CN115940833B - Digital predistortion method, storage medium and device capable of integrated correction of shortwave power amplifier frequency response - Google Patents
Digital predistortion method, storage medium and device capable of integrated correction of shortwave power amplifier frequency responseInfo
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- CN115940833B CN115940833B CN202211435581.2A CN202211435581A CN115940833B CN 115940833 B CN115940833 B CN 115940833B CN 202211435581 A CN202211435581 A CN 202211435581A CN 115940833 B CN115940833 B CN 115940833B
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Abstract
本发明为解决短波发射机为提升发射机的效率采用数字预失真技术时，对短波发射机工作带宽内在不同频点的行为特性并不相同，导致通信系统传输效率下降，产生邻道干扰，增加接收机的误码率，影响短波发射整机的稳定性的问题，而提供一种可整合校正短波功率放大器频率响应的数字预失真方法、存储介质和设备。本发明将短波频率划分为K个频率区间，对每个频率区间内的频点进行幅度索引，得到自适应的预失真系数和查找表，再将短波频率划分为M个频率区间，根据每个频率区间对应的增益补偿表，对所有频点进行频率索引，将对应频点的增益补偿值与幅值补偿后预失真信号进行实时整合补偿，获得特性更为平稳的短波功率放大器频率响应的数字预失真信号。
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
The invention relates to the technical field of digital predistortion, in particular to a digital predistortion method, a storage medium and equipment capable of integrally correcting the frequency response of a short wave power amplifier.
Background
With the development of digital mobile communication technology, higher and higher requirements are put forward on the performance of a base station power amplifier, namely, the power amplifier has higher efficiency on the premise of meeting higher linearity requirements. To meet this requirement, the amplifier is made both linear and efficient, i.e. a linearization process is required for a radio frequency amplifier or radio frequency system.
The frequency of the radio electromagnetic wave with the frequency range of 1.6 MHz-30 MHz is generally called a short-wave frequency band, the radio frequency capable of receiving a certain frequency is generally called a short-wave radio station, and the radio frequency is used for carrying out worldwide broadcast transmission by utilizing the short-wave frequency to carry out one-way communication and is generally called short-wave broadcast. Because short wave communication mainly relies on back and forth reflection and refraction between the ionosphere and the ground for propagation, short waves can propagate far no matter in daytime or at night. With the continuous development of computer, microelectronics and wireless communication technologies, the short-wave communication technology has breakthrough progress, and the short-wave communication technology is used for emergency communication and disaster-resistant communication, and particularly plays an important and wide role in the aspect of land, sea and air unified communication command required by military.
Currently, short-wave radio stations have become digitalized, and the working frequency band of the short-wave radio stations is not limited to the original short-wave frequency band range, so that the short-wave radio stations have the characteristics of multiple bands and multiple channels. In the digitizing process of the short-wave radio station, the performance of the short-wave power amplifier is required to be higher and higher, namely, the power amplifier has higher efficiency on the premise of meeting higher linearity requirements.
To meet this requirement, the amplifier is made both linear and efficient, and various means are employed to achieve high efficiency and high linearity of the amplifier. The most important step in the development of the power amplifier linearization technology is the occurrence of the predistortion technology, which is initially applied to the radio frequency part in the analog communication system, and along with the development of the digital signal processing technology, the predistortion technology can also be realized in the digital domain to form the digital predistortion technology. The predistortion technology not only can improve the efficiency of the transmitter and reduce the cost and the volume, but also can effectively increase the linearity of the transmitter to improve the system efficiency and the communication quality, and has great practical significance for the development and the realization of future high-efficiency short-wave radio stations. For easy implementation, the digital predistortion system adopts a look-up Table (LUT) method. In the method, the predistortion LUT extraction structure is mainly used for a digital predistortion system through a predistortion LUT which is corrected and output by continuous iteration.
Digital predistortion techniques are based on processing a baseband signal that corresponds to the envelope of a radio frequency signal. In theory, the power amplifier should have the same frequency characteristic for all frequency points in the working bandwidth, namely the gain and nonlinearity of the power amplifier, and have the same characteristics, but since the actual power amplifier cannot do so, the behavior characteristics of the power amplifier at different frequency points are not the same, so that the predistortion model established by collecting signals at one radio frequency point is not necessarily applicable to other frequency points.
