Digital predistortion method, storage medium and device capable of integrated correction of shortwave power amplifier frequency response

Abstract

The present invention aims to address the problem that when a shortwave transmitter uses digital predistortion technology to improve transmitter efficiency, the behavioral characteristics of different frequencies within the shortwave transmitter's operating bandwidth are different, resulting in reduced communication system transmission efficiency, adjacent channel interference, increased receiver bit error rate, and impact on the stability of the entire shortwave transmitter. The present invention provides a digital predistortion method, storage medium, and device that can integrate and correct the frequency response of a shortwave power amplifier. The present invention divides the shortwave frequency into K frequency intervals, performs amplitude indexing on the frequency points within each frequency interval, obtains adaptive predistortion coefficients and a lookup table, then divides the shortwave frequency into M frequency intervals, performs frequency indexing on all frequency points according to the gain compensation table corresponding to each frequency interval, and performs real-time integration and compensation of the gain compensation values ​​of the corresponding frequency points with the amplitude-compensated predistortion signal, thereby obtaining a digital predistortion signal with a smoother frequency response of the shortwave power amplifier.

Description

Technical Field

[0001] The present invention relates to the technical field of digital predistortion, and in particular to a digital predistortion method, storage medium and device capable of integrating and correcting the frequency response of a shortwave power amplifier. Background Art

[0002] The development of digital mobile communication technology has placed increasingly stringent demands on the performance of base station power amplifiers, requiring them to achieve high efficiency while meeting high linearity requirements. To achieve this, amplifiers must be both linear and efficient, placing a demand on linearization of the RF amplifier or RF system.

[0003] Radio frequency waves between 1.6MHz and 30MHz are commonly referred to as the shortwave band. Using shortwave frequencies for worldwide one-way broadcasting is often referred to as shortwave broadcasting, and radios capable of receiving a specific frequency band are called shortwave radio stations. Because shortwave communications rely primarily on reflection and refraction between the ionosphere and the ground, they can travel great distances, day or night. With the continuous advancement of computers, microelectronics, and wireless communication technologies, shortwave communication technology has made breakthroughs, playing a more important and extensive role in emergency communications, disaster relief communications, and, in particular, in unified communications and command for land, sea, and air forces, as required by the military.

[0004] Currently, shortwave radio stations are becoming increasingly digital, and their operating frequency bands are no longer limited to the original shortwave frequency band, thus showing multi-band and multi-channel characteristics. The digitalization of shortwave radio stations has put forward increasingly higher requirements on the performance of shortwave power amplifiers, that is, to achieve higher efficiency while meeting higher linearity requirements.

[0005] To achieve this requirement, amplifiers must be both linear and efficient, employing various methods to achieve both high efficiency and linearity. A key step in the development of power amplifier linearization technology is the emergence of predistortion. Initially applied to the RF portion of analog communication systems, advances in digital signal processing have enabled its implementation in the digital domain, resulting in digital predistortion (DPD). Predistortion not only improves transmitter efficiency, reduces costs, and reduces size, but also effectively enhances transmitter linearity, improving system performance and communication quality. This holds significant practical significance for the development and implementation of future high-efficiency shortwave radios. To facilitate implementation, DPD systems employ a lookup table (LUT) approach. In this approach, the predistortion LUT extraction structure continuously iteratively modifies the output predistortion LUT for use by the DPD system.

[0006] Digital pre-distortion (DPD) technology is based on processing baseband signals, which correspond to the RF signal envelope. In theory, a power amplifier should have identical frequency characteristics—that is, identical gain and nonlinearity—at all frequencies within its operating bandwidth. However, practical power amplifiers cannot achieve this, and their behavior varies at different frequencies. Therefore, a pre-distortion model established by sampling signals at one RF frequency may not be applicable at other frequencies.

