CN115940833A - Digital predistortion method, storage medium and apparatus for integrated correction of frequency response of shortwave power amplifier - Google Patents
Digital predistortion method, storage medium and apparatus for integrated correction of frequency response of shortwave power amplifier Download PDFInfo
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Abstract
The invention provides a digital predistortion method, a storage medium and equipment capable of integrally correcting frequency response of a short-wave power amplifier, aiming at solving the problems that when a short-wave transmitter adopts a digital predistortion technology to improve the efficiency of the transmitter, 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 due to different behavior characteristics of different frequency points in the working bandwidth of the short-wave transmitter. The method comprises the steps of dividing short wave frequency into K frequency intervals, conducting amplitude indexing on frequency points in each frequency interval to obtain self-adaptive predistortion coefficients and a lookup table, dividing the short wave frequency into M frequency intervals, conducting frequency indexing on all the frequency points according to a gain compensation table corresponding to each frequency interval, conducting real-time integration compensation on gain compensation values of corresponding frequency points and predistortion signals after amplitude compensation, and obtaining digital predistortion signals with more stable characteristics of frequency response of the short wave 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 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, on the premise of meeting higher linearity requirements, the power amplifier has higher efficiency. To meet this requirement, the amplifier needs to be linear and efficient, i.e. a linear processing requirement is provided for the radio frequency amplifier or the radio frequency system.
Radio electromagnetic wave frequencies in the frequency range of 1.6MHz to 30MHz are generally called short wave bands, and radio sets capable of receiving a certain frequency are generally called short wave broadcasting stations, which use short wave frequencies to perform one-way communication in broadcast transmission in the world. Because the short-wave communication is mainly transmitted by back-and-forth reflection and refraction between the ionized layer and the ground, the short wave can be transmitted far no matter day or night. With the continuous development of computer, microelectronic and wireless communication technologies, the short wave communication technology has breakthrough development, and the short wave communication technology plays more important and wider roles in emergency communication, disaster-resistant communication, and particularly in military requirement unified communication command of land, sea and air.
At present, short-wave radio stations are increasingly digitized, and the working frequency band 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 digitization process of the short-wave radio station, higher and higher requirements are provided for the performance of the short-wave power amplifier, namely, the power amplifier has higher efficiency on the premise of meeting higher linear requirements.
To meet this requirement, the amplifier is linear and efficient, and various means are used to achieve high efficiency and high linearity of the amplifier. The most important step in the development of power amplifier linearization technology is the emergence of predistortion technology, which is initially applied to the radio frequency part in an analog communication system and can also be realized in the digital domain along with the development of digital signal processing technology to form digital predistortion technology. The predistortion technology not only can improve the efficiency of the transmitter, reduce the cost and reduce the volume, but also can effectively increase the linearity of the transmitter so as to improve the system efficiency and the communication quality, and has great practical significance for the development and the realization of a future high-efficiency short-wave radio station. For the convenience of implementation, the digital predistortion system adopts a Lookup 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 continuously iterated to carry out correction output.
Digital predistortion techniques are based on processing of a baseband signal, which corresponds to the envelope of a radio frequency signal. Theoretically, the power amplifier should have the same frequency characteristics for all frequency points in the working bandwidth, that is, the gain and nonlinearity of the power amplifier have the same characteristics, but because the actual power amplifier cannot achieve the same point and the behavior characteristics of the power amplifier at different frequency points are different, 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 considering that in a practical short-wave transmitter, when the power amplifier is highly efficient, the system tends to operate in a nonlinear state. This not only results in a reduction in the transmission efficiency of the communication system, but also generates adjacent channel interference, greatly increasing the error rate of the receiver. According to the GJB regulations and the requirements on the whole machine in practical application, the power amplifier gain flatness is generally required to be +/-1 dB, namely the maximum tolerance of the frequency response in a short wave effective frequency range (2-30 MHz) is not more than 2dB. However, the transmission power of the short-wave power amplifier is generally larger, for example, for a 200W short-wave power amplifier, a 50W transmission power variation is generated by 1dB fluctuation, and thus the stability of the short-wave transmission complete machine is affected. Therefore, the method 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 behavioral 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, and provides a digital predistortion method, a storage medium and equipment capable of integrally correcting the frequency response of a short-wave power amplifier.