On the basis of the above, further consideration is given to the fact that in short wave transmitters, when the power amplifier is highly efficient, the system tends to operate in a nonlinear state. This not only results in a decrease in transmission efficiency of the communication system, but also generates adjacent channel interference, which greatly increases the error rate of the receiver. According to the GJB regulation and the requirements of the whole machine in practical application, the flatness of the gain of the power amplifier is generally required to be +/-1 dB, namely the maximum tolerance of the frequency response in the short wave effective frequency range (2-30 MHz) is not more than 2dB. However, since the transmission power of the short-wave power amplifier is generally larger, for example, for a 200W short-wave power amplifier, the 1dB fluctuation can generate 50W transmission power change, thereby affecting the stability of the short-wave transmission complete machine. Therefore, the method for improving the linearity and flatness of the power amplifier has important significance for improving the stability of the output power of the power amplifier and the effectiveness of a transmitter service system and a communication system.
Disclosure of Invention
The invention aims to solve the problems that the prior short wave transmitter adopts a digital predistortion technology for improving the efficiency of the transmitter, wherein the behavior characteristics of different frequency points in the working bandwidth of the short wave transmitter are different, so that the transmission efficiency of a communication system is reduced, adjacent channel interference is generated, the error rate of a receiver is increased, and the stability of the whole short wave transmitter is influenced.
In order to achieve the above purpose, the invention adopts the following technical scheme:
the digital predistortion method capable of integrally correcting the frequency response of the short wave power amplifier is characterized by comprising the following steps of:
1) Establishing LUT lookup table and gain compensation lookup table
1.1 Dividing a short wave frequency into K continuous frequency intervals by taking the effectiveness of a predistortion effect of a digital baseband signal at a set frequency point as a principle, and running a digital predistortion system in a certain frequency interval to obtain output power data of the frequency interval, feeding back to perform predistortion treatment to obtain an LUT lookup table of the frequency interval;
1.2 The method comprises the steps of) establishing an LUT lookup table of K frequency intervals by a digital predistortion system, dividing a short wave frequency into M continuous frequency intervals, and obtaining a gain compensation lookup table of the M frequency intervals, wherein the M continuous frequency intervals are F_1, F_2 and F_M respectively;
The M frequency intervals divide short wave frequencies according to the principle that the in-band unevenness of the digital baseband signal can be compensated in real time in a communication state;
2) Digital predistortion processing via predistortion channels
2.1 When the digital baseband signal X (n) under a certain frequency point arrives, the digital predistortion system multiplies the index result of the LUT lookup table with the input signal X (n) at the moment to obtain an amplitude predistortion signal X_DPD (n);
2.2 According to the relation between the predistortion signal Z (n) output by the digital predistortion system when in operation and the input signal X (n) at the current moment, updating the LUT lookup table and the gain compensation lookup table in real time, and continuing the predistortion processing of the input signal at the next moment until the digital predistortion processing of the digital baseband signal is completed.
Further, step 2.1) specifically comprises:
2.1.1 The digital baseband signal X (N) corresponding to the frequency point i is subjected to power calculation to obtain a corresponding amplitude, the amplitude is used as an address of an LUT of the frequency point i, indexes are carried out in LUT lookup tables LUT (1) -LUT (N) corresponding to a frequency interval f_i where the frequency point i is located, a corresponding LUT value is obtained, and the corresponding LUT value is multiplied with the digital baseband signal X (N) at the current moment to obtain an amplitude predistortion signal X_DPD (N);
2.1.2 Searching a Gain compensation Gain (i) corresponding to the frequency point i in a Gain compensation lookup table corresponding to the frequency interval F_i where the corresponding frequency point i is located, and multiplying the Gain compensation with the amplitude predistortion signal X_DPD (n) to obtain a corrected predistortion signal Z (n).
Further, in step 2.1.1), n=128.
Further, step 2.2) specifically comprises:
2.2.1 Calculating a normalized mean square error NMSE dB for the current digital baseband input signal and the predistortion output signal;
2.2.2 Judging whether the normalized mean square error NMSE dB is larger than a preset target value;
if yes, calculating predistortion parameters by using a least square method, replacing predistortion parameters of a corresponding LUT lookup table with the parameters, and returning to the step 2) for predistortion treatment;
Otherwise, the predistortion processing of the current digital baseband input signal is ended, and the predistortion processing of the next input signal continues to adopt the current lookup table until the digital predistortion processing of the digital baseband signal is completed.