[0007] Building on the above, we further consider that in practical shortwave transmitters, when the power amplifier is at high efficiency, the system often operates in a nonlinear state. This not only reduces the transmission efficiency of the communication system but also generates adjacent channel interference, significantly increasing the receiver's bit error rate. According to GJB regulations and the requirements of the entire device in actual applications, the power amplifier gain flatness is generally required to be ±1dB, meaning that the maximum frequency response tolerance within the shortwave effective frequency range (2-30MHz) should not exceed 2dB. However, due to the generally high transmit power of shortwave amplifiers, for example, a 1dB fluctuation in a 200W shortwave amplifier will result in a 50W transmit power change, thus affecting the stability of the shortwave transmitter. Therefore, improving the linearity and flatness of the power amplifier is crucial for improving the stability of the amplifier output power, the effectiveness of the transmitter service system, and the communication system. Summary of the Invention

[0008] The purpose of the present invention is to solve the problem that shortwave transmitters currently use digital predistortion technology to improve transmitter efficiency, wherein the behavioral characteristics of different frequency points within the operating bandwidth of the shortwave transmitter are different, resulting in a decrease in the transmission efficiency of the communication system, the generation of adjacent channel interference, an increase in the bit error rate of the receiver, and an impact on the stability of the shortwave transmitter as a whole. A digital predistortion method, storage medium and device that can be integrated to correct the frequency response of a shortwave power amplifier are provided.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is:

[0010] A digital predistortion method capable of integrating and correcting the frequency response of a shortwave power amplifier is characterized in that it comprises the following steps:

[0011] 1) Create LUT lookup table and gain compensation lookup table

[0012] 1.1) Based on the principle of effectiveness of digital baseband signal predistortion at a given frequency point, the shortwave frequency is divided into K continuous frequency intervals. The digital predistortion system operates in a certain frequency interval, obtains output power data for that frequency interval, and feeds it back for predistortion processing to obtain a lookup table (LUT) for that frequency interval. Repeat the above steps to obtain a LUT for K frequency intervals; the K continuous frequency intervals are f_1, f_2, ..., f_K.

[0013] 1.2) While establishing a LUT lookup table for K frequency intervals in the digital pre-distortion system, the shortwave frequency is divided into M continuous frequency intervals to obtain a gain compensation lookup table for the M frequency intervals; the M continuous frequency intervals are F_1, F_2, ..., F_M;

[0014] The M frequency intervals are divided into shortwave frequencies based on the principle of being able to compensate for the unevenness of the digital baseband signal in real time under the communication state;

[0015] 2) Digital pre-distortion processing through the pre-distortion channel

[0016] 2.1) When a digital baseband signal X(n) at a certain frequency arrives, the digital predistortion system multiplies the LUT index result by the input signal X(n) at that moment to obtain the amplitude predistortion signal X_DPD(n). The system then multiplies the gain compensation value obtained by indexing the gain compensation lookup table at a certain frequency by the amplitude predistortion signal X_DPD(n) to obtain the corrected predistortion signal Z(n).

[0017] 2.2) Based on the relationship between the predistortion signal Z(n) output by the digital predistortion system and the input signal X(n) at the current moment, the LUT lookup table and the gain compensation lookup table are updated in real time, and predistortion processing of the input signal at the next moment is continued until the digital predistortion processing of the digital baseband signal is completed.

[0018] Furthermore, step 2.1) is specifically as follows:

[0019] 2.1.1) After the power calculation of the digital baseband signal X(n) corresponding to frequency point i, the corresponding amplitude is obtained. The amplitude is used as the address of the LUT of frequency point i, and the LUT lookup table LUT(1) to LUT(N) corresponding to the frequency interval f_i where frequency point i is located is indexed to obtain the corresponding LUT value, and the LUT value is multiplied by the digital baseband signal X(n) at the current moment to obtain the amplitude predistortion signal X_DPD(n);

[0020] 2.1.2) Look up the gain compensation Gain(i) corresponding to the frequency point i in the gain compensation lookup table corresponding to the frequency interval F_i where the frequency point i is located, and multiply the gain compensation by the amplitude predistortion signal X_DPD(n) to obtain the corrected predistortion signal Z(n).

[0021] Furthermore, in step 2.1.1), N=128.

[0022] Furthermore, step 2.2) is specifically as follows:

[0023] 2.2.1) Calculate the normalized mean square error (NMSE) between the current digital baseband input signal and the predistortion output signal. dB ;

[0024] 2.2.2) Determine the normalized mean square error NMSE dB Is it greater than the preset target value?

[0025] If yes, the predistortion parameters are calculated using the least squares method, and the predistortion parameters in the corresponding LUT lookup table are replaced with the parameters, and the process returns to step 2) for predistortion processing;

[0026] Otherwise, the predistortion processing of the current digital baseband input signal is terminated, and the predistortion processing of the next input signal continues to use the current lookup table until the digital predistortion processing of the digital baseband signal is completed.

