Signal Processing Method for Band-Limited Predistortion System and Band-Limited Predistortion System

Abstract

An embodiment of the present invention provides a signal processing method and a band-limited predistortion system for a band-limited predistortion system. The method includes: determining model parameters of a power amplifier model to be established based on historical original signals input to a digital-to-analog conversion and up-conversion module, historical feedback signals output by an analog-to-digital conversion and down-conversion module, a baseband response of a filter, a total order of the filter, and a preset band-limited predistortion system model; establishing a power amplifier model based on the model parameters; and determining a predistortion model based on the power amplifier model and the historical original signals, so that the signals obtained after the historical original signals pass through a predistorter and a power amplifier are linear with the original signals. Since the influence of the filter on the model memory depth is considered when establishing the power amplifier model, the obtained power amplifier model is more accurate, and further, when using the power amplifier model and the predistortion model to perform predistortion and amplification processing on signals, the linearization effect is better.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and particularly to a signal processing method for a band-limited predistortion system and a band-limited predistortion system. Background Art

[0002] Currently, in order to correct the nonlinear distortion generated by a signal passing through a power amplifier, signal linearization is required. Among linearization technologies, the predistortion technology is widely applied due to its characteristics such as low implementation complexity, high stability, wide bandwidth, and good linearization performance. Among them, this predistortion technology is to add a predistorter with characteristics opposite to those of the power amplifier at the front end of the power amplifier. The signal first passes through the predistorter for pre-distortion processing, and then the pre-distorted signal passes through the power amplifier. Since the characteristics of the predistorter and the power amplifier compensate each other, the output signal of the power amplifier will have a linear relationship with the original input signal, thereby realizing the linearization processing of the signal.

[0003] Subsequently, to solve the cost problem of the feedback loop ADC (Analog-to-Digital Converter), the band-limited predistortion technology was proposed. The band-limited predistortion technology restricts the sampling rate of the ADC by introducing a filter in the feedback loop. In the band-limited predistortion technology, the effect of realizing the linearization of the signal usually depends on the modeling accuracy of the power amplifier model. When the modeling accuracy of the power amplifier model is higher, the effect of linearizing the signal is better; otherwise, it will lead to a deterioration in the effect of linearizing the signal.

[0004] However, the inventor found that in the existing digital band-limited predistortion technology, the accuracy of the power amplifier model obtained after modeling by the currently proposed algorithms is not high, which will reduce the effect of linearizing the signal. Summary of the Invention

[0005] The purpose of the embodiments of the present invention is to provide a signal processing method for a band-limited predistortion system and a band-limited predistortion system to improve the effect of linearizing the signal. The specific technical solutions are as follows:

[0006] In a first aspect, the embodiments of the present invention provide a signal processing method for a band-limited predistortion system, which is applied to a band-limited predistortion system. The band-limited predistortion system includes: a predistorter, a digital-to-analog conversion and up-conversion module, a power amplifier, a coupler, a filter, an analog-to-digital conversion and down-conversion module, and a modeler; the predistorter, the digital-to-analog conversion and up-conversion module, the power amplifier, the coupler, the filter, the analog-to-digital conversion and down-conversion module, and the modeler are connected in sequence; the modeler is connected to the predistorter; the method includes:

[0007] The modeler obtains the historical original signal input to the digital-to-analog conversion and up-conversion module, the historical feedback signal output by the analog-to-digital conversion and down-conversion module, the baseband response of the filter, and the total order of the filter. The historical feedback signal is the signal output after the historical original signal passes through the digital-to-analog conversion and up-conversion module, power amplifier, coupler, filter, and analog-to-digital conversion and down-conversion module.

[0008] The modeler determines the model parameters of the power amplifier model to be established based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and the preset band-limited predistortion system model.

[0009] The modeler establishes a power amplifier model based on the model parameters; and determines the predistortion model corresponding to the predistorter based on the power amplifier model and the historical original signal.

[0010] The predistorter performs predistortion processing on the original signal to be distorted using the predistortion model, and inputs the predistorted signal to be amplified obtained by the processing into the power amplifier.

[0011] The power amplifier amplifies the predistorted signal to be amplified output by the predistorter.

[0012] Optionally, before determining the model parameters of the power amplifier model to be established based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and the preset band-limited predistortion system model, the method further includes:

[0013] Synchronize the historical original signal and the historical feedback signal to obtain the synchronized historical original signal and the synchronized historical feedback signal.

[0014] Determining the model parameters of the power amplifier model to be established based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and the preset band-limited predistortion system model includes:

[0015] Determine the model parameters of the power amplifier model to be established based on the synchronized historical original signal, synchronized historical feedback signal, baseband response of the filter, total order of the filter, and the preset band-limited predistortion system model.

[0016] Optionally, the preset band-limited predistortion system model is the following formula:

[0017]

[0018] Where is the feedback signal, w(p) is the baseband response of the filter, P is the total order of the filter, L a , L b and Lc are respectively the pre-set memory depth parameters, K a , K b and K c are respectively the pre-set orders, M b is the pre-set delay depth, M c is the pre-set leading depth; x(n - l1 - p) is the (l1 + p)-th time-delayed signal of the original signal x(n), x(n - l2 - p) is the (l2 + p)-th time-delayed signal of the original signal x(n), x(n - l2 - m2 - p) is the (l2 + m2 + p)-th time-delayed signal of the original signal x(n), x(n - l3 - p) is the (l3 + p)-th time-delayed signal of the original signal x(n), x(n - l3 + m3 - p) is the (l3 - m3 + p)-th time-delayed signal of the original signal x(n), r 1l , r 2l , r 3l , and are the model parameters of the pre-set band-limited predistortion system model;

[0019] The power amplifier model to be established is the following formula:

[0020]

[0021] wherein, is the full-band signal corresponding to the original signal output by the power amplifier, x(n - l1) is the l1-th time-delayed signal of the original signal x(n), x(n - l2) is the l2-th time-delayed signal of the original signal x(n), x(n - l2 - m2) is the (l2 + m2)-th time-delayed signal of the original signal x(n), x(n - l3) is the l3-th time-delayed signal of the original signal x(n), x(n - l3 + m3) is the (l3 - m3)-th time-delayed signal of the original signal x(n).