Further, 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.
Further, in step 1.1), the frequency interval of the K consecutive frequency intervals is 100KHz;
in step 1.2), the M consecutive frequency intervals have a frequency interval of 1MHz.
The invention also provides a computer storage medium, on which a computer program is stored, which is characterized in that the computer program, when executed by a processor, realizes the steps of the digital predistortion method capable of integrally correcting the frequency response of the short-wave power amplifier.
The invention also provides a computer device which comprises a processor, a memory connected with the processor and a computer program capable of running on the memory, and is characterized in that the processor realizes the steps of the digital predistortion method capable of integrally correcting the frequency response of the short-wave power amplifier when executing the computer program.
Compared with the prior art, the invention has the following beneficial technical effects:
1. The digital predistortion method capable of integrating and correcting the frequency response of the short-wave power amplifier can be used for simultaneously integrating and correcting the frequency response of the short-wave power amplifier, so that the performance of a digital predistortion system is improved, and the stability of the output power of the power amplifier and the effectiveness of a transmitter service system and a communication system are further improved.
2. The digital predistortion method capable of integrally correcting the frequency response of the short-wave power amplifier provided by the invention adopts a fitting method including a segmentation method including but not limited to a least square method to calibrate the frequency response of the power amplifier in an off-line state, compensates the unevenness in real time in a communication state, and obtains the digital predistortion signal with smoother characteristic of the frequency response of the short-wave power amplifier.
Drawings
FIG. 1 is a diagram of the overall structure of a prior art predistortion architecture;
FIG. 2 is a diagram illustrating the extraction of a pre-distortion table according to the prior art;
FIG. 3 is a diagram of a prior art predistortion model table index block;
FIG. 4 is a diagram of LUT architecture corresponding to predistortion table power calculation magnitude index;
FIG. 5 is a graph showing the actual measurement result of the frequency response of a 125W short wave power amplifier;
fig. 6 is a diagram of a digital predistortion architecture for integrally correcting the frequency response of a short wave power amplifier according to an embodiment of the present invention.
Detailed Description
To make the objects, advantages and features of the present invention more apparent, a digital predistortion method, storage media and apparatus for integrally correcting the frequency response of a short wave power amplifier are described in further detail below with reference to the accompanying drawings and detailed description. It should be understood by those skilled in the art that these embodiments are merely for explaining the technical principles of the present invention, and are not intended to limit the scope of the present invention.
As shown in fig. 1, a predistortion architecture of the prior art employs a look-up Table (LUT) method, in which predistortion of this form is operated by means of a LUT which is retrieved as a function of the amplitude of the signal, or input amplitude, and then the amplitude and phase of the signal applied to the input of the power amplifier are modified to cancel the distortion thereof. The predistortion system architecture comprises two channels, a loop channel for data training and a predistortion channel. The data training channel is a loop structure, the core part of the data training channel is a predistortion algorithm module, and the module obtains the distortion characteristic of the power amplifier by processing the feedback output signal (the signal after output coupling of the power amplifier) and the original input signal after the power amplifier, thereby obtaining the LUT parameter of the distortion inverse characteristic of the power amplifier. When the power amplifier characteristics change with time or external environment changes, predistortion inverse LUT parameters can be updated by an adaptive predistortion algorithm.
Fig. 2 is a schematic diagram of a predistortion parameter extraction method in the prior art. Wherein X is an input signal and Y is a feedback signal. Firstly, determining output power according to requirements, firstly, enabling a system to be directly connected, enabling LUT parameters to be all defined as '1', enabling LUT (X) =X, enabling signals to pass through a power amplifier to obtain a first group of output data, feeding back to carry out predistortion, obtaining the LUT parameters by solving min|LUT (Y) -LUT (X) |, continuously correcting the LUT parameters in an iterative process until the output signal Y obtains a satisfactory effect, extracting the LUT parameters at the moment to serve as a predistortion LUT under the output power, enabling the LUT parameters to be used by the system in the form of LUT (1) -LUT (N), and enabling N to be selected according to system resources and performance requirements, and taking 128.
As shown in fig. 3, a predistortion model table index block diagram of the prior art is shown. The LUT parameters are power-calculated from the input data to obtain the corresponding table index address |x (n) |, then the corresponding LUT parameters, i.e., LUT (|x (n) |), are obtained, and then the amplitude and phase of the signal X (n) applied to the input of the power amplifier are corrected to obtain the pre-distorted DPD (X (n)).