[0027] Furthermore, in step 1.1), the frequency intervals of the K consecutive frequency intervals are the same;

[0028] In step 1.2), the frequency intervals of the M consecutive frequency intervals are the same.

[0029] Furthermore, in step 1.1), the frequency interval of the K consecutive frequency intervals is 100 KHz;

[0030] In step 1.2), the frequency interval of the M consecutive frequency intervals is 1 MHz.

[0031] The present invention also provides a computer storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the steps of the above-mentioned digital predistortion method capable of integrating and correcting the frequency response of a shortwave power amplifier.

[0032] The present invention also provides a computer device comprising a processor, a memory connected to the processor, and a computer program that can be run on the memory. The special feature of the computer device is that when the processor executes the computer program, the steps of the above-mentioned digital predistortion method that can integrate and correct the frequency response of a shortwave power amplifier are implemented.

[0033] Compared with the prior art, the present invention has the following beneficial technical effects:

[0034] 1. The digital predistortion method proposed in the present invention can integrate and correct the frequency response of a shortwave power amplifier, thereby improving the performance of the digital predistortion system and further improving the stability of the power amplifier output power, the effectiveness of the transmitter service system and the communication system.

[0035] 2. The digital predistortion method proposed in the present invention can integrate and correct the frequency response of a shortwave power amplifier. In an offline state, a segmented fitting method including but not limited to the least squares method is used to calibrate the frequency response of the power amplifier. In a communication state, the flatness is compensated in real time. The predistortion method of the present invention is used to obtain a digital predistortion signal of the shortwave power amplifier frequency response with smoother characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is the overall architecture diagram of the existing pre-distortion structure;

[0037] Figure 2 Extract schematics for existing predistortion tables;

[0038] Figure 3 An index structure diagram for an existing pre-distortion model table;

[0039] Figure 4 The LUT architecture diagram corresponding to the amplitude index of the pre-distortion table power calculation;

[0040] Figure 5 This is the measured frequency response diagram of a 125W shortwave power amplifier;

[0041] Figure 6 FIG. 1 is a diagram of a digital predistortion architecture capable of integrating and correcting the frequency response of a shortwave power amplifier according to an embodiment of the present invention. DETAILED DESCRIPTION

[0042] To make the objectives, advantages, and features of the present invention more apparent, the following describes in further detail a digital predistortion method, storage medium, and device for integrated correction of the frequency response of a shortwave power amplifier, as proposed by the present invention, in conjunction with the accompanying drawings and specific embodiments. Those skilled in the art should understand that these embodiments are merely intended to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0043] like Figure 1As shown, a pre-distortion structure in the prior art uses a lookup table (LUT) method. This form of pre-distortion works with the help of a LUT. The LUT searches according to the amplitude of the signal, or a certain function of the input amplitude, and then corrects the amplitude and phase of the signal applied to the input of the power amplifier to offset its distortion. The pre-distortion system structure includes two channels: a data training loop channel and a pre-distortion channel. The data training channel is a loop structure, and its core part is the pre-distortion algorithm module. This module processes the feedback output signal after the power amplifier (the signal after the power amplifier output coupling) and the original input signal to obtain the distortion characteristics of the power amplifier, and then obtains the LUT parameters of the power amplifier distortion inverse characteristics. When the power amplifier characteristics change over time or with changes in the external environment, the pre-distortion inverse characteristic LUT parameters can be updated through an adaptive pre-distortion algorithm.

[0044] like Figure 2 As shown in FIG, it is a schematic diagram of a pre-distortion parameter extraction method of the prior art. Wherein, X is the input signal and Y is the feedback signal. First, the output power is determined according to the demand. During the first operation, the system is directly connected and all LUT parameters are defined as "1". LUT(X)=X. After the signal passes through the power amplifier, the first set of output data is obtained. The feedback is pre-distorted. The LUT parameters are obtained by solving min|LUT(Y)-LUT(X)|. Then, the LUT parameters are continuously modified in the iterative process until the output signal Y obtains a satisfactory effect. The LUT parameters at this time are extracted as the pre-distortion LUT under this output power and are provided to the system in the form of LUT(1)~LUT(N). N can be selected according to the system resources and performance requirements. Here, 128 is selected.