[0022] Optionally, based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and model parameters of the pre-set band-limited predistortion system model, determine the model parameters of the power amplifier model to be established, including:

[0023] Obtain the initial values of the model parameters and of, where the initial values are pre-set values;

[0024] Based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and model parameters of the pre-set band-limited predistortion system model and The initial value, and calculate the model parameters r of the preset band-limited predistortion system model through the preset band-limited predistortion system model 1l , r 2l and r 3l of the iterative value;

[0025] Based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and the model parameter r of the preset band-limited predistortion system model 1l , r 2l , r 3l , calculate the model parameters of the preset band-limited predistortion system model through the preset band-limited predistortion system model and of the iterative value;

[0026] When the iterative values of the model parameters r of the preset band-limited predistortion system model 1l , r 2l , r 3l , and reach the preset output conditions, use the iterative values of the model parameters r of the preset band-limited predistortion system model 1l , r 2l , r 3l , and as the model parameters of the power amplifier model to be established;

[0027] Otherwise, use the iterative values of the model parameters and as the initial values of the model parameters and of the preset band-limited predistortion system model, and execute the step of calculating the iterative values of the model parameters r of the preset band-limited predistortion system model based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and the initial values of the model parameters and of the preset band-limited predistortion system model through the preset band-limited predistortion system model 1l , r 2l and r 3l ;

[0028] Optionally, based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and the initial values of the model parameters and of the preset band-limited predistortion system model, calculate the model parameters r of the preset band-limited predistortion system model through the preset band-limited predistortion system model 1l , r 2l and r 3lThe iterative values include:

[0029] Based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and model parameters of the preset band-limited predistortion system model and The initial values of, pass through the preset band-limited predistortion system model, and use the least squares method to calculate the model parameter r of the preset band-limited predistortion system model 1l , r 2l and r 3l The iterative values of;

[0030] Based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and model parameter r of the preset band-limited predistortion system model 1l , r 2l , r 3l , pass through the preset band-limited predistortion system model to calculate the iterative values of the model parameters and The iterative values include:

[0031] Based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and model parameter r of the preset band-limited predistortion system model 1l , r 2l , r 3l , pass through the preset band-limited predistortion system model and use the least squares method to calculate the model parameters and The iterative values of.

[0032] In a second aspect, an embodiment of the present invention further provides a band-limited predistortion system. The band-limited predistortion system includes: a predistorter, a digital-to-analog conversion and up-conversion module, a power amplifier, a coupler, a filter, an analog-to-digital conversion and down-conversion module, and a modeler; the predistorter, the digital-to-analog conversion and up-conversion module, the power amplifier, the coupler, the filter, the analog-to-digital conversion and down-conversion module, and the modeler are connected in sequence; the modeler is connected to the predistorter;

[0033] The modeler is configured to: obtain the historical original signal input into the digital-to-analog conversion and up-conversion module, the historical feedback signal output by the analog-to-digital conversion and down-conversion module, the baseband response of the filter, and the total order of the filter, where the historical feedback signal is the signal output after the historical original signal passes through the digital-to-analog conversion and up-conversion module, the power amplifier, the coupler, the filter, and the analog-to-digital conversion and down-conversion module;

[0034] The modeler is further configured to: determine the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model;

[0035] The modeler is further configured to: establish a power amplifier model based on the model parameters; and determine the predistortion model corresponding to the predistortion device based on the power amplifier model and the historical original signal;

[0036] The predistortion device is configured to perform predistortion processing on the original signal to be distorted by using the predistortion model, and input the predistorted signal to be amplified obtained by the processing into the power amplifier;

[0037] The power amplifier is configured to amplify the predistorted signal to be amplified output by the predistortion device.

[0038] Optionally, the modeler is further configured to:

[0039] Before determining the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model, synchronize the historical original signal and the historical feedback signal to obtain the synchronized historical original signal and the synchronized historical feedback signal;

[0040] The modeler is further configured to:

[0041] Determine the model parameters of the power amplifier model to be established based on the synchronized historical original signal, the synchronized historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model.

[0042] Optionally, the preset band-limited predistortion system model is the following formula:

[0043]

[0044] Wherein, is the feedback signal, w(p) is the baseband response of the filter, P is the total order of the filter, L a , L b and L c are respectively the preset memory depth parameters, K a , K b and K c are respectively the preset orders, M b is the preset delay depth, M cis the preset leading depth; x(n - l1 - p) is the (l1 + p)-th time-delayed signal of the original signal x(n), x(n - l2 - p) is the (l2 + p)-th time-delayed signal of the original signal x(n), x(n - l2 - m2 - p) is the (l2 + m2 + p)-th time-delayed signal of the original signal x(n), x(n - l3 - p) is the (l3 + p)-th time-delayed signal of the original signal x(n), x(n - l3 + m3 - p) is the (l3 - m3 + p)-th time-delayed signal of the original signal x(n), r 1l , r 2l , r 3l , and are the model parameters of the preset band-limited predistortion system model;

[0045] The power amplifier model to be established is as follows:

[0046]

[0047] Wherein, is the full-band signal corresponding to the original signal output by the power amplifier, x(n - l1) is the l1-th time-delayed signal of the original signal x(n), x(n - l2) is the l2-th time-delayed signal of the original signal x(n), x(n - l2 - m2) is the (l2 + m2)-th time-delayed signal of the original signal x(n), x(n - l3) is the l3-th time-delayed signal of the original signal x(n), x(n - l3 + m3) is the (l3 - m3)-th time-delayed signal of the original signal x(n).

[0048] Optionally, the modeler is specifically used for:

[0049] Obtain the initial values of the model parameters of the preset band-limited predistortion system model, wherein the initial values are preset values; and Based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and model parameters of the preset band-limited predistortion system model

[0050] and the initial values of and calculate the iterative values of the model parameters r 1l , r 2l and r 3l of the preset band-limited predistortion system model through the preset band-limited predistortion system model;

[0051] Based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and model parameters r 1l , r 2l , r3l , calculate the model parameters of the preset band-limited predistortion system model by presetting the band-limited predistortion system model and the iterative values;

[0052] Among the model parameters r of the preset band-limited predistortion system model 1l , r 2l , r 3l , and when the iterative values reach the preset output conditions, use the model parameters r of the preset band-limited predistortion system model 1l , r 2l , r 3l , and the iterative values as the model parameters of the power amplifier model to be established;

[0053] Otherwise, use the iterative values of the model parameters of the preset band-limited predistortion system model and as the initial values of the model parameters of the preset band-limited predistortion system model and , and execute based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and the initial values of the model parameters of the preset band-limited predistortion system model and , calculate the iterative values of the model parameters r of the preset band-limited predistortion system model through the preset band-limited predistortion system model 1l , r 2l and r 3l steps.

