CN114257186A - 5G millimeter wave radio frequency power amplifier based on efficient DPD predistortion algorithm - Google Patents
5G millimeter wave radio frequency power amplifier based on efficient DPD predistortion algorithm Download PDFInfo
- Publication number
- CN114257186A CN114257186A CN202210038675.XA CN202210038675A CN114257186A CN 114257186 A CN114257186 A CN 114257186A CN 202210038675 A CN202210038675 A CN 202210038675A CN 114257186 A CN114257186 A CN 114257186A
- Authority
- CN
- China
- Prior art keywords
- radio frequency
- power amplifier
- algorithm
- dpd
- millimeter wave
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000004422 calculation algorithm Methods 0.000 title claims abstract description 115
- 238000005070 sampling Methods 0.000 claims abstract description 68
- 230000005540 biological transmission Effects 0.000 claims abstract description 18
- 230000000694 effects Effects 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 9
- 238000012545 processing Methods 0.000 claims description 9
- 230000006870 function Effects 0.000 claims description 6
- 101100458289 Drosophila melanogaster msps gene Proteins 0.000 claims description 4
- 238000010606 normalization Methods 0.000 claims description 3
- 238000012795 verification Methods 0.000 description 7
- 239000000306 component Substances 0.000 description 6
- 230000008569 process Effects 0.000 description 4
- 238000004364 calculation method Methods 0.000 description 3
- 238000012937 correction Methods 0.000 description 3
- 230000009021 linear effect Effects 0.000 description 3
- 230000008054 signal transmission Effects 0.000 description 3
- 230000006399 behavior Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000012821 model calculation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
- H03F1/32—Modifications of amplifiers to reduce non-linear distortion
- H03F1/3241—Modifications of amplifiers to reduce non-linear distortion using predistortion circuits
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/189—High-frequency amplifiers, e.g. radio frequency amplifiers
- H03F3/19—High-frequency amplifiers, e.g. radio frequency amplifiers with semiconductor devices only
- H03F3/195—High-frequency amplifiers, e.g. radio frequency amplifiers with semiconductor devices only in integrated circuits
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/20—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers
- H03F3/21—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers with semiconductor devices only
- H03F3/213—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers with semiconductor devices only in integrated circuits
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- Amplifiers (AREA)
Abstract
The invention relates to the technical field of 5G millimeter wave radio frequency power amplifiers, in particular to a 5G millimeter wave radio frequency power amplifier based on a high-efficiency DPD predistortion algorithm. The invention solves the problem of nonlinear distortion of the 5G millimeter wave power amplifier, achieves the aim of improving the nonlinear distortion of the power amplifier, improves the quality of a transmission signal of a 5G millimeter wave radio frequency channel, and improves the transmission efficiency of a radio frequency channel signal, thereby achieving the purpose of well solving the problem of nonlinear distortion of the 5G millimeter wave power amplifier while reducing the sampling rate of a feedback loop.
Description
Technical Field
The invention relates to the technical field of 5G millimeter wave radio frequency power amplifiers, in particular to a 5G millimeter wave radio frequency power amplifier based on a high-efficiency DPD predistortion algorithm.
Background
The frequency band of the 5G millimeter wave has the characteristics of high frequency band, large bandwidth, good directivity and the like, the Sub6Ghz low frequency band in 5G network planning is the user experience of 5G in the scene of realizing wide coverage and high mobility, and the frequency bands of the millimeter waves G30 and G40 meet the extremely high system capacity requirement and user experience rate of 5G in a hot spot area.
The radio frequency chip in the 5G millimeter wave communication system is a very critical and core component, wherein the 5G millimeter wave radio frequency power amplifier plays a key important role in the efficient and stable transmission of 5G millimeter wave wireless signals, and particularly, the radio frequency algorithms such as peak elimination processing and digital predistortion in the radio frequency power amplifier are adopted.
Due to the fact that the coverage area is small due to the fact that the frequency of the 5G millimeter waves is high, in order to obtain larger output signal power, the power amplifier can select an operating range close to a saturation point, therefore, nonlinear distortion of the power amplifier causes new frequency components, and the new frequency components cause the problem that demodulation is difficult for in-band effective signals of a receiver.