In order to achieve the purpose, the invention adopts the technical scheme that:
a digital predistortion method for integrally correcting the frequency response of a shortwave power amplifier is characterized by comprising the following steps:
1) Establishing LUT lookup tables and gain compensation lookup tables
1.1 Taking effectiveness of a predistortion effect of a digital baseband signal at a set frequency point as a principle, dividing short wave frequency into K continuous frequency intervals, operating a digital predistortion system in a certain frequency interval to obtain output power data of the frequency interval, and feeding back to perform predistortion treatment to obtain an LUT lookup table of the frequency interval; repeating the steps to obtain an LUT lookup table of K frequency intervals; the K continuous frequency intervals are f _1, f _2, a.
1.2 While the digital predistortion system establishes an LUT lookup table of K frequency intervals, short wave frequency is divided into M continuous frequency intervals to obtain gain compensation lookup tables of the M frequency intervals; the M consecutive frequency intervals are F _1, F _2,. And F _ M respectively;
the M frequency intervals divide short wave frequency according to the principle that unevenness in a digital baseband signal band can be compensated in real time in a communication state;
2) Digital predistortion processing through a predistortion channel
2.1 When a digital baseband signal X (n) at a certain frequency comes, the digital predistortion system multiplies the LUT lookup table index result by the input signal X (n) at the moment to obtain an amplitude predistortion signal X _ DPD (n); multiplying a gain compensation value obtained by an index gain compensation lookup table at a certain frequency point by the amplitude predistortion signal X _ DPD (n) to obtain a corrected predistortion signal Z (n);
2.2 According to the relationship between the predistortion signal Z (n) output by the digital predistortion system during operation 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 input signal predistortion processing at the next moment is continued until the digital predistortion processing of the digital baseband signal is completed.
Further, the step 2.1) is specifically as follows:
2.1.1 Power calculation is carried out on the digital baseband signal X (N) corresponding to the frequency point i 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 to obtain a corresponding LUT value, 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 And searching Gain compensation Gain (i) corresponding to the frequency point i in a Gain compensation lookup table corresponding to a frequency interval F _ i where the corresponding frequency point i is located, and multiplying the Gain compensation and the amplitude predistortion signal X _ DPD (n) to obtain a corrected predistortion signal Z (n).
Further, in step 2.1.1), N =128.
Further, the step 2.2) is specifically as follows:
2.2.1 Computing a normalized mean square error NMSE of a current digital baseband input signal and a predistorted output signal dB ；
2.2.2 ) determining the normalized mean square error NMSE dB Whether the target value is greater than a preset target value;
if yes, calculating a predistortion parameter by adopting a least square method, replacing the predistortion parameter of the corresponding LUT lookup table by the parameter, and returning to the step 2) for predistortion treatment;
otherwise, the predistortion processing of the current digital baseband input signal is finished, 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 finished.
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 frequency interval of the M consecutive frequency intervals is 1MHz.
The invention also provides a computer storage medium having a computer program stored thereon, characterized in that: the computer program when executed by a processor implements the steps of the above-described digital predistortion method for integratably correcting the frequency response of a shortwave 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, when executing the computer program, performs the steps of the above-described method for digital predistortion that may integrally correct the frequency response of a shortwave power amplifier.
Compared with the prior art, the invention has the following beneficial technical effects:
1. the digital predistortion method capable of integrally correcting the frequency response of the short-wave power amplifier provided by the invention can be used for simultaneously integrally correcting the frequency response of the short-wave power amplifier, thereby improving the performance of a digital predistortion system, and further improving the stability of power amplifier output power and the effectiveness of a transmitter service system and a communication system.
2. The digital predistortion method capable of integrally correcting the frequency response of the short-wave power amplifier provided by the invention is used for calibrating the frequency response of the power amplifier by adopting a fitting method including but not limited to a least square method in a segmented mode in an off-line state and compensating unevenness in a communication state in real time, and the digital predistortion signal with the frequency response of the short-wave power amplifier with more stable characteristics is obtained by adopting the predistortion method provided by the invention.
Drawings
Fig. 1 is a diagram illustrating an overall structure of a conventional predistortion structure;
FIG. 2 is a diagram illustrating a conventional extraction of a pre-distortion table;
FIG. 3 is a diagram of a table index structure of a pre-distortion model in the prior art;
FIG. 4 is a diagram of an LUT architecture corresponding to a predistortion table power calculation amplitude index;
FIG. 5 is a diagram of measured frequency response of a 125W short-wave power amplifier;
fig. 6 is a diagram of a digital predistortion architecture for integrated correction of the frequency response of a short wave power amplifier in accordance with 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, a storage medium and an apparatus for integrally correcting a frequency response of a short wave power amplifier according to the present invention are described in further detail with reference to the accompanying drawings and specific embodiments. It should be understood by those skilled in the art that these embodiments are only for explaining the technical principle of the present invention and are not intended to limit the scope of the present invention.