[0054] Optionally, the modeler is specifically used for:

[0055] Based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and the model parameters of the preset band-limited predistortion system model and initial values, calculate the iterative values of the model parameters r of the preset band-limited predistortion system model through the preset band-limited predistortion system model and using the least squares method 1l , r 2l and r 3l iterative values;

[0056] Based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and the model parameters r of the preset band-limited predistortion system model 1l , r 2l , r 3l, by presetting a band-limited predistortion system model and using the least squares method to calculate the model parameters of the preset band-limited predistortion system model and the iteration value of.

[0057] Beneficial effects of the embodiments of the present invention:

[0058] A signal processing method and a band-limited predistortion system for a band-limited predistortion system provided by an embodiment of the present invention. The modeler can first obtain the historical original signal input to the digital-to-analog conversion and up-conversion module, the historical feedback signal output by the analog-to-digital conversion and down-conversion module, the baseband response of the filter, and the total order of the filter. Then, based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model, the modeler determines the model parameters of the preset band-limited predistortion system model. In this way, the model parameters of the preset band-limited predistortion system model can be determined as the model parameters of the power amplifier model to be established, and thus the power amplifier model can be established based on the model parameters of the power amplifier model to be established; after the power amplifier model is established, the full-band signal corresponding to the historical original signal can be obtained through the power amplifier model, and then the predistortion model can be constructed according to the historical original signal and the calculated full-band signal. Finally, the signal obtained by passing the signal to be distorted through the predistorter and the power amplifier is linear with the signal to be distorted itself. Since in the embodiments of the present invention, when establishing the power amplifier model, the influence of the filter order on the model memory depth is considered, and the coefficients related to the model memory depth are calculated separately, so that the process of solving the power amplifier model is not easily interfered by the filter. Therefore, the modeled power amplifier model is more accurate, and further, when using the power amplifier model and the predistortion model to perform predistortion and amplification processing on the signal, the linearization effect is better. And when the filter bandwidth is narrow, a more accurate power amplifier model can be obtained than the traditional method, and further, the sampling rate of the necessary analog-to-digital converter in the feedback loop can be reduced, saving engineering costs. Of course, any product or method implementing the present invention does not necessarily need to achieve all the above advantages at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other embodiments can be obtained based on these drawings without creative efforts.

[0060] Figure 1 FIG. 20 is a schematic structural diagram of a band-limited predistortion system in the prior art;

[0061] Figure 2 Flow chart of the first implementation manner of a signal processing method for a band-limited predistortion system according to an embodiment of the present invention;

[0062] Figure 3 Flow chart of the second implementation manner of a signal processing method for a band-limited predistortion system according to an embodiment of the present invention;

[0063] Figure 4 Flow chart of the third implementation manner of a signal processing method for a band-limited predistortion system according to an embodiment of the present invention. Specific implementation manner

[0064] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art based on this application belong to the scope of protection of the present invention.

[0065] In the prior art, when preprocessing and amplifying a signal, a Figure 1 band-limited predistortion system as shown is usually adopted, such as Figure 1 shown. This system mainly includes: a predistorter 110, a digital-to-analog conversion and up-conversion module 120, a power amplifier 130, a coupler 140, a filter 150, an analog-to-digital conversion and down-conversion module 160, and a modeler 170. The predistorter 110, the digital-to-analog conversion and up-conversion module 120, the power amplifier 130, the coupler 140, the filter 150, the analog-to-digital conversion and down-conversion module 160, and the modeler 170 are connected in sequence; the modeler 170 is also connected to the predistorter 110; the input signal x(n) passes through the predistorter 110 to obtain a predistorted signal z(n). After being converted and up-converted by the digital-to-analog conversion and up-conversion module 120, the predistorted signal z(n) becomes the input signal Z RF (t) of the power amplifier 130. After being amplified by the power amplifier 130, the output signal y(t) is obtained. After the output signal y(t) is input to the coupler 140, the coupler divides the output signal y(t) output by the power amplifier into two signals. One signal is for output, and the other signal passes through the coupler 140 with a gain of 1 / k (k is the desired gain of the power amplifier) and then is input to the filter 150. The signal after being filtered by the filter 150 is then converted and down-converted by the analog-to-digital conversion and down-conversion module 160 to become the output signal of the feedback loop After that, the signal Enter the modeler 170 and calculate the pre-distorter coefficients in combination with the original input x(n), so as to linearize the signal.

[0066] However, in the prior art, when the passband of the filter 150 is very narrow, the modeling accuracy of the power amplifier model will rapidly decrease as the passband of the filter narrows. Since the bandwidth of the filter 150 is directly related to the minimum sampling rate of the analog-to-digital conversion and down-conversion module 160 in the feedback loop of the band-limited digital pre-distortion technology, in the prior art, when the sampling rate of the analog-to-digital conversion and down-conversion module 160 is low, it will lead to an ill-conditioned matrix in the calculation process, resulting in a decrease in the modeling accuracy of the power amplifier model, and further reducing the effect of the linearization process of the signal.

[0067] To solve the problems existing in the prior art, an embodiment of the present invention provides a signal processing method and a band-limited pre-distortion system for a band-limited pre-distortion system to improve the effect of signal linearization processing.

[0068] Next, a signal processing method for a band-limited pre-distortion system according to an embodiment of the present invention will be introduced. As Figure 2 shown, it is a schematic flowchart of the first implementation manner of a signal processing method for a band-limited pre-distortion system according to an embodiment of the present invention. This method can be applied to Figure 1 the band-limited pre-distortion system shown. This method may include:

[0069] S210, the modeler obtains the historical original signal input to the digital-to-analog conversion and up-conversion module, the historical feedback signal output by the analog-to-digital conversion and down-conversion module, the baseband response of the filter, and the total order of the filter. The historical feedback signal is the signal output after the historical original signal passes through the digital-to-analog conversion and up-conversion module, the power amplifier, the coupler, the filter, and the analog-to-digital conversion and down-conversion module;

[0070] S220, the modeler determines the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited pre-distortion system model;

[0071] S230, the modeler establishes a power amplifier model based on the model parameters; and determines the pre-distortion model corresponding to the pre-distorter based on the power amplifier model and the historical original signal;

[0072] S240, the pre-distorter performs pre-distortion processing on the original signal to be distorted using the pre-distortion model, and inputs the pre-distorted signal to be amplified obtained by the processing into the power amplifier;

[0073] S250, the power amplifier amplifies the pre-distorted signal to be amplified output by the pre-distorter.