The carrier bandwidth of the 5G millimeter waves is 400MHz-800MHz, so that a large pressure is brought to an ADC sampling chip of a radio frequency feedback channel, when the digital predistortion algorithm is used for calculating a power amplifier behavior model due to insufficient sampling bandwidth, the feedback data sampling bandwidth is insufficient, the error of a model calculation result is large, the nonlinear improvement capability of a link is limited, and the influence on the radio frequency emission index and the power consumption lifting of the 5G millimeter waves relative to Sub6G is more than 60%. The transmission power of the 5G millimeter wave radio frequency module is too low and the efficiency of the power amplifier is low, so that the radio frequency index requirement of the ultra-large bandwidth requirement of the 5G millimeter wave 800Mhz cannot be met.
Disclosure of Invention
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides a 5G millimeter wave radio frequency power amplifier based on a high-efficiency DPD pre-distortion algorithm, which solves the problem of nonlinear distortion of the 5G millimeter wave power amplifier, achieves the aim of improving the nonlinear distortion of the power amplifier, improves the quality of a transmission signal of a 5G millimeter wave radio frequency channel, and improves the transmission efficiency of a radio frequency channel signal, thereby achieving the purpose of reducing the sampling rate of a feedback loop and simultaneously still well solving the problem of nonlinear distortion of the 5G millimeter wave power amplifier.
(II) technical scheme
In order to solve the technical problems, the invention provides the following technical scheme: A5G millimeter wave radio frequency power amplifier based on a high-efficiency DPD predistortion algorithm comprises an undersampled multi-step iteration calculation predistortion algorithm formed by mutually matching two independent algorithms, a digital predistorter calibration value is calculated, and the nonlinearity of the power amplifier is improved, so that the predistortion processing performance of the 5G millimeter wave radio frequency power amplifier is improved;
one part of the algorithm is an under-sampling predistortion algorithm, the other part of the algorithm is a multi-step iteration obtaining predistortion algorithm, and the multi-step iteration obtaining predistortion algorithm is used for compensating and optimizing the nonlinearity of the power amplifier based on the under-sampling predistortion algorithm;
the under-sampling predistortion algorithm samples the radio frequency data output by the 5G millimeter wave high-frequency power amplifier at a low sampling frequency, calculates the nonlinear model parameters of the power amplifier and reduces the sampling rate of a feedback loop;
restoring the nonlinear model parameters and the input signals by the power amplifier to output signals of the power amplifier with the same effect as the power amplifier under the high sampling frequency;
carrying out digital predistortion on the power amplifier through a traditional indirect learning algorithm to realize the linearization of the power amplifier;
the multi-step iteration solving predistortion algorithm is based on an MP memory polynomial algorithm, a DPD difference value is calculated by adopting multi-time stepping inversion, and the multiple paths of data are normalized and aligned to obtain an accurate DPD value, so that the digital predistorter can better compensate the nonlinearity of the power amplifier to be optimized, and the rapid attenuation of a radio frequency signal in a high-frequency signal is reduced.
Further, the high sampling frequency is 320000msps, and the low sampling frequency is 6400 msps.
Further, the under-sampling predistortion algorithm comprises the following steps:
s1, embedding a band-limited function in the basis function of the band-limited Volttera series to enable the bandwidth of the predistortion signal to be consistent with the bandwidth of the band-limited feedback signal;
s2, simultaneously, combining the mixed superposed radio frequency feedback signals to carry out DPD predistortion algorithm modeling on the power amplifier;
s3, simplifying the under-sampled digital pre-distortion process by capturing the in-phase component or the quadrature component of the rf feedback signal using an indirect learning algorithm.
Further, the basic formula of the MP memory polynomial algorithm model is:
wherein a ismkIs a polynomial coefficient, K is an order parameter of the polynomial model, and m is a memory depth parameter of the polynomial model.