As shown in fig. 1, one predistortion architecture of the prior art employs a look-up Table (LUT) approach, this form of predistortion operating with an LUT that is retrieved as a function of the amplitude of the signal, or input amplitude, and then modifies the amplitude and phase of the signal applied to the input of the power amplifier to cancel its distortion. The predistortion system architecture contains two channels: a loop path for data training and a predistortion path. The data training channel is a loop structure, the core part of the data training channel is a predistortion algorithm module, and the module processes a feedback output signal (a signal after the output coupling of the power amplifier) after passing through the power amplifier and an original input signal to obtain the distortion characteristic of the power amplifier, so as to obtain the LUT parameter of the distortion inverse characteristic of the power amplifier. When the power amplifier characteristic changes with time or external environment, the predistortion inverse characteristic LUT parameter can be updated by the 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, when the system runs for the first time, enabling the system to be in a straight-through state, defining all LUT parameters as '1', LUT (X) = X, obtaining a first group of output data after a signal passes through a power amplifier, feeding back to perform predistortion, obtaining LUT parameters by solving min | LUT (Y) -LUT (X) |, continuously correcting the LUT parameters in an iteration process until the output signal Y obtains a satisfactory effect, extracting the LUT parameters at the moment as a predistortion LUT under the output power, and providing the predistortion LUT parameters for the system in the form of LUT (1) -LUT (N), wherein N can be selected according to system resources and performance requirements, and is 128.
Fig. 3 is a diagram showing an index structure of a predistortion model table in the prior art. The LUT parameters are power-calculated from the input data to obtain corresponding table index addresses | X (n) |, and then 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 terminal of the power amplifier are corrected to obtain the DPD (X (n)) after predistortion processing.
As shown in fig. 4, it is a LUT architecture diagram corresponding to the predistortion table power calculation amplitude index. 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 use of hardware circuits for floating point operations in the FPGA wastes a lot of resources, and the working rate is also reduced, so that the current predistortion platform generally puts this part of functions into an ARM processor or a DSP, and thus, an ARM + FPGA architecture and a DSP + FPGA architecture are provided.
As mentioned in the background art, the predistortion model established by collecting signals at one rf frequency point is not necessarily applicable to other frequency points. The larger the difference in the carrier frequencies of the radio frequency signals is, the poorer the optimization effect of the predistortion is. Therefore, it is necessary to establish predistortion models for power amplifiers at different frequency points, after analyzing the coverage range of predistortion linearity optimization effect of a single frequency point on frequency, under the condition of using hardware resources as little as possible, the predistortion models are respectively established in frequency point intervals (f _1 to f _ K) at certain frequency intervals within the range of 1.6MHz to 30.0MHz of the working range of a short wave radio station, so as to ensure the effectiveness of the predistortion effect at the set frequency point, the frequency point number K can be selected according to system resources and performance requirements, and the frequency interval is 100KHz.
The digital predistortion system specifically realizes the flow: the method comprises the steps of DPD initialization, setting a path I parameter in a RAM table of a predistorter to be 1, setting a path Q parameter to be 0, judging a frequency point value to be predistorted after clock enabling, wherein a frequency point I =1 represents a first frequency point (I =1,2, 3.), and simultaneously inputting an enabling signal of a corresponding frequency point to enable an LUT parameter of the corresponding frequency point.
It should be further considered that the better the consistency of the characteristics of the power amplifier in the amplification frequency band, the wider the optimized frequency range of the predistortion, so that the gain fluctuation of the power amplifier should be reduced as much as possible in the process of designing the power amplifier, so that the characteristics of the power amplifier in the working frequency band tend to be stable. The maximum tolerance of frequency response of the short-wave radio station in the working range of 1.6 MHz-30.0 MHz is not more than 2dB. Fig. 5 is a diagram showing the measured frequency response of a 125W short-wave power amplifier. Because the short wave transmitter has a certain frequency response, the output of the obtained power amplifier needs to be further calibrated according to the frequency response curve in the working frequency range of the short wave radio station, so that the in-band unevenness of the radio station is compensated in real time in a communication state.
In order to reduce the resource consumed by actual measurement, the invention adopts a method of fitting including but not limited to a least square method in an off-line state to obtain a more subdivided power amplifier output power calibration parameter (which is to meet the requirement of a gain compensation value which may be more fine in some scenes) to compensate the in-band unevenness in a communication state in real time. The number M of the power amplifier output power calibration parameters can be selected according to system resources and performance requirements, and the frequency interval here is 1MHz.