[0045] like Figure 3 Figure 1 shows a table index structure for a conventional predistortion model. The LUT parameters are calculated by performing power calculations on the input data to obtain the corresponding table index address |x(n)|. This LUT parameter, LUT(|x(n)|), is then used to correct the amplitude and phase of the signal X(n) applied to the power amplifier input to obtain the post-predistortion DPD(x(n)).

[0046] like Figure 4 Figure 2 shows the LUT architecture corresponding to the amplitude index in the pre-distortion table power calculation. Digital pre-distortion systems require power amplifier modeling and pre-distortion coefficient estimation. To ensure accuracy in both modeling and coefficient calculation, floating-point operations are employed. Directly performing floating-point operations in hardware within an FPGA would waste significant resources and reduce performance. Therefore, current pre-distortion platforms typically offload this functionality to ARM processors or DSPs, resulting in the ARM+FPGA and DSP+FPGA architectures.

[0047] As mentioned in the background technology, the pre-distortion model established by collecting signals at one RF frequency point is not necessarily applicable to other frequency points. The greater the difference in the carrier frequency of the RF signal, the worse the optimization effect of the pre-distortion. Therefore, it is necessary to establish a pre-distortion model for the power amplifier at different frequency points. After analyzing the frequency coverage of the pre-distortion linearity optimization effect of a single frequency point, while minimizing the use of hardware resources, the pre-distortion model is established in each frequency point interval (f_1~f_K) within the shortwave radio operating range of 1.6MHz~30.0MHz at a certain frequency interval to ensure the effectiveness of the pre-distortion effect at the set frequency point. The number of frequency points K here can be selected according to system resources and performance requirements. The frequency interval here is 100KHz.

[0048] The specific implementation process of the digital pre-distortion system is as follows: DPD initialization sets the I-channel parameters in the pre-distorter RAM table to 1 and the Q-channel parameters to 0. After the clock is enabled, the frequency value to be pre-distorted is determined. Frequency i=1 represents the first frequency (i=1, 2, 3...). At the same time, the enable signal of the corresponding frequency is input to enable the LUT parameters of the corresponding frequency.

[0049] A further consideration is that the more consistent the PA's characteristics are within its amplification frequency band, the wider the optimized frequency range for predistortion. Therefore, during the PA design process, its gain fluctuation should be minimized to ensure a stable performance within its operating frequency band. The maximum frequency response tolerance for shortwave radios operating within the 1.6MHz to 30.0MHz range is no more than 2dB. Figure 5 The figure shows the measured frequency response of a 125W shortwave power amplifier. Since shortwave transmitters have a specific frequency response, the power amplifier output needs to be further calibrated based on the frequency response curve within the shortwave radio's operating frequency range to ensure real-time compensation for in-band non-flatness during communication.

[0050] To reduce the resources consumed by actual measurements, the present invention uses offline fitting methods, including but not limited to the least squares method, to obtain more detailed power amplifier output power calibration parameters (this is to meet the need for more precise gain compensation values ​​in certain scenarios). This allows for real-time compensation of in-band non-flatness during communication. The number M of power amplifier output power calibration parameters can be selected based on system resources and performance requirements, with a frequency interval of 1 MHz in this example.

[0051] To ensure that the correction data in the measurement state is effective for each driver every time it is turned on, the correction function data is stored in ROM. When the system is turned on, the data space specified by ROM is first called to configure the gain compensation value (frequency response correction coefficient) and obtain the gain compensation table to ensure normal operation. The present invention adopts a two-dimensional index digital predistortion system structure with frequency index and amplitude index of the predistortion table, and further integrates the correction of the shortwave power amplifier frequency response on this basis. Figure 6 This is a diagram of the digital predistortion architecture for integrating and correcting the frequency response of a shortwave power amplifier proposed by the present invention.

[0052] The digital predistortion method for integrating and correcting the frequency response of a shortwave power amplifier proposed in the present invention specifically includes the following steps:

[0053] 1) Create LUT lookup table and gain compensation lookup table

[0054] 1.1) Based on the principle of effectiveness of digital baseband signal predistortion at the set frequency point, the shortwave frequency is divided into K continuous frequency intervals (f_1, f_2, ..., f_K). The digital predistortion system operates in a certain frequency interval, obtains the output power data of this frequency interval, and feeds it back for predistortion processing to obtain a lookup table (LUT) for this frequency interval. Repeat the above steps to obtain the LUT lookup table for K frequency intervals.