As shown in fig. 4, a LUT architecture diagram corresponding to the predistortion table power calculation amplitude index is shown. In a digital predistortion system, power amplifier modeling and predistortion coefficient estimation are required, and floating point operation is adopted to ensure the accuracy of modeling and coefficient calculation. The direct floating point operation by using a hardware circuit in the FPGA wastes a great deal of resources and the working speed is reduced, so that the prior predistortion platform generally puts the part of functions into an ARM processor or a DSP, and then an ARM+FPGA architecture and a DSP+FPGA architecture are provided.
The predistortion model established by the acquisition signal of one radio frequency point as mentioned in the background art is not necessarily applicable to other frequency points. The greater the difference in carrier frequencies of the radio frequency signals, the poorer the predistortion optimization. Therefore, it is necessary to build predistortion models for the power amplifier at different frequency points, after analyzing the coverage range of the predistortion linearity optimization effect of a single frequency point on the frequency, under the condition of using as few hardware resources as possible, the predistortion models are respectively built at each frequency point interval (f_1-f_K) at certain frequency intervals in the working range of the short-wave radio station of 1.6 MHz-30.0 MHz, so as to ensure the effectiveness of the predistortion effect at the set frequency point, the frequency point number K at the position can be selected according to the system resources and performance requirements, and the frequency interval at the position is 100KHz.
The digital predistortion system specifically comprises a DPD initialization process, wherein an I path parameter in a RAM table of a predistorter is set to be 1, a Q path parameter is set to be 0, a frequency point value to be predistorted is judged after clock enabling, a frequency point i=1 represents a first frequency point (i=1, 2, 3.) and an enabling signal corresponding to the frequency point is input at the same time for enabling the LUT parameter corresponding to the frequency point.
The better the consistency of the characteristics of the power amplifier in the amplifying frequency band, the wider the optimized frequency range of the predistortion is, so that the gain fluctuation of the power amplifier should be reduced as much as possible in the process of designing the power amplifier, and the characteristics of the power amplifier in the working frequency band of the power amplifier tend to be stable. Short wave radio working range is 1.6 MHz-30.0 MHz the maximum tolerance of the frequency response does not exceed 2dB. Fig. 5 is a graph showing the actual measurement result of the frequency response of a 125W short-wave power amplifier. Because the short wave transmitter has certain frequency response, the obtained power amplifier output needs to be further calibrated according to the frequency response curve in the working frequency range of the short wave radio station, thereby ensuring that the radio station compensates the in-band unevenness in real time in the communication state.
In order to reduce the resources consumed by the actual measurement, the invention adopts a fitting method including but not limited to a least square method to obtain more subdivided power amplifier output power calibration parameters in an offline state, and the method is used for compensating the in-band unevenness in real time in a communication state (in order to meet the requirement of gain compensation values which may be finer in certain scenes). The number M of the output power calibration parameters of the power amplifier can be selected according to the system resource and performance requirements, and the frequency interval is 1MHz.
To ensure that the calibration data in the measurement state is available for each power-up of each actuator, calibration function data is stored in the ROM. When the system is started, firstly, a data space appointed by the ROM is called, a gain compensation value (frequency response correction coefficient) is configured, and a gain compensation table is obtained so as to ensure calling during normal operation. The invention adopts a two-dimensional index digital predistortion system structure with frequency indexes and amplitude indexes of predistortion tables, and further integrates and corrects the frequency response of the short-wave power amplifier on the basis, and fig. 6 is a diagram of the digital predistortion structure for integrating and correcting the frequency response of the short-wave power amplifier.
The invention provides a digital predistortion method capable of integrally correcting the frequency response of a short-wave power amplifier, which specifically comprises the following steps:
1) Establishing LUT lookup table and gain compensation lookup table
1.1 Dividing the short wave frequency into K continuous frequency intervals (f_1, f_2,., f_K) by taking the effectiveness of the predistortion effect of the digital baseband signal at a set frequency point as a principle, and operating the digital predistortion system in a certain frequency interval to obtain output power data of the frequency interval, feeding back to carry out predistortion treatment to obtain an LUT lookup table of the frequency interval;
the number of LUT look-up tables corresponding to each frequency interval is N, i.e., LUT (1) through LUT (N), where N may be selected according to system resource and performance requirements, and 128 is taken here.