To ensure that the calibration data in the measured state is available for each activation of each actuator, the calibration function data is stored in the ROM. When the system is started, the data space appointed by the ROM is called firstly, a gain compensation value (frequency response correction coefficient) is configured, and a gain compensation table is obtained to ensure that the gain compensation table is called when the system works normally. The invention adopts a two-dimensional index digital predistortion system structure of frequency index and amplitude index of predistortion table, and further integrates and corrects the frequency response of the short-wave power amplifier on the basis of the two-dimensional index digital predistortion system structure, and fig. 6 is a digital predistortion architecture diagram of the frequency response of the integrated and corrected short-wave power amplifier provided by the invention.
The invention provides a digital predistortion method capable of integrally correcting frequency response of a short-wave power amplifier, which specifically comprises the following steps:
1) Establishing LUT lookup tables and gain compensation lookup tables
1.1 Dividing 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, operating a digital predistortion system in a certain frequency interval to obtain output power data of the frequency interval, and feeding back the data to perform predistortion treatment to obtain an LUT lookup table of the frequency interval; repeating the steps to obtain an LUT lookup table of K frequency intervals;
the LUT lookup tables corresponding to each frequency interval have N, i.e., LUTs (1) -LUTs (N), where N may be selected according to system resources and performance requirements, where 128 is taken.
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.
After the digital baseband signal is processed by a digital predistorter, a predistortion signal is obtained; converting the predistortion signal into an analog signal through a digital-to-analog converter, and amplifying the analog signal through a power amplifier to obtain an amplified analog signal; the amplified analog signal is coupled and attenuated by a rear attenuator, converted into a digital signal by an analog-to-digital converter and transmitted to a predistortion parameter extraction module; the predistortion parameter extraction module processes the acquired digital signal and the predistortion signal to obtain predistortion parameters, namely an LUT lookup table;
1.2 While the digital predistortion system establishes an LUT lookup table of K frequency intervals, short wave frequency is divided into M continuous frequency intervals (F _1, F _2,.. Multidot.F _ M), and gain compensation lookup tables of the M frequency intervals are obtained;
the M frequency intervals divide short wave frequency according to the principle that unevenness in a digital baseband signal band 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 at the same frequency interval.
2) Digital predistortion processing through a predistortion channel
2.1 When a digital baseband signal X (n) at a certain frequency comes, the digital predistortion system multiplies the LUT lookup table index result by the input signal X (n) at the moment to obtain an amplitude predistortion signal X _ DPD (n); multiplying a gain compensation value obtained by an index gain compensation lookup table at a certain frequency point by the amplitude predistortion signal X _ DPD (n) to obtain a corrected predistortion signal Z (n);
2.1.1 Digital baseband signals X (N) corresponding to frequency points i (i is more than or equal to 1 and less than or equal to K) are subjected to power calculation to obtain corresponding amplitudes, the amplitudes are used as the addresses of LUTs of the frequency points i, indexes are carried out in LUT lookup tables LUT (1) to LUT (N) corresponding to frequency intervals f _ i where the frequency points i are located to obtain corresponding LUT values, and the corresponding LUT values are multiplied by input signals X (N) at the current moment to obtain amplitude predistortion signals X _ DPD (N);
2.1.2 In the Gain compensation lookup table corresponding to the frequency interval f _ i where the corresponding frequency point i is located, looking up the Gain compensation Gain (i) corresponding to the interval where the digital baseband signal X (n) is located of the corresponding frequency point i (i is more than or equal to 1 and less than or equal to M), and multiplying the Gain compensation with the amplitude predistortion signal X _ DPD (n) to obtain the corrected predistortion signal Z (n).
2.2 According to the relationship between the predistortion signal Z (n) output by the digital predistortion system during operation 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 input signal predistortion processing at the next moment is continued. The method specifically comprises the following steps:
2.2.1, calculating the normalized mean square error NMSE of the current input signal and the predistortion output signal dB ；
2.2.2 judging the normalized mean square error NMSE obtained by calculation dB Whether the target value is greater than a preset target value;
if yes, calculating a predistortion parameter by adopting a least square method, updating a corresponding LUT lookup table, and returning to the step 2) for predistortion treatment;
otherwise, ending the predistortion treatment of the round, and continuing to adopt the current lookup table for the predistortion treatment of the next input signal until finishing the digital predistortion treatment of the digital baseband signal.
According to the invention, the digital baseband signal of the frequency point i is subjected to frequency indexing once, so that the corresponding predistortion result and the corresponding gain compensation result can be subjected to real-time integrated compensation, and the digital predistortion signal with more stable characteristics and frequency response of the short-wave power amplifier is obtained.