Further, the multi-step iterative pre-distortion algorithm comprises the following steps:
s1, outputting a radio frequency signal TX-1 at a digital intermediate frequency and radio frequency transmitting unit as an original radio frequency signal of a first path of PA1, and performing normalization and alignment on two groups of signals input and output by the radio frequency signals before and after PA1 to perform first iteration;
inverting by using an MP memory polynomial algorithm to give DPD predistortion, and normalizing the processed DPD data and the second path of radio frequency signal;
s2, aligning the radio frequency signals before and after the second path of PA2, performing second iteration, calculating DPD-1 data, and normalizing the DPD-1 data with the next path of radio frequency signals to obtain TX-2;
s3, aligning the radio frequency signals before and after the third path of PA3, performing third iteration, calculating DPD-2 data, and normalizing the DPD-2 data with the next path of radio frequency signal to obtain TX-3;
s4, performing a fourth iteration on the fourth path PA4, calculating DPD-3 data, and normalizing the DPD-3 data with the previous path of radio frequency signal to obtain TX-4;
after four times of iterative processing, the excellent digital predistorter is finally obtained, and the problem of rapid attenuation of 5G millimeter wave radio-frequency signals is effectively solved.
Further, the carrier bandwidth of the 5G millimeter wave is 400MHz-800 MHz.
Furthermore, the radio frequency transmission index range of four core frequency bands of the 5G millimeter wave is 24.25-52.6 GHz.
Further, radio frequency transmission indexes of four core frequency bands of the 5G millimeter wave are n257, n258, n260 and n261 respectively.
(III) advantageous effects
The invention provides a 5G millimeter wave radio frequency power amplifier based on a high-efficiency DPD predistortion algorithm, which has the following beneficial effects:
1. the invention solves the nonlinear problem of the 5G millimeter wave power amplifier, improves the sending quality of the radio frequency signal and the overall efficiency, and meets the complex characteristics of supporting 5G millimeter wave super-large working bandwidth, mixed beam forming architecture and the like, adopts undersampling multi-step iteration to solve the predistorter to improve the nonlinearity of the power amplifier, improves the transmitted signal quality of a 5G millimeter wave radio frequency channel, improves the signal transmitting efficiency of the radio frequency channel, effectively reduces the sampling bandwidth bottleneck of an ADC sampling chip, reduces the correction time of single-channel digital predistortion, and meets the multichannel characteristics of a 5G millimeter wave system.
2. The nonlinear model parameters of the power amplifier are estimated through the output signals under undersampling by utilizing the cyclostationary characteristic of radio frequency signals, the output signals of the power amplifier with the same effect as that under high sampling frequency can be recovered through the nonlinear model parameters of the power amplifier and input signals, and finally digital predistortion is carried out on the power amplifier through the traditional indirect learning algorithm to realize the linearization of the power amplifier, so that the efficiency of the algorithm is higher than that under the same sampling frequency, and the problem that a receiver is difficult to demodulate effective signals in a 5G millimeter wave high-frequency band is effectively solved.
3. According to the method, a pre-distortion algorithm is obtained through multi-step iteration, based on an MP memory polynomial algorithm, a DPD difference value is calculated through four-time stepping inversion, then four paths of data are normalized and aligned to obtain an accurate DPD value, so that the digital predistorter can better compensate the nonlinearity of a power amplifier to be optimized, and the problem of rapid attenuation of radio frequency signals in high-frequency signals is solved.
4. According to the invention, the radio frequency data output by the 5G millimeter wave high-frequency power amplifier is sampled at a low sampling frequency through an under-sampling predistortion algorithm, and the nonlinear model parameter of the power amplifier can be well calculated, so that the sampling rate of a feedback loop is reduced, and the problem of nonlinear distortion of the 5G millimeter wave power amplifier is solved.
5. The invention adopts an innovative radio frequency DPD predistortion algorithm scheme, effectively solves the problem of rapid attenuation in 5G millimeter wave radio frequency signal transmission, meets the radio frequency transmission index requirements of four core frequency bands of 5GFR2 millimeter waves (24.25-52.6 GHz) n257, n258, n260 and n261 with ultra-large bandwidth, and can be applied to 5G millimeter wave terminals and network equipment in a large scale at low cost.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:
FIG. 1 is a schematic block diagram of a four-step iterative algorithm for solving a digital predistorter according to the present invention;
fig. 2 is a schematic block diagram of DPD verification according to an exemplary embodiment of the present invention.
