation units each correspond to the Q orders in the polynomial model of the strain, The Q second nonlinear calculation units correspond to the Q orders, The receiving processing device according to claim 1.

9. The Q first nonlinear computation units perform calculations using the outputs of the Q nodes in the intermediate layer of a DPD (Digital Pre-Distortion) using a neural network. The Q second nonlinear calculation units perform calculations using the outputs of the Q nodes. The receiving processing device according to claim 1.

10. A receiving processing device that performs receiving processing based on the received signal, Learning the parameters, Using the aforementioned parameters, the nonlinear distortion of the target signal is compensated, A program that includes and performs processing, Compensating for the aforementioned nonlinear distortion is Each of the Q (where Q is an integer greater than or equal to 2) first nonlinear calculation units performs a nonlinear calculation on the target signal and outputs the calculation result, The linear calculation unit forms a distortion-compensated signal by performing a linear combination process based on the Q output signals output from the Q first nonlinear calculation units, Includes, Learning the aforementioned parameters means The input signal is subjected to the same nonlinear calculation as the Q first nonlinear calculation units, and Q calculation results are output. The process involves applying bandwidth limiting to each of the Q calculation results and outputting the Q signals after bandwidth limiting. The parameters are calculated such that the error between the signal obtained by linearly combining the Q bandwidth-limited signals and the reference signal using the same linear combination method as the linear calculation unit is minimized. Includes, The aforementioned bandwidth limiting process allows frequency components within a passband that includes the signal bandwidth of the modulated signal of the wireless transmitter that transmitted the signal corresponding to the received signal to pass through, and blocks frequency components outside the passband. program.

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