All or part of the steps for implementing the above method embodiments may be implemented by hardware related to program instructions, and the program may be stored in a computer-readable storage medium, and when executed, the program performs the steps including the above method embodiments, and the storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.
Corresponding to the above method embodiments, the present application further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the steps of the external storage medium detection method are implemented.
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. A software module may reside 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.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the present invention.
Claims (8)
1. A digital predistortion method for integrated correction of the frequency response of a short wave power amplifier, comprising the steps of:
1) Establishing LUT lookup tables and gain compensation lookup tables
1.1 Taking the effectiveness of the predistortion effect of the digital baseband signal at a set frequency point as a principle, dividing the short wave frequency into K continuous frequency intervals, operating the digital predistortion system in a certain frequency interval to obtain the output power data of the frequency interval, and feeding back to perform predistortion treatment to obtain an LUT lookup table of the frequency interval; repeating the steps to obtain an LUT lookup table of K frequency intervals; the K continuous frequency intervals are f _1, f _2, a.
1.2 While the digital predistortion system establishes an LUT lookup table of K frequency intervals, short wave frequency is divided into M continuous frequency intervals to obtain gain compensation lookup tables of the M frequency intervals; the M consecutive frequency intervals are F _1, F _2,. And F _ M respectively;
the M frequency intervals divide short wave frequency according to the principle that unevenness in a digital baseband signal band can be compensated in real time in a communication state;
2) Digital predistortion processing through a predistortion channel
2.1 When a digital baseband signal X (n) at a certain frequency comes, the digital predistortion system multiplies the LUT lookup table index result by the input signal X (n) at the moment to obtain an amplitude predistortion signal X _ DPD (n); multiplying a gain compensation value obtained by an index gain compensation lookup table at a certain frequency point by the amplitude predistortion signal X _ DPD (n) to obtain a corrected predistortion signal Z (n);
2.2 According to the relationship between the predistortion signal Z (n) output by the digital predistortion system during operation 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 input signal predistortion processing at the next moment is continued until the digital predistortion processing of the digital baseband signal is completed.
2. The digital predistortion method for integrally correcting frequency response of short wave power amplifier according to claim 1, wherein the step 2.1) is specifically:
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 the address of the LUT of the frequency point i, the LUT lookup tables LUT (1) to LUT (N) corresponding to the frequency interval f _ i where the frequency point i is located are indexed to obtain a corresponding LUT value, and the corresponding LUT value is multiplied by the digital baseband signal X (N) at the current moment to obtain an amplitude predistortion signal X _ DPD (N);
2.1.2 Searching Gain compensation Gain (i) corresponding to the frequency point i in a Gain compensation lookup table corresponding to a frequency interval F _ i where the corresponding frequency point i is located, and multiplying the Gain compensation and the amplitude predistortion signal X _ DPD (n) to obtain a corrected predistortion signal Z (n).
3. The digital predistortion method for integratably correcting the frequency response of a short wave power amplifier according to claim 2, wherein:
step 2.1.1), N =128.
4. The digital predistortion method for integrally correcting frequency response of short wave power amplifier according to claim 1, wherein the step 2.2) is specifically:
2.2.1 Computing a normalized mean square error NMSE of a current digital baseband input signal and a predistorted output signal dB ；
2.2.2 ) determining the normalized mean square error NMSE dB Whether the target value is greater than a preset target value;
if yes, calculating a predistortion parameter by adopting a least square method, replacing the predistortion parameter of the corresponding LUT lookup table by the parameter, and returning to the step 2) for predistortion treatment;
otherwise, the predistortion processing of the current digital baseband input signal is finished, 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 finished.
5. The method of digital predistortion for frequency response of an integratably correctable shortwave power amplifier according to any of claims 1 to 4, characterized by:
in the step 1.1), the frequency intervals of the K continuous 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 of integratably correcting the frequency response of a short wave power amplifier according to claim 5, wherein:
in the step 1.1), the frequency interval of the K continuous frequency intervals is 100KHz;
in step 1.2), the frequency interval of the M consecutive frequency intervals is 1MHz.
7. A computer storage medium having a computer program stored thereon, characterized in that:
the computer program when executed by a processor implements the steps of the method of integratable correction of digital predistortion of the frequency response of a short wave power amplifier of claims 1-6.
8. A computer device comprising a processor, a memory coupled to the processor, and a computer program operable on the memory, wherein:
the processor, when executing the computer program, implements the steps of the method of digital predistortion of integratably correctable short wave power amplifier frequency response of claims 1-6.
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