Detailed Description
Embodiments of the present application will be described in detail with reference to the drawings and examples, so that how to implement technical means to solve technical problems and achieve technical effects of the present application can be fully understood and implemented.
FIG. 1 is an embodiment of the present invention: the DPD predistortion algorithm comprises an undersampled multistep iteration calculation predistortion algorithm formed by mutually matching two independent algorithms, a digital predistorter calibration value is calculated, and the nonlinearity of the power amplifier is improved, so that the predistortion processing performance of the 5G millimeter wave radio frequency power amplifier is improved.
One part of the algorithm is an undersampling predistortion algorithm, the other part of the algorithm is a multi-step iteration obtaining predistortion algorithm, and the multi-step iteration obtaining predistortion algorithm is used for compensating and optimizing the nonlinearity of the power amplifier based on the undersampling predistortion algorithm.
The under-sampling predistortion algorithm samples the radio frequency data output by the 5G millimeter wave high-frequency power amplifier at a low sampling frequency, calculates the nonlinear model parameters of the power amplifier and reduces the sampling rate of a feedback loop;
restoring the nonlinear model parameters and the input signals by the power amplifier to output signals of the power amplifier with the same effect as the power amplifier under the high sampling frequency;
the power amplifier is digitally pre-distorted through a traditional indirect learning algorithm to realize the linearization of the power amplifier, and the traditional indirect learning algorithm is an existing commonly used indirect learning algorithm.
The invention solves the nonlinear problem of the 5G millimeter wave power amplifier, improves the transmission quality of radio frequency signals and the overall efficiency, and meets the complex characteristics of supporting 5G millimeter wave super-large working bandwidth, mixed beam forming architecture and the like, adopts undersampling multi-step iteration to solve the predistorter, improves the nonlinearity of the power amplifier, improves the transmitted signal quality of a 5G millimeter wave radio frequency channel, improves the signal transmission efficiency of the radio frequency channel, effectively reduces the sampling bandwidth bottleneck of an ADC sampling chip, reduces the correction time of single-channel digital predistortion, and meets the multichannel characteristics of a 5G millimeter wave system.
The multi-step iteration solving predistortion algorithm is a DPD algorithm for solving predistortion through multi-time iteration based on an MP memory polynomial model;
based on an MP memory polynomial algorithm, a DPD difference value is calculated by adopting multi-time stepping inversion, and the multi-channel data are normalized and aligned to obtain an accurate DPD value, so that the digital predistorter can better compensate the nonlinearity of the power amplifier to be optimized, and the problem of rapid attenuation of a radio frequency signal in a high-frequency signal is solved.
The nonlinear model parameters of the power amplifier are estimated through the output signals under undersampling by utilizing the cyclostationary characteristic of radio frequency signals, the output signals of the power amplifier with the same effect as that under high sampling frequency can be recovered through the nonlinear model parameters of the power amplifier and input signals, and finally digital predistortion is carried out on the power amplifier through the traditional indirect learning algorithm to realize the linearization of the power amplifier, so that the efficiency of the algorithm is higher than that under the same sampling frequency, and the problem that a receiver is difficult to demodulate effective signals in a 5G millimeter wave high-frequency band is effectively solved.
The high sampling frequency is 320000msps, the low sampling frequency is 6400msps, the normal high sampling frequency takes 50Ghz millimeter waves as an example, takes a modulation signal with a bandwidth of 50Ghz as an example, and the predistortion input signal at least needs 25Ghz bandwidth. The sampling rate of the digital-to-analog converter is slightly higher than the bandwidth value due to the roll-off factor of the filter, and if the roll-off factor is 0.28, the sampling frequency will be 250000 × 1.28 — 320000 msps;
the low sampling frequency adopted by the invention is as follows: taking a 50Ghz millimeter wave as an example, and a modulated signal with a 50Ghz bandwidth as an example, the sampling rate would be 250000 × 1.28 × 1/50-6400 msps.