[0074] In some examples, when a signal is input into the band-limited pre-distortion system, at the initial stage, the pre-distorter 110 does not perform pre-distortion. Therefore, it can be assumed that the pre-distorter 110 is a linear device first. Thus, the signal input into the pre-distorter 110 is equal to the signal output by the pre-distorter, that is, x(n)=z(n). The signal passes through the pre-distorter 110 to obtain the pre-distorted signal z(n). After digital-to-analog conversion and up-conversion module 120, the pre-distorted signal z(n) becomes the input signal Z RF (t) of the power amplifier 130. After being amplified by the power amplifier 130, the output signal y(t) is input into the filter 150 after passing through the coupler 140 with a gain of 1 / k (k is the desired gain of the power amplifier). The signal After passing through the analog-to-digital conversion and down-conversion module 160, it becomes the output signal of the feedback loop Therefore, after inputting the historical original signal into the band-limited pre-distortion system, the historical feedback signal corresponding to the historical original signal output by the analog-to-digital conversion and down-conversion module 160 can be obtained.

[0075] In some examples, the digital-to-analog conversion and up-conversion module 120 includes a digital-to-analog converter and an up-converter, and the analog-to-digital conversion and down-conversion module 160 includes an analog-to-digital converter and a down-converter.

[0076] To improve the modeling accuracy of the power amplifier model and thus improve the effect of signal linearization processing, the historical original signal input into the digital-to-analog converter, the baseband response of the filter, and the total order of the filter can also be obtained here. The filter baseband response is: the unit impulse response of the radio frequency band-pass filter converted into a finite impulse response filter on the equivalent baseband.

[0077] After obtaining the historical original signal, historical feedback signal, filter baseband response, and total order of the filter, the model parameters of the preset band-limited pre-distortion system model can be determined based on the historical original signal, historical feedback signal, filter baseband response, total order of the filter, and the preset band-limited pre-distortion system model. Then, the model parameters of the preset band-limited pre-distortion system model are used as the model parameters of the power amplifier model to be established. In this way, the power amplifier model can be established based on the model parameters of the power amplifier model to be established. After establishing the power amplifier model, the pre-distortion model corresponding to the pre-distorter can also be determined based on the power amplifier model and the historical original signal;

[0078] In some examples, when determining the predistortion model corresponding to the predistorter based on the power amplifier model and the historical original signal, the established power amplifier model and the historical original signal can be used to calculate the full-band output signal of the power amplifier, and then the predistortion model can be constructed based on the historical original signal and the calculated full-band output signal.

[0079] In some examples, the basis functions adopted by the predistortion model are the same as those of the power amplifier model. Therefore, when determining the predistortion model corresponding to the predistorter based on the power amplifier model and the historical original signal, it can be based on the full-band output of the power amplifier obtained from the power amplifier model and the historical original signal to calculate the parameters adopted by the predistortion model. After calculating the parameters adopted by the predistortion model, the parameters can be substituted into the formula adopted by the predistortion model, so that the predistortion model can be obtained.

[0080] After obtaining the predistortion model and the power amplification model, the predistorter can use the predistortion model to perform predistortion processing on the original signal to be distorted, and input the predistorted signal to be amplified obtained by the processing into the power amplifier; the power amplifier can perform amplification processing on the predistorted signal to be amplified output by the predistorter. Finally, the amplified signal output by the power amplifier is linear with the original input signal.

[0081] A signal processing method for a band-limited predistortion system provided by an embodiment of the present invention. The modeler can first obtain the historical original signal input to the digital-to-analog conversion and up-conversion module, the historical feedback signal output by the analog-to-digital conversion and down-conversion module, the baseband response of the filter, and the total order of the filter. Then, based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and a preset band-limited predistortion system model, the modeler determines the model parameters of the preset band-limited predistortion system model. In this way, the model parameters of the preset band-limited predistortion system model can be determined as the model parameters of the power amplifier model to be established, and thus a power amplifier model can be established based on the model parameters of the power amplifier model to be established. After the power amplifier model is established, the full-band signal corresponding to the historical original signal can be obtained through the power amplifier model, and then a predistortion model can be constructed according to the historical original signal and the calculated full-band signal. Finally, the signal obtained by passing the signal to be distorted through the predistorter and the power amplifier is linear with the signal to be distorted itself. Since in the embodiment of the present invention, when establishing the power amplifier model, the influence of the filter order on the model memory depth is considered, and the coefficients related to the model memory depth are calculated separately, the process of solving the power amplifier model is not easily interfered by the filter. Therefore, the modeled power amplifier model is more accurate. Furthermore, when the filter bandwidth is narrow, a more accurate power amplifier model can be obtained than the traditional method, and thus the sampling rate of the necessary analog-to-digital converter in the feedback loop can be reduced, saving engineering costs.

[0082] Based on Figure 2 the signal processing method for a band-limited predistortion system shown above, an embodiment of the present invention further provides a possible implementation manner, as Figure 3 shown, which is a flowchart of a second implementation manner of the signal processing method for a band-limited predistortion system according to an embodiment of the present invention. The method may include:

[0083] S310. The modeler obtains the historical original signal input to the digital-to-analog conversion and up-conversion module, the historical feedback signal output by the analog-to-digital conversion and down-conversion module, the baseband response of the filter, and the total order of the filter, where the historical feedback signal is the signal output after the historical original signal passes through the digital-to-analog conversion and up-conversion module, the power amplifier, the coupler, the filter, and the analog-to-digital conversion and down-conversion module;

[0084] S320. Synchronize the historical original signal and the historical feedback signal to obtain the synchronized historical original signal and the synchronized historical feedback signal;

[0085] S330. The modeler determines the power amplifier model to be established based on the synchronized historical original signal, the synchronized historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model;

[0086] S340. The modeler establishes the power amplifier model based on the model parameters; and determines the predistortion model corresponding to the predistorter based on the power amplifier model and the historical original signal;

[0087] S350. The predistorter performs predistortion processing on the original signal to be distorted using the predistortion model, and inputs the predistorted signal to be amplified obtained by the processing into the power amplifier;

[0088] S360. The power amplifier amplifies the predistorted signal to be amplified output by the predistorter.