For example, the working range of the short-wave radio station is 1.6 MHz-30.0 MHz, and the frequency interval can be 100KHz.
The digital baseband signal is processed by a digital predistorter to obtain a predistortion signal, the predistortion signal is converted into an analog signal by a digital-to-analog converter and amplified by a power amplifier to obtain an amplified analog signal, the amplified analog signal is coupled and attenuated by a post attenuator and is converted into a digital signal by the analog-to-digital converter to be transmitted to a predistortion parameter extraction module, and the predistortion parameter extraction module processes the acquired digital signal and predistortion signal to obtain predistortion parameters, namely an LUT (look-up table);
1.2 Dividing short wave frequency into M continuous frequency intervals (F_1, F_2, & gt, F_M) while establishing an LUT lookup table of K frequency intervals by a digital predistortion system, and obtaining gain compensation lookup tables of the M frequency intervals;
The M frequency intervals divide short wave frequencies according to the principle that the in-band unevenness of the digital baseband signal can be compensated in real time in a communication state;
the short wave frequency division may specifically divide the operating range of the digital baseband signal by the same frequency interval.
2) Digital predistortion processing via predistortion channels
2.1 When the digital baseband signal X (n) under a certain frequency point arrives, the digital predistortion system multiplies the index result of the LUT lookup table with the input signal X (n) at the moment to obtain an amplitude predistortion signal X_DPD (n);
2.1.1 The digital baseband signal X (N) corresponding to the frequency point i (1 is less than or equal to i is less than or equal to K) is subjected to power calculation to obtain a corresponding amplitude, the amplitude is used as the address of the LUT of the frequency point i, indexes are carried out in LUT lookup tables LUT (1) -LUT (N) corresponding to the frequency interval f_i where the frequency point i is located, a corresponding LUT value is obtained, and the corresponding LUT value is multiplied with the input signal X (N) at the current moment to obtain an amplitude predistortion signal X_DPD (N);
2.1.2 Searching a Gain compensation Gain (i) corresponding to a section where a digital baseband signal X (n) of a corresponding frequency point i (i is more than or equal to 1 and less than or equal to M) is located in a Gain compensation lookup table corresponding to a frequency section f_i where the corresponding frequency point i is located, and multiplying the Gain compensation with an amplitude predistortion signal X_DPD (n) to obtain a corrected predistortion signal Z (n).
2.2 According to the relation between the predistortion signal Z (n) output by the digital predistortion system when in operation and the input signal X (n) at the current moment, updating the LUT lookup table and the gain compensation lookup table in real time, and continuing the predistortion processing of the input signal at the next moment. The method comprises the following steps:
2.2.1, calculating a normalized mean square error NMSE dB of the current input signal and the predistortion output signal;
2.2.2, judging whether the calculated normalized mean square error NMSE dB is larger than a preset target value;
If yes, calculating predistortion parameters by using a least square method, updating a corresponding LUT lookup table, and returning to the step 2) for predistortion treatment;
Otherwise, the predistortion processing of the round is ended, and the predistortion processing of the next input signal continues to adopt the current lookup table until the digital predistortion processing of the digital baseband signal is completed.
The digital baseband signal of the intermediate frequency point i is subjected to frequency indexing once, so that the corresponding predistortion result and the corresponding gain compensation result can be integrated and compensated in real time, and the digital predistortion signal with more stable characteristics and of the frequency response of the short-wave power amplifier is obtained.
All or part of the steps of implementing the above method embodiments may be implemented by hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, where the program when executed performs the steps including the above method embodiments, where the storage medium includes various media capable of storing program codes, such as ROM, RAM, magnetic disk, or optical disk.
Corresponding to the above method embodiments, the present application further provides a computer readable storage medium, on which a computer program is stored, which when executed by a processor implements the steps of the external storage medium detection method described above.
The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. The software modules may be disposed in Random Access Memory (RAM), memory, read Only Memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.
It should be noted that the above-mentioned embodiments are merely for illustrating the technical solution of the present invention, and not for limiting the same, and although the present invention has been described in detail with reference to the above-mentioned embodiments, it should be understood by those skilled in the art that the technical solution described in the above-mentioned embodiments may be modified or some or all of the technical features may be equivalently replaced, and these modifications or substitutions do not deviate from the essence of the corresponding technical solution from the scope of the technical solution of the present invention.
Claims (8)
1. The digital predistortion method capable of integrally correcting the frequency response of the short wave power amplifier comprises the following steps:
1) Establishing LUT lookup table and gain compensation lookup table
1.1 Dividing a short wave frequency into K continuous frequency intervals by taking the effectiveness of a predistortion effect of a digital baseband signal at a set frequency point as a principle, and running a digital predistortion system in a certain frequency interval to obtain output power data of the frequency interval, feeding back to perform predistortion treatment to obtain an LUT lookup table of the frequency interval;
1.2 The method comprises the steps of) establishing an LUT lookup table of K frequency intervals by a digital predistortion system, dividing a short wave frequency into M continuous frequency intervals, and obtaining a gain compensation lookup table of the M frequency intervals, wherein the M continuous frequency intervals are F_1, F_2 and F_M respectively;
The M frequency intervals divide short wave frequencies according to the principle that the in-band unevenness of the digital baseband signal can be compensated in real time in a communication state;
2) Digital predistortion processing via predistortion channels
2.1 When the digital baseband signal X (n) under a certain frequency point arrives, the digital predistortion system multiplies the index result of the LUT lookup table with the input signal X (n) at the moment to obtain an amplitude predistortion signal X_DPD (n);
2.2 According to the relation between the predistortion signal Z (n) output by the digital predistortion system when in operation and the input signal X (n) at the current moment, updating the LUT lookup table and the gain compensation lookup table in real time, and continuing the predistortion processing of the input signal at the next moment until the digital predistortion processing of the digital baseband signal is completed.
2. The method of digital predistortion for integrally correcting the frequency response of a short wave power amplifier according to claim 1, wherein step 2.1) comprises:
2.1.1 The digital baseband signal X (N) corresponding to the frequency point i is subjected to power calculation to obtain a corresponding amplitude, the amplitude is used as an address of an LUT of the frequency point i, indexes are carried out in LUT lookup tables LUT (1) -LUT (N) corresponding to a frequency interval f_i where the frequency point i is located, a corresponding LUT value is obtained, and the corresponding LUT value is multiplied with the digital baseband signal X (N) at the current moment to obtain an amplitude predistortion signal X_DPD (N);
2.1.2 Searching a Gain compensation Gain (i) corresponding to the frequency point i in a Gain compensation lookup table corresponding to the frequency interval F_i where the corresponding frequency point i is located, and multiplying the Gain compensation with the amplitude predistortion signal X_DPD (n) to obtain a corrected predistortion signal Z (n).
3. The method for digital predistortion for integrally correcting the frequency response of a short wave power amplifier according to claim 2, wherein:
step 2.1.1), n=128.
4. The method of digital predistortion for integrally correcting the frequency response of a short wave power amplifier according to claim 1, wherein step 2.2) comprises:
2.2.1 Calculating a normalized mean square error NMSE dB for the current digital baseband input signal and the predistortion output signal;
2.2.2 Judging whether the normalized mean square error NMSE dB is larger than a preset target value;
if yes, calculating predistortion parameters by using a least square method, replacing predistortion parameters of a corresponding LUT lookup table with the parameters, and returning to the step 2) for predistortion treatment;
Otherwise, the predistortion processing of the current digital baseband input signal is ended, and the predistortion processing of the next input signal continues to adopt the current lookup table until the digital predistortion processing of the digital baseband signal is completed.
5. The method for digital predistortion for integrally correcting the frequency response of a short wave power amplifier according to any one of claims 1 to 4, wherein:
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 method for digital predistortion for integrally correcting the frequency response of a short wave power amplifier of claim 5 wherein:
in the step 1.1), the frequency interval of the K continuous frequency intervals is 100KHz;
in step 1.2), the M consecutive frequency intervals have a frequency interval of 1MHz.
7. A computer storage medium having a computer program stored thereon, characterized by:
The computer program, when executed by a processor, implements the steps of the digital predistortion method of integrable correction of the frequency response of a short wave power amplifier as claimed in any one of claims 1 to 6.
8. A computer device comprising a processor, a memory coupled to the processor, and a computer program executable on the memory, characterized by:
the processor, when executing the computer program, implements the steps of the digital predistortion method of integrable correction of the frequency response of a short wave power amplifier as claimed in any one of claims 1 to 6.
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