The under-sampling predistortion algorithm provided by the invention samples the radio frequency data output by the 5G millimeter wave high-frequency power amplifier at low sampling frequency, calculates the nonlinear model parameter of the power amplifier and reduces the sampling rate of a feedback loop; the power amplifier recovers the nonlinear model parameters and the input signals into the output signals of the power amplifier with the same effect as the output signals of the power amplifier under the high sampling frequency, the power consumption and the cost can be reduced, and the traditional indirect learning algorithm is used for carrying out digital predistortion on the power amplifier to realize the linearization of the power amplifier, so that the sampling rate of a feedback loop is reduced, and the problem of nonlinear distortion of the 5G millimeter wave power amplifier is solved.
The undersampling predistortion algorithm comprises the following steps:
s1, embedding a band-limited function in the basis function of the band-limited Volttera series to enable the bandwidth of the predistortion signal to be consistent with the bandwidth of the band-limited feedback signal;
s2, simultaneously, combining the mixed superposed radio frequency feedback signals to carry out DPD predistortion algorithm modeling on the power amplifier;
s3, simplifying undersampling digital predistortion processing by capturing an in-phase component or an orthogonal component of a radio frequency feedback signal by using an indirect learning algorithm, sampling radio frequency data output by a 5G millimeter wave high-frequency power amplifier at a low sampling frequency, calculating nonlinear model parameters of the power amplifier very well, achieving the purposes of reducing the sampling rate of a feedback loop and solving the problem of nonlinear distortion of the 5G millimeter wave power amplifier, wherein the undersampling factor of the predistortion algorithm can reach 20 according to a simulation test verification result.
The basic formula of the MP memory polynomial algorithm model is as follows:
wherein a ismkThe DPD algorithm model is a polynomial coefficient, K is an order parameter of the polynomial model, M is a memory depth parameter of the polynomial model, and the accuracy of the model can be improved according to the memory depth M and the order K in the formula in the calculation of the predistortion conventional variable, so that the effectiveness and the accuracy of the DPD algorithm model are improved.
The multi-step iteration pre-distortion solving algorithm comprises the following steps:
s1, outputting a radio frequency signal TX-1 at a digital intermediate frequency and radio frequency transmitting unit as an original radio frequency signal of a first path of PA1, and performing normalization and alignment on two groups of signals input and output by the radio frequency signals before and after PA1 to perform first iteration;
inverting by using an MP memory polynomial algorithm to give DPD predistortion, and normalizing the processed DPD data and the second path of radio frequency signal;
s2, aligning the radio frequency signals before and after the second path of PA2, performing second iteration, calculating DPD-1 data, and normalizing the DPD-1 data with the next path of radio frequency signals to obtain TX-2;
s3, aligning the radio frequency signals before and after the third path of PA3, performing third iteration, calculating DPD-2 data, and normalizing the DPD-2 data with the next path of radio frequency signal to obtain TX-3;
s4, performing a fourth iteration on the fourth path PA4, calculating DPD-3 data, and normalizing the DPD-3 data with the previous path of radio frequency signal to obtain TX-4;
after four times of iterative processing, the excellent digital predistorter is finally obtained, and the problem of rapid attenuation of 5G millimeter wave radio-frequency signals is effectively solved.
According to the method, a pre-distortion algorithm is obtained through multi-step iteration, based on an MP memory polynomial algorithm, a DPD difference value is calculated through four-time stepping inversion, then four paths of data are normalized and aligned to obtain an accurate DPD value, so that the digital predistorter can better compensate the nonlinearity of a power amplifier to be optimized, and the problem of rapid attenuation of radio frequency signals in high-frequency signals is solved.
The predistortion algorithm comprises an under-sampling digital predistortion algorithm and a four-step iteration algorithm which are oriented to 5G millimeter wave ultra-large working bandwidth (400 + 800Mhz), so that the digital predistortion algorithm is obtained, the sampling bandwidth bottleneck of an ADC sampling chip is effectively reduced, the single-channel digital predistortion correction time is reduced, and the multi-channel characteristic of a 5G millimeter wave system is met.