[0089] In some examples, after obtaining the historical original signal and the historical feedback signal, since there may be an out-of-sync problem between the historical original signal and the historical feedback signal, therefore, in order to improve the accuracy of modeling the power amplifier model, the historical original signal and the historical feedback signal can be synchronized first.

[0090] In still other examples, the signal synchronization technology in the prior art can be used to synchronize the historical original signal and the historical feedback signal. Details are not described here again.

[0091] After synchronizing the historical original signal and the historical feedback signal, the synchronized historical original signal and the synchronized historical feedback signal can be obtained. Therefore, the modeler can determine the model parameters of the preset band-limited predistortion system model based on the synchronized historical original signal, the synchronized historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model, and then can use the model parameters of the preset band-limited predistortion system model as the model parameters of the power amplifier model to be established. Furthermore, the power amplifier model can be established based on the model parameters of the power amplifier model to be established.

[0092] It can be understood that steps S310, S340 to S360 in the embodiments of the present invention are the same as or similar to steps S210, S230 to S250 in the first implementation manner, and details are not described here again.

[0093] In Figure 2 Based on the signal processing method for a band-limited predistortion system shown, the embodiments of the present invention also provide a possible implementation manner. As Figure 4 shown, it is a flowchart of a third implementation manner of the signal processing method for a band-limited predistortion system according to the embodiments of the present invention. The method may include:

[0094] S401. The modeler obtains the historical original signal input into the digital-to-analog converter, the historical feedback signal output by the analog-to-digital conversion and down-conversion module, the baseband response of the filter, and the total order of the filter. The historical feedback signal is the signal output after the historical original signal passes through the digital-to-analog conversion and up-conversion module, the power amplifier, the coupler, the filter, and the analog-to-digital conversion and down-conversion module;

[0095] S402. The modeler obtains the model parameters of the preset band-limited predistortion system model and the initial values, where the initial values are pre-set values;

[0096] S403. Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameters of the preset band-limited predistortion system model and the initial values, through the preset band-limited predistortion system model, calculate the model parameter r 1l , r 2l and r 3l of the iterative values;

[0097] S404. Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameter r 1l , r 2l and r 3l , through the preset band-limited predistortion system model, calculate the model parameter and of the iterative values;

[0098] S405. Determine whether the iterative values of the model parameters r 1l , r 2l , r 3l , and of the preset band-limited predistortion system model reach the preset output condition. If so, execute step S406; otherwise, execute step S407;

[0099] S406. Use the iterative values of the model parameters r 1l , r 2l , r 3l , and of the preset band-limited predistortion system model as the model parameters of the power amplifier model to be established; and execute step S408;

[0100] S407. Use the model parameters and The iterative value of and the initial value of, and execute step S404;

[0101] In some examples, the above preset band - limited predistortion system model is the following formula:

[0102]

[0103] where, is the feedback signal, w(p) is the base - band response of the filter, P is the total order of the filter, L a , L b and L c are respectively the preset memory depth parameters, K a , K b and K c are respectively the preset orders, M b is the preset delay depth, M c is the preset lead depth; x(n - l1 - p) is the (l1 + p) - th time - delayed signal of the original signal x(n), x(n - l2 - p) is the (l2 + p) - th time - delayed signal of the original signal x(n), x(n - l2 - m2 - p) is the (l2 + m2 + p) - th time - delayed signal of the original signal x(n), x(n - l3 - p) is the (l3 + p) - th time - delayed signal of the original signal x(n), x(n - l3 + m3 - p) is the (l3 - m3 + p) - th time - delayed signal of the original signal x(n), r 1l , r 2l , r 3l , and are the model parameters of the preset band - limited predistortion system model;

[0104] where, the L a , L b and L c are all memory depth parameters of the preset band - limited predistortion system model and the power amplifier model to be established, K a , K b and K c are all orders of the preset band - limited predistortion system model and the power amplifier model to be established, M b is the delay depth of the preset band - limited predistortion system model and the power amplifier model to be established, M c is the lead depth of the preset band - limited predistortion system model and the power amplifier model to be established.

[0105] Therefore, when determining the model parameters of the power amplifier model to be established based on the historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and preset band-limited predistortion system model, an iterative method can be used to calculate the model parameters.

[0106] Specifically, the initial values of and in the model parameters can be set first, and then based on the initial values of and in the model parameters, historical original signal, historical feedback signal, baseband response of the filter, total order of the filter, and preset band-limited predistortion system model, the iterative values of r 1l , r 2l and r 3l in the model parameters can be calculated.

[0107] In some examples, the above base function formula can be abbreviated as the following formula:

[0108]

[0109] Where:

[0110]

[0111]

[0112]

[0113] Furthermore, the above base function formula can be further abbreviated as the following matrix form:

[0114]

[0115] Therefore, R can be expressed as: Where:

[0116]

[0117]

[0118] Where T represents transpose and H represents conjugate transpose.

[0119] And since R = [r 11 , r 12 ,..., r 21 , r 22 ,..., r 31 , r 32 ...] T , therefore, the r 1l , r 2l and r3l Iterative values

[0120] In some examples, the r in the model parameters can be calculated by the least squares method 1l , r 2l and r 3l Iterative values

[0121] In some examples, the above basis function formula can also be abbreviated as the following formula:

[0122]

[0123] where

[0124]

[0125]

[0126]

[0127] Furthermore, the above basis function formula can be further abbreviated as the following matrix form:

[0128]

[0129] Therefore, T can be expressed as: where:

[0130]

[0131] And since T = [a1,..., b 11 ,..., c 11 ,...] T , thus, the and Iterative values in the model parameters can be obtained

[0132] In some examples, the and Iterative values in the model parameters can be calculated by the least squares method

[0133] After obtaining the iterative values of the model parameters r 1l , r 2l , r 3l , and of the preset band-limited predistortion system model, it can be determined whether the iterative values of the model parameters reach the preset output condition. Among them, the preset output condition can be the preset number of iterations

[0134] When the iterative values of the model parameters do not reach the preset output condition, the model parameters of the preset band-limited predistortion system model can be and The iterative values of are used as the model parameters of the preset band-limited predistortion system model and The initial values of, and perform step S340 to continue the iterative calculation.

[0135] When the iterative value of the model parameter reaches the preset output condition, the model parameters r 1l , r 2l , r 3l , and The iterative values of are used as the model parameters of the power amplifier model to be established, so that the modeler can establish a power amplifier model based on the model parameters of the power amplifier model to be established;

[0136] S408, the modeler establishes a power amplifier model based on the model parameters of the power amplifier model to be established; and determines the predistortion model corresponding to the predistorter based on the power amplifier model and the historical original signal;

[0137] S409, the predistorter performs predistortion processing on the original signal using the predistortion model and inputs the processed predistorted signal to be amplified into the power amplifier;

[0138] S410, the power amplifier amplifies the predistorted signal to be amplified output by the predistorter.

[0139] In some examples, the power amplifier model to be established is the following formula:

[0140]

[0141] Wherein, is the full-band signal corresponding to the original signal output by the power amplifier, x(n - l1) is the l1-th time-delayed signal of the original signal x(n), x(n - l2) is the l2-th time-delayed signal of the original signal x(n), x(n - l2 - m2) is the (l2 + m2)-th time-delayed signal of the original signal x(n), x(n - l3) is the l3-th time-delayed signal of the original signal x(n), and x(n - l3 + m3) is the (l3 - m3)-th time-delayed signal of the original signal x(n).

[0142] Therefore, when establishing a power amplifier model based on the model parameters, the calculated values of the model parameters of the power amplifier model to be established can be used to replace the parameters in the formula of the power amplifier model to be established above, so as to establish a power amplifier model.

[0143] It can be understood that steps S401, S408, and S409 in the embodiments of the present invention are the same as or similar to steps S210, S230, and S240 in the first implementation manner of the embodiments of the present invention, and will not be elaborated here.

[0144] Corresponding to the above method embodiments, an embodiment of the present invention further provides a band-limited predistortion system. The structure of the band-limited predistortion system is the same as Figure 1 the structure of the band-limited predistortion system shown, as Figure 1 shown, is a schematic structural diagram of a band-limited predistortion system according to an embodiment of the present invention. The band-limited predistortion system may include: a predistorter 110, a digital-to-analog conversion and up-conversion module 120, a power amplifier 130, a coupler 140, a filter 150, an analog-to-digital conversion and down-conversion module 160, and a modeler 170; the predistorter 110, the digital-to-analog conversion and up-conversion module 120, the power amplifier 130, the coupler 140, the filter 150, the analog-to-digital conversion and down-conversion module 160, and the modeler 170 are connected in sequence; the modeler 170 is further connected to the predistorter 110;

[0145] The modeler 170 is configured to: obtain the historical original signal input to the digital-to-analog conversion and up-conversion module 120, the historical feedback signal output by the analog-to-digital conversion and down-conversion module 160, the baseband response of the filter 150, and the total order of the filter 150, where the historical feedback signal is the signal output after the historical original signal passes through the digital-to-analog conversion and up-conversion module 120, the power amplifier 130, the coupler 140, the filter 150, and the analog-to-digital conversion and down-conversion module 160;

[0146] The modeler 170 is further configured to: determine the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter 150, the total order of the filter 150, and a preset band-limited predistortion system model;

[0147] The modeler 170 is further configured to: establish a power amplifier model based on the model parameters; and determine the predistortion model corresponding to the predistorter 110 based on the power amplifier model and the historical original signal;

[0148] The predistorter 110 is configured to perform predistortion processing on the to-be-distorted original signal using the predistortion model, and input the pre-distorted signal to be amplified obtained by the processing into the power amplifier 130;

[0149] The power amplifier 130 is configured to perform amplification processing on the pre-distorted signal to be amplified output by the predistorter 110.

[0150] A band-limited predistortion system provided by an embodiment of the present invention. The modeler can first obtain the historical original signal input into the digital-to-analog conversion and up-conversion module, the historical feedback signal output by the analog-to-digital conversion and down-conversion module, the baseband response of the filter, and the total order of the filter. Then, based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model, the modeler determines the model parameters of the preset band-limited predistortion system model. In this way, the model parameters of the preset band-limited predistortion system model can be determined as the model parameters of the power amplifier model to be established. Thus, a power amplifier model can be established based on the model parameters of the power amplifier model to be established. After the power amplifier model is established, the full-band signal corresponding to the historical original signal can be obtained through the power amplifier model. Furthermore, a predistortion model can be constructed according to the historical original signal and the calculated full-band signal. Finally, the signal obtained by passing the signal to be distorted through the predistorter and the power amplifier is linear with the signal to be distorted itself. Since in the embodiment of the present invention, when establishing the power amplifier model, the influence of the filter order on the model memory depth is considered, and the coefficients related to the model memory depth are calculated separately, the process of solving the power amplifier model is not easily interfered by the filter. Therefore, the power amplifier model obtained by modeling is more accurate. Furthermore, when using the power amplifier model and the predistortion model to perform predistortion and amplification processing on the signal, the linearization effect is better. And when the filter bandwidth is narrow, a more accurate power amplifier model can be obtained than the traditional method. Furthermore, the sampling rate of the necessary analog-to-digital converter in the feedback loop can be reduced, saving engineering costs.

[0151] In some examples, the modeler 170 is further configured to:

[0152] Before determining the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter 150, the total order of the filter 150, and the preset band-limited predistortion system model, synchronize the historical original signal and the historical feedback signal to obtain the synchronized historical original signal and the synchronized historical feedback signal;

[0153] The modeler 170 is further configured to:

[0154] Based on the synchronized historical original signal, the synchronized historical feedback signal, the baseband response of the filter 150, the total order of the filter 150, and the preset band-limited predistortion system model, determine the model parameters of the power amplifier model to be established.