[0055] There are N LUT lookup tables corresponding to each frequency interval, namely LUT (1) to LUT (N). N can be selected based on system resources and performance requirements, and is 128 here.

[0056] For example: The operating range of a shortwave radio station is 1.6MHz to 30.0MHz, and the frequency interval can be 100KHz.

[0057] After the digital baseband signal is processed by the digital predistorter, a predistortion signal is obtained; the predistortion signal is converted into an analog signal by a digital-to-analog converter, and then amplified by a power amplifier to obtain an amplified analog signal; the amplified analog signal is coupled and attenuated by a post-attenuator, and then converted into a digital signal by an analog-to-digital converter and transmitted to the predistortion parameter extraction module; the predistortion parameter extraction module processes the collected digital signal and the predistortion signal to obtain the predistortion parameters, namely the LUT lookup table;

[0058] 1.2) While the digital pre-distortion system establishes a lookup table (LUT) for K frequency intervals, the shortwave frequency is divided into M continuous frequency intervals (F_1, F_2, ..., F_M), and a gain compensation lookup table for the M frequency intervals is obtained;

[0059] The M frequency intervals are divided into shortwave frequencies based on the principle of being able to compensate for the unevenness of the digital baseband signal in real time under the communication state;

[0060] Shortwave frequency division can specifically divide the working range of the digital baseband signal into the same frequency intervals.

[0061] 2) Digital pre-distortion processing through the pre-distortion channel

[0062] 2.1) When a digital baseband signal X(n) at a certain frequency arrives, the digital predistortion system multiplies the LUT index result by the input signal X(n) at that moment to obtain the amplitude predistortion signal X_DPD(n). The system then multiplies the gain compensation value obtained by indexing the gain compensation lookup table at a certain frequency by the amplitude predistortion signal X_DPD(n) to obtain the corrected predistortion signal Z(n).

[0063] 2.1.1) The digital baseband signal X(n) corresponding to frequency point i (1≤i≤K) is subjected to power calculation to obtain the corresponding amplitude. This amplitude is used as the address of the LUT for frequency point i. The LUT lookup table LUT(1) to LUT(N) corresponding to the frequency interval f_i where frequency point i is located is indexed to obtain the corresponding LUT value. This LUT value is then multiplied by the input signal X(n) at the current moment to obtain the amplitude predistortion signal X_DPD(n).

[0064] 2.1.2) In the gain compensation lookup table corresponding to the frequency interval f_i where the corresponding frequency point i is located, find the gain compensation Gain(i) corresponding to the interval where the digital baseband signal X(n) corresponding to the frequency point i (1≤i≤M) is located, and multiply the gain compensation by the amplitude predistortion signal X_DPD(n) to obtain the corrected predistortion signal Z(n).

[0065] 2.2) Based on the relationship between the predistortion signal Z(n) output by the digital predistortion system and the input signal X(n) at the current moment, the LUT lookup table and the gain compensation lookup table are updated in real time, and the predistortion processing of the input signal at the next moment is continued. Specifically:

[0066] 2.2.1. Calculate the normalized mean square error (NMSE) between the current input signal and the predistorted output signal. dB ;

[0067] 2.2.2. Determine the calculated normalized mean square error NMSE dB Is it greater than the preset target value?

[0068] If yes, the predistortion parameters are calculated using the least squares method, and the corresponding LUT lookup table is updated, and the process returns to step 2) for predistortion processing;

[0069] Otherwise, the current round of predistortion processing is terminated, and the predistortion processing of the next input signal continues to use the current lookup table until the digital predistortion processing of the digital baseband signal is completed.

[0070] The present invention performs frequency indexing on the digital baseband signal at the intermediate frequency point i, and can integrate and compensate the corresponding predistortion result and the corresponding gain compensation result in real time, thereby obtaining a digital predistortion signal with a more stable shortwave power amplifier frequency response.

[0071] All or part of the steps of the above-mentioned method embodiment can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment. The storage medium includes: ROM, RAM, disk or optical disk, etc. Various media that can store program codes.

[0072] Corresponding to the above method embodiment, the embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned external storage medium detection method are implemented.

[0073] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention.