The carrier bandwidth of the 5G millimeter waves is 400MHz-800MHz, the invention adopts an innovative radio frequency DPD predistortion algorithm scheme, effectively solves the problem of rapid attenuation in 5G millimeter wave radio frequency signal transmission, meets the radio frequency transmission index requirements of four core frequency bands of 5GFR2 millimeter waves (24.25-52.6 GHz) n257, n258, n260 and n261 with ultra-large bandwidth, and can be applied to 5G millimeter wave terminals and network equipment in a large scale at low cost.
Aiming at the predistortion algorithm of the radio frequency link with the 5G millimeter wave ultra-large working bandwidth, the invention adopts undersampling multistep iteration to solve the predistorter, improves the nonlinearity of the power amplifier, improves the quality of the transmitting signal of the 5G millimeter wave radio frequency channel and improves the signal transmitting efficiency of the radio frequency channel.
The radio frequency transmission index range of four core frequency bands of the 5G millimeter wave is 24.25-52.6 GHz.
The under-sampling multi-step iteration pre-distortion algorithm provided by the invention utilizes the cyclostationarity of radio frequency signals, estimates the nonlinear model parameters of the power amplifier through the output signals under-sampling, can recover the output signals of the power amplifier with the same effect as the power amplifier under high sampling frequency by the nonlinear model parameters of the power amplifier and the input signals, and finally carries out digital pre-distortion on the power amplifier through the traditional indirect learning algorithm to realize the linearization of the power amplifier, the efficiency is higher than 36% of the algorithm under the same sampling frequency, and the problem that a receiver is difficult to demodulate effective signals in a 5G millimeter wave high-frequency band is effectively solved.
Radio frequency transmission indexes of four core frequency bands of the 5G millimeter wave are n257, n258, n260 and n261 respectively.
Aiming at the radio frequency transmission index requirements of four core frequency bands of n257, n258, n260 and n261 of 5G millimeter waves (24.25-52.6 GHz), the invention adopts an under-sampling multi-iteration predistortion DPD algorithm, solves the nonlinear problem of a 5G millimeter wave power amplifier, improves the transmission quality of radio frequency signals and improves the overall efficiency.
The invention is made for the problem of nonlinearity of a power amplifier, and the solution to nonlinearity of a high-power amplifier is to use an under-sampling multi-step iteration pre-distortion algorithm, so the implementation of the invention is irrelevant to the logic structure of the power amplifier, and the power amplifier is a product in the prior art, so that the related technologies such as processing flows and output results of input signals, intermediate signals and the like in the power amplifier are the basis of the prior art, and therefore, the related problems can be specifically referred to a power amplifier and a signal processing method with the publication number of CN102118132B, which are taken as an example for convenient understanding, and thus detailed description is omitted.
Verification example
According to the figure 2, the overall realization process of the verification mode is to cascade a digital predistorter DPD with opposite characteristics at the front end of a power amplifier, so that the whole system is in a linear effect, the scheme adopts the power amplifier aiming at the high-frequency millimeter wave of 5GFR2 to perform behavior model analysis and modeling verification, obtains a basic DPD predistortion algorithm model through model inversion, then adopts an undersampling algorithm to perform model verification and model optimization, finally obtains an optimal DPD algorithm, and meets the linear amplification effect of the high-frequency millimeter wave of 5GFR 2.
The invention provides an efficient and rapidly-realized under-sampling multi-iteration pre-distortion DPD algorithm through multiple test verification, solves the nonlinear problem of the 5G millimeter wave power amplifier, improves the transmission quality of radio frequency signals and the overall efficiency, and is applied to the 5G millimeter wave radio frequency power amplifier with the signal sampling frequency of more than 400 Ghz. The DPD algorithm can cover the commercial full frequency band of 5G millimeter waves, and reaches the leading level in the industry from 24.25GHz to 52.6 GHz.