[0155] In some examples, the preset band-limited predistortion system model is the following formula:

[0156]

[0157] Among them, is the feedback signal, w(p) is the baseband response of filter 150, P is the total order of filter 150, L a , L b and L c are respectively the preset memory depth parameters, K a , K b and K c are respectively the preset orders, M b is the preset delay depth, M c is the preset leading depth; x(n - l1 - p) is the (l1 + p)-th time-delayed signal of the original signal x(n), x(n - l2 - p) is the (l2 + p)-th time-delayed signal of the original signal x(n), x(n - l2 - m2 - p) is the (l2 + m2 + p)-th time-delayed signal of the original signal x(n), x(n - l3 - p) is the (l3 + p)-th time-delayed signal of the original signal x(n), x(n - l3 + m3 - p) is the (l3 - m3 + p)-th time-delayed signal of the original signal x(n), r 1l , r 2l , r 3l , and are the model parameters of the preset band-limited predistortion system model;

[0158] The power amplifier model to be established is as follows:

[0159]

[0160] Among them, is the full-band signal corresponding to the original signal output by the power amplifier 130, x(n - l1) is the l1-th time-delayed signal of the original signal x(n), x(n - l2) is the l2-th time-delayed signal of the original signal x(n), x(n - l2 - m2) is the (l2 + m2)-th time-delayed signal of the original signal x(n), x(n - l3) is the l3-th time-delayed signal of the original signal x(n), x(n - l3 + m3) is the (l3 - m3)-th time-delayed signal of the original signal x(n).

[0161] In some examples, the modeler 170 is specifically used for:

[0162] Obtain the initial values of the model parameters of the preset band-limited predistortion system model and , where the initial values are preset values;

[0163] Based on the historical original signal, historical feedback signal, baseband response of filter 150, total order of filter 150, and model parameters of the preset band-limited predistortion system model and the initial values, calculate the model parameters r of the preset band-limited predistortion system model through the preset band-limited predistortion system model 1l , r 2l and r 3l iteration values;

[0164] Based on the historical original signal, historical feedback signal, baseband response of filter 150, total order of filter 150, and model parameter r of the preset band-limited predistortion system model 1l , r 2l , r 3l , calculate the model parameters of the preset band-limited predistortion system model through the preset band-limited predistortion system model and iteration values;

[0165] When the iteration values of the model parameters r 1l , r 2l , r 3l , and reach the preset output conditions, take the iteration values of the model parameters r 1l , r 2l , r 3l , and as the model parameters of the power amplifier model to be established;

[0166] Otherwise, take the iteration values of the model parameters and as the initial values of the model parameters and of the preset band-limited predistortion system model, and execute the step of calculating the iteration values of the model parameters r and of the preset band-limited predistortion system model through the preset band-limited predistortion system model based on the historical original signal, historical feedback signal, baseband response of filter 150, total order of filter 150, and the initial values of the model parameters 1l , r 2l and r 3l ;

[0167] In some examples, the modeler 170 is specifically used for:

[0168] Based on the historical original signal, historical feedback signal, baseband response of filter 150, total order of filter 150, and the model parameters and The initial value, by presetting a band-limited predistortion system model and using the least squares method to calculate the model parameters r of the preset band-limited predistortion system model 1l , r 2l and r 3l of the iterative value;

[0169] Based on the historical original signal, the historical feedback signal, the baseband response of the filter 150, the total order of the filter 150, and the model parameter r of the preset band-limited predistortion system model 1l , r 2l , r 3l , by presetting a band-limited predistortion system model and using the least squares method to calculate the model parameters and of the iterative value.

[0170] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present invention are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that the computer can access or a data storage device such as a server or data center that includes one or more integrated available media. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (SSD)).

[0171] It should be noted that in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variation thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0172] Each embodiment in this specification is described in a related manner. For the same or similar parts among the embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and reference can be made to the relevant part of the method embodiment for the related content.

[0173] The above are only the preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are included within the protection scope of the present invention.

Claims

1. A signal processing method for a band-limited predistortion system, characterized in that, Applied to a band-limited predistortion system, the band-limited predistortion system includes: a predistorter, a digital-to-analog conversion and up-conversion module, a power amplifier, a coupler, a filter, an analog-to-digital conversion and down-conversion module, and a modeler; the predistorter, the digital-to-analog conversion and up-conversion module, the power amplifier, the coupler, the filter, the analog-to-digital conversion and down-conversion module, and the modeler are connected in sequence; the modeler is connected to the predistorter; the method includes: The modeler obtains the historical original signal input into the digital-to-analog conversion and up-conversion module, the historical feedback signal output by the analog-to-digital conversion and down-conversion module, the baseband response of the filter, and the total order of the filter, where the historical feedback signal is the signal output after the historical original signal passes through the digital-to-analog conversion and up-conversion module, the power amplifier, the coupler, the filter, and the analog-to-digital conversion and down-conversion module; The modeler determines the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and a preset band-limited predistortion system model; The modeler establishes the power amplifier model based on the model parameters; and determines the predistortion model corresponding to the predistorter based on the power amplifier model and the historical original signal; The predistorter performs predistortion processing on the original signal to be distorted using the predistortion model, and inputs the pre-distorted signal to be amplified obtained by the processing into the power amplifier; The power amplifier amplifies the pre-distorted signal to be amplified output by the predistorter; The preset band-limited predistortion system model is the following formula: ； Among them, the is a feedback signal, the is the baseband response of the filter, the is the total order of the filter, the , the and the are respectively pre-set memory depth parameters, the , and are respectively pre-set orders, the is the pre-set delay depth, the is the pre-set leading depth; the is the th time-delay signal of the original signal , the is the th time-delay signal of the original signal , the is the th time-delay signal of the original signal , the is the th time-delay signal of the original signal , the is the th time-delay signal of the original signal , the , , , , and are the model parameters of the preset band-limited predistortion system model; The power amplifier model to be established is the following formula: ； Among them, the is the full-band signal corresponding to the original signal output by the power amplifier, and the is the th time-delay signal of the original signal, the is the th time-delay signal of the original signal, the is the th time-delay signal of the original signal, the is the th time-delay signal of the original signal, the is the th time-delay signal of the original signal.

2. The method according to claim 1, wherein Before determining the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model, the method further includes: Synchronize the historical original signal and the historical feedback signal to obtain the synchronized historical original signal and the synchronized historical feedback signal; Determining the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model includes: Determining the model parameters of the power amplifier model to be established based on the synchronized historical original signal, the synchronized historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model.