Claims

1. A digital predistortion method for integrating and correcting the frequency response of a shortwave power amplifier comprises the following steps: 1) Create LUT lookup table and gain compensation lookup table 1.1) Based on the principle of effectiveness of digital baseband signal predistortion at a given frequency point, the shortwave frequency is divided into K continuous frequency intervals. The digital predistortion system operates in a certain frequency interval, obtains output power data for that frequency interval, and feeds it back for predistortion processing to obtain a lookup table (LUT) for that frequency interval. Repeat the above steps to obtain a LUT for K frequency intervals; the K continuous frequency intervals are f_1, f_2, ..., f_K. 1.2) While establishing a LUT lookup table for K frequency intervals in the digital pre-distortion system, the shortwave frequency is divided into M continuous frequency intervals to obtain a gain compensation lookup table for the M frequency intervals; the M continuous frequency intervals are F_1, F_2, ..., F_M; The M frequency intervals are divided into shortwave frequencies based on the principle of being able to compensate for the unevenness of the digital baseband signal in real time under the communication state; 2) Digital pre-distortion processing through the pre-distortion channel 2.1) When a digital baseband signal X(n) at a certain frequency arrives, the digital predistortion system multiplies the LUT index result by the input signal X(n) at that moment to obtain the amplitude predistortion signal X_DPD(n). The system then multiplies the gain compensation value obtained by indexing the gain compensation lookup table at a certain frequency by the amplitude predistortion signal X_DPD(n) to obtain the corrected predistortion signal Z(n). 2.2) Based on the relationship between the predistortion signal Z(n) output by the digital predistortion system and the input signal X(n) at the current moment, the LUT lookup table and the gain compensation lookup table are updated in real time, and predistortion processing of the input signal at the next moment is continued until the digital predistortion processing of the digital baseband signal is completed.

2. The digital predistortion method capable of integrated correction of the frequency response of a shortwave power amplifier according to claim 1, wherein step 2.1) specifically comprises: 2.1.1) After the power calculation of the digital baseband signal X(n) corresponding to frequency point i, the corresponding amplitude is obtained. The amplitude is used as the address of the LUT of frequency point i, and the LUT lookup table LUT(1) to LUT(N) corresponding to the frequency interval f_i where frequency point i is located is indexed to obtain the corresponding LUT value, and the LUT value is multiplied by the digital baseband signal X(n) at the current moment to obtain the amplitude predistortion signal X_DPD(n); 2.1.2) Look up the gain compensation Gain(i) corresponding to the frequency point i in the gain compensation lookup table corresponding to the frequency interval F_i where the frequency point i is located, and multiply the gain compensation by the amplitude predistortion signal X_DPD(n) to obtain the corrected predistortion signal Z(n).

3. The digital predistortion method capable of integrated correction of the frequency response of a shortwave power amplifier according to claim 2, characterized in that: In step 2.1.1), N=128.

4. The digital predistortion method capable of integrating and correcting the frequency response of a shortwave power amplifier according to claim 1, wherein: Step 2.2) is specifically as follows: 2.2.1) Calculate the normalized mean square error (NMSE) between the current digital baseband input signal and the predistortion output signal. dB ; 2.2.2) Determine the normalized mean square error NMSE dB Is it greater than the preset target value? If yes, the predistortion parameters are calculated using the least squares method, and the predistortion parameters in the corresponding LUT lookup table are replaced with the parameters, and the process returns to step 2) for predistortion processing; Otherwise, the predistortion processing of the current digital baseband input signal is terminated, and the predistortion processing of the next input signal continues to use the current lookup table until the digital predistortion processing of the digital baseband signal is completed.

5. The digital predistortion method capable of integrated correction of the frequency response of a shortwave power amplifier according to any one of claims 1 to 4, characterized in that: In step 1.1), the frequency intervals of the K consecutive frequency intervals are the same; In step 1.2), the frequency intervals of the M consecutive frequency intervals are the same.

6. The digital predistortion method capable of integrated correction of the frequency response of a shortwave power amplifier according to claim 5, characterized in that: In step 1.1), the frequency interval of the K consecutive frequency intervals is 100 KHz; In step 1.2), the frequency interval of the M consecutive frequency intervals is 1 MHz.

7. A computer storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the digital predistortion method capable of integrating and correcting the frequency response of a shortwave power amplifier as claimed in any one of claims 1 to 6 are implemented.

8. A computer device comprising a processor, a memory connected to the processor, and a computer program executable on the memory, wherein: When the processor executes the computer program, the steps of the digital predistortion method capable of integrating and correcting the frequency response of a shortwave power amplifier as described in any one of claims 1 to 6 are implemented.

Images