The invention improves the non-linearity problem of the power amplifier based on the DPD pre-distortion algorithm, achieves the performance of high sampling rate with low sampling rate, and recovers the non-linear model parameters and input signals to the output signals of the power amplifier with the same effect as the output signals of the power amplifier under the high sampling rate by the power amplifier, thereby realizing the linearization of the power amplifier;
the DPD predistortion algorithm is an under-sampling multi-step iteration obtaining predistortion algorithm formed by matching an under-sampling predistortion algorithm and a multi-step iteration obtaining predistortion algorithm, and meanwhile, the multi-step iteration obtaining predistortion algorithm is used for compensating and optimizing the nonlinearity of the power amplifier based on the under-sampling predistortion algorithm.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (8)
1. A5G millimeter wave radio frequency power amplifier based on a high-efficiency DPD predistortion algorithm is characterized in that the DPD predistortion algorithm comprises an undersampled multi-step iteration pre-distortion algorithm formed on the basis of mutual cooperation of two independent algorithms and a digital predistorter calibration value is obtained;
one part of the algorithm is an under-sampling predistortion algorithm, the other part of the algorithm is a multi-step iteration obtaining predistortion algorithm, and the multi-step iteration obtaining predistortion algorithm is used for compensating and optimizing the nonlinearity of the power amplifier based on the under-sampling predistortion algorithm;
the method comprises the following steps that an under-sampling predistortion algorithm samples radio frequency data output by a 5G millimeter wave high-frequency power amplifier at a low sampling frequency, and calculates nonlinear model parameters of the power amplifier;
restoring the nonlinear model parameters and the input signals by the power amplifier to output signals of the power amplifier with the same effect as the power amplifier under the high sampling frequency;
carrying out digital predistortion on the power amplifier through a traditional indirect learning algorithm to realize the linearization of the power amplifier;
the multi-step iteration solving predistortion algorithm is based on an MP memory polynomial algorithm, a DPD difference value is calculated by adopting multi-time stepping inversion, and the multi-channel data are normalized and aligned to obtain the DPD value.
2. The efficient DPD predistortion algorithm-based 5G millimeter wave radio frequency power amplifier according to claim 1, wherein: the high sampling frequency is 320000msps, and the low sampling frequency is 6400 msps.
3. The efficient DPD predistortion algorithm-based 5G millimeter wave radio frequency power amplifier according to claim 1, wherein: the undersampling predistortion algorithm comprises the following steps:
s1, embedding a band-limited function in the basis function of the band-limited Volttera series to enable the bandwidth of the predistortion signal to be consistent with the bandwidth of the band-limited feedback signal;
s2, simultaneously, combining the mixed superposed radio frequency feedback signals to carry out DPD predistortion algorithm modeling on the power amplifier;
s3, simplifying the undersampled digital predistortion processing by capturing the in-phase component or the quadrature component of the radio frequency feedback signal by applying an indirect learning algorithm.
4. The efficient DPD predistortion algorithm-based 5G millimeter wave radio frequency power amplifier according to claim 1, wherein: the basic formula of the MP memory polynomial algorithm model is as follows:
wherein a ismkIs a polynomial coefficient, K is an order parameter of the polynomial model, and m is a memory depth parameter of the polynomial model.
5. The efficient DPD predistortion algorithm-based 5G millimeter wave radio frequency power amplifier according to claim 1, wherein: the multi-step iteration pre-distortion solving algorithm comprises the following steps:
s1, outputting a radio frequency signal TX-1 at a digital intermediate frequency and radio frequency transmitting unit as an original radio frequency signal of a first path of PA1, and performing normalization and alignment on two groups of signals input and output by the radio frequency signals before and after PA1 to perform first iteration;
inverting by using an MP memory polynomial algorithm to give DPD predistortion, and normalizing the processed DPD data and the second path of radio frequency signal;
s2, aligning the radio frequency signals before and after the second path of PA2, performing second iteration, calculating DPD-1 data, and normalizing the DPD-1 data with the next path of radio frequency signals to obtain TX-2;
s3, aligning the radio frequency signals before and after the third path of PA3, performing third iteration, calculating DPD-2 data, and normalizing the DPD-2 data with the next path of radio frequency signal to obtain TX-3;
s4, performing a fourth iteration on the fourth path PA4, calculating DPD-3 data, and normalizing the DPD-3 data with the previous path of radio frequency signal to obtain TX-4;
after four times of iterative processing, the excellent digital predistorter is finally obtained, and the problem of rapid attenuation of 5G millimeter wave radio-frequency signals is effectively solved.