3. The method according to claim 1, wherein Determining the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model includes: Obtain the model parameters of the preset band-limited predistortion system model , and initial values, where the initial values are pre-set values; Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameters of the preset band-limited predistortion system model , and the initial values of, calculate the iterative values of the model parameters , , and of the preset band-limited predistortion system model through the preset band-limited predistortion system model;​​​ Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameters of the preset band-limited predistortion system model , , , calculate the model parameters of the preset band-limited predistortion system model through the preset band-limited predistortion system model , and iteration values; When the iterative values of , , , , and reach the preset output conditions, the iterative values of the model parameters , , , , and of the preset band-limited predistortion system model are used as the model parameters of the power amplifier model to be established; Otherwise, use the iterative values of the model parameters of the preset band-limited predistortion system model , and as the model parameters of the preset band-limited predistortion system model , and as the initial values, and execute the step of calculating the iterative values of the model parameters of the preset band-limited predistortion system model , and through the preset band-limited predistortion system model based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the initial values of the model parameters of the preset band-limited predistortion system model , and .

4. The method according to claim 3, wherein Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameters of the preset band-limited predistortion system model , and the initial values of, calculate the model parameters of the preset band-limited predistortion system model through the preset band-limited predistortion system model , and the iterative values of, including: Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameters of the preset band-limited predistortion system model , and the initial values of, through the preset band-limited predistortion system model, and using the least squares method to calculate the model parameters of the preset band-limited predistortion system model , and the iterative values of; Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameters of the preset band-limited predistortion system model , , , calculate the model parameters of the preset band-limited predistortion system model through the preset band-limited predistortion system model , and iteration values of, including: Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter and the model parameters of the preset band-limited predistortion system model , , , by using the preset band-limited predistortion system model and using the least squares method to calculate the model parameters of the preset band-limited predistortion system model , and The iteration value of .

5. A band-limited predistortion system, characterized in that, The band-limited predistortion system includes: a predistorter, a digital-to-analog conversion and up-conversion module, a power amplifier, a coupler, a filter, an analog-to-digital conversion and down-conversion module, and a modeler; the predistorter, the digital-to-analog conversion and up-conversion module, the power amplifier, the coupler, the filter, the analog-to-digital conversion and down-conversion module, and the modeler are connected in sequence; the modeler is connected to the predistorter; The modeler is configured to: obtain the historical original signal input into the digital-to-analog conversion and up-conversion module, the historical feedback signal output by the analog-to-digital conversion and down-conversion module, the baseband response of the filter, and the total order of the filter, where the historical feedback signal is the signal output after the historical original signal passes through the digital-to-analog conversion and up-conversion module, the power amplifier, the coupler, the filter, and the analog-to-digital conversion and down-conversion module; The modeler is further configured to: determine the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and a preset band-limited predistortion system model; The modeler is further configured to: establish the power amplifier model based on the model parameters; and determine the predistortion model corresponding to the predistorter based on the power amplifier model and the historical original signal; The predistorter is configured to perform predistortion processing on the original signal to be distorted by using the predistortion model, and input the pre-distorted signal to be amplified obtained by the processing into the power amplifier; The power amplifier is configured to perform amplification processing on the pre-distorted signal to be amplified output by the predistorter; The preset band-limited predistortion system model is the following formula: ； Among them, the is a feedback signal, the is the baseband response of the filter, the is the total order of the filter, the , the and the are respectively pre-set memory depth parameters, the , and are respectively pre-set orders, the is the pre-set delay depth, the is the pre-set lead depth; the is the original signal 's th time-delayed signal, the is the original signal 's th time-delayed signal, the is the original signal 's th time-delayed signal, the is the original signal 's th time-delayed signal, the is the original signal 's th time-delayed signal, the , , , , and are the model parameters of the preset band-limited predistortion system model; The power amplifier model to be established is the following formula: ； Among them, the is a full-band signal corresponding to the original signal output by the power amplifier, The original signal No. A time-delayed signal, the The original signal No. A time-delayed signal, the The original signal No. A time-delayed signal, the The original signal No. A time-delayed signal, the The original signal No. A time-delayed signal.

6. The system according to claim 5, wherein The modeler is further configured to: Before determining the model parameters of the power amplifier model to be established based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model, synchronize the historical original signal and the historical feedback signal to obtain the synchronized historical original signal and the synchronized historical feedback signal; The modeler is further configured to: Determine the model parameters of the power amplifier model to be established based on the synchronized historical original signal, the synchronized historical feedback signal, the baseband response of the filter, the total order of the filter, and the preset band-limited predistortion system model.

7. The system according to claim 5, characterized in that, Specifically, the modeler is configured to: Obtain the model parameters of the preset band-limited predistortion system model , and initial values, where the initial values are pre-set values; Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameters of the preset band-limited predistortion system model , and the initial values of, calculate the model parameters of the preset band-limited predistortion system model , and the iterative values of; Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter and the model parameters of the preset band-limited predistortion system model , , , calculating the model parameters of the preset band-limited predistortion system model through the preset band-limited predistortion system model , and The iteration value of Among the model parameters of the preset band-limited predistortion system model , , , , and , when the iteration values reach the preset output conditions, the iteration values of the model parameters , , , , and of the preset band-limited predistortion system model are used as the model parameters of the power amplifier model to be established; Otherwise, use the iterative values of the model parameters of the preset band-limited predistortion system model , and as the model parameters of the preset band-limited predistortion system model , and as the initial values, and perform the step of calculating the iterative values of the model parameters of the preset band-limited predistortion system model , and based on the initial values of the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameters of the preset band-limited predistortion system model , and through the preset band-limited predistortion system model.

8. The system according to claim 7, wherein Specifically, the modeler is configured to: Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameters of the preset band-limited predistortion system model , and the initial values of, through the preset band-limited predistortion system model, and using the least squares method to calculate the model parameters of the preset band-limited predistortion system model , and the iterative values of; Based on the historical original signal, the historical feedback signal, the baseband response of the filter, the total order of the filter, and the model parameters of the preset band-limited predistortion system model , , , calculate the model parameters of the preset band-limited predistortion system model through the preset band-limited predistortion system model and by using the least squares method , and the iteration values of.

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