6. The efficient DPD predistortion algorithm-based 5G millimeter wave radio frequency power amplifier according to claim 1, wherein: the carrier bandwidth of the 5G millimeter wave is 400MHz-800 MHz.
7. The efficient DPD predistortion algorithm-based 5G millimeter wave radio frequency power amplifier according to claim 1 or 6, wherein: the radio frequency transmission index range of four core frequency bands of the 5G millimeter wave is 24.25-52.6 GHz.
8. The efficient DPD predistortion algorithm-based 5G millimeter wave radio frequency power amplifier according to claim 1 or 6, wherein: radio frequency transmission indexes of four core frequency bands of the 5G millimeter wave are n257, n258, n260 and n261 respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210038675.XA CN114257186A (en) | 2022-01-13 | 2022-01-13 | 5G millimeter wave radio frequency power amplifier based on efficient DPD predistortion algorithm |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210038675.XA CN114257186A (en) | 2022-01-13 | 2022-01-13 | 5G millimeter wave radio frequency power amplifier based on efficient DPD predistortion algorithm |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114257186A true CN114257186A (en) | 2022-03-29 |
Family
ID=80799601
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210038675.XA Pending CN114257186A (en) | 2022-01-13 | 2022-01-13 | 5G millimeter wave radio frequency power amplifier based on efficient DPD predistortion algorithm |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114257186A (en) |
-
2022
- 2022-01-13 CN CN202210038675.XA patent/CN114257186A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110915174B (en) | Correction device and correction method | |
| US9432228B2 (en) | Digital pre-distortion filter system and method | |
| US9071207B2 (en) | Predistortion of concurrent multi-band signal to compensate for PA non-linearity | |
| CN100373782C (en) | Method and apparatus using base band transformation to improve transmitter performance | |
| KR101815329B1 (en) | Modulation agnostic digital hybrid mode power amplifier system and method | |
| US7403573B2 (en) | Uncorrelated adaptive predistorter | |
| US8982995B1 (en) | Communication device and method of multipath compensation for digital predistortion linearization | |
| US8446979B1 (en) | Predistortion with integral crest-factor reduction and reduced observation bandwidth | |
| US10623049B2 (en) | Digital predistortion processing method and apparatus | |
| US9374112B2 (en) | Capture selection for digital pre-distortion adaptation and capture concatenation for frequency hopping pre-distortion adaptation | |
| CN102939716B (en) | Multi-band wideband power amplifier digital predistortion system and method | |
| Qian et al. | A general adaptive digital predistortion architecture for stand-alone RF power amplifiers | |
| CN111064439A (en) | System and method for improving short-wave digital predistortion performance | |
| Ermolaev et al. | Advanced approach for TX impairments compensation based on signal statistical analysis at the RX side | |
| Anttila et al. | Recursive learning-based joint digital predistorter for power amplifier and I/Q modulator impairments | |
| Kumar et al. | Bandlimited DPD adapted APD for 5G communication | |
| Lu et al. | In-band digital predistortion for concurrent dual-broadband phased array transmitters | |
| CN114257186A (en) | 5G millimeter wave radio frequency power amplifier based on efficient DPD predistortion algorithm | |
| KR101470817B1 (en) | Apparatus and method of predistortion of multiple nonlinear amplifiers with single feedback loop | |
| Abe et al. | Blind Post-Compensation of Tandem Nonlinearity Caused by Transmitter and Receiver | |
| CN106712728A (en) | Method for compensating power amplifier predistortion in satellite communication | |
| JPH0865352A (en) | Digital modulator | |
| Zhang et al. | A Post-Correction Method for Terahertz Nonlinear Distortion with Dual-Band Carrier Aggregation | |
| WO2024104213A1 (en) | Communication method and related device | |
| CN112703677B (en) | Signal processing method and system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |