CN109067369A - Predistortion optimization method, device and system - Google Patents
Predistortion optimization method, device and system Download PDFInfo
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- CN109067369A CN109067369A CN201810737142.4A CN201810737142A CN109067369A CN 109067369 A CN109067369 A CN 109067369A CN 201810737142 A CN201810737142 A CN 201810737142A CN 109067369 A CN109067369 A CN 109067369A
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- 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
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- 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
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- 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
- H03F3/24—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers of transmitter output stages
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F2200/00—Indexing scheme relating to amplifiers
- H03F2200/372—Noise reduction and elimination in amplifier
Abstract
The present invention relates to a kind of predistortion optimization method, include the following steps: the input signal and power amplifier feedback signal that acquire predistortion loop intermediate power amplifier；According to input signal and power amplifier feedback signal, nonlinear response estimation is carried out, obtains estimation signal；Estimation signal is carried out obtaining estimating signal except making an uproar except processing of making an uproar；Estimate that signal and input signal carry out signal recovery according to except making an uproar, the power amplifier feedback signal after being restored；The power amplifier feedback signal by the input signal of acquisition and after restoring inputs the predistortion module in the predistortion loop.Estimate that signal and input signal above-mentioned restore the power amplifier feedback signal after being restored except making an uproar by carrying out estimation signal except processing of making an uproar, and then according to what is obtained, finally according to the power amplifier feedback signal and input signal above-mentioned progress pre-distortion after recovery.Efficiently solve the problems, such as that predistortion efficiency is lower in traditional pre-distortion method, greatly improved the efficiency of predistortion.
Description
Technical field
The present invention relates to wireless communication technology fields, more particularly to a kind of predistortion optimization method, device and system.
Background technique
In modern wireless communication systems, the transmitter of higher-wattage is the highest part of energy consumption in wireless communication system,
In order to save the energy consumption of whole system, the Energy Efficiency Ratio for improving transmitter is optimal selection.And it improves quiescent point and can be improved
The Energy Efficiency Ratio of transmitter, but also due to ingoing power amplifier nonlinearity section, results in the non-linear distortion of transmitting signal.
The conventional method for solving non-linear distortion is digital pre-distortion.
In digital pre-distortion system, signal is sent and the hardware components of acquisition are known as predistortion loop, in order to guarantee number
The performance of word predistortion, predistortion loop will meet certain signal-to-noise ratio requirement.In the implementation of the present invention, invention human hair
It is existing: in the hardware design, predistortion loop can be inevitably present thermal noise, phase noise and it is spuious the problems such as.Wherein, portion
Divide noise and spuious by can further be degrading the noise of predistortion loop as signal increase together after power amplifier
Than substantially reducing the predistortion efficiency of traditional pre-distortion method.
Summary of the invention
Based on this, it is necessary to for the above problem present in traditional pre-distortion method, provide a kind of predistortion optimization
Method, a kind of predistortion optimization device and a kind of pre-distortion system.
To achieve the above object, the embodiment of the present invention uses following technical scheme:
On the one hand, the embodiment of the present invention provides a kind of predistortion optimization method, includes the following steps:
Acquire the input signal and power amplifier feedback signal of predistortion loop intermediate power amplifier；
Nonlinear response estimation is carried out according to the input signal and the power amplifier feedback signal, obtains estimation signal；
The estimation signal is carried out obtaining estimating signal except making an uproar except processing of making an uproar；
According to the input signal and described estimate that signal carries out signal recovery, power amplifier feedback letter after being restored except making an uproar
Number；
The power amplifier feedback signal by the input signal of acquisition and after restoring inputs in the predistortion loop
Predistortion module.
The nonlinear response estimation includes that least-squares estimation or least mean-square error are estimated in one of the embodiments,
Meter.
In one of the embodiments, the estimation signal obtain except processing of making an uproar except the step of estimating signal of making an uproar,
Include:
It determines the peak power point of the estimation signal, and estimates according in the setting range of the peak power point
Signal is counted, the memory depth estimated value of the predistortion loop is calculated by the first set algorithm；
If the memory depth estimated value is greater than given threshold, according in the given threshold and the setting range
The first noise threshold is calculated by the second set algorithm in the estimation signal；
The estimation signal for being lower than first noise threshold is eliminated, obtains described estimating signal except making an uproar.
In one of the embodiments, the method also includes:
If the memory depth estimated value is less than the given threshold, the estimation letter in the setting range is abandoned
Number；
The step of jumping to the input signal and power amplifier feedback signal of the acquisition predistortion loop intermediate power amplifier.
In one of the embodiments, the estimation signal obtain except processing of making an uproar except the step of estimating signal of making an uproar,
Include:
According to the estimation signal, smoothly obtain except processing of making an uproar it is described remove to make an uproar estimate signal.
In one of the embodiments, according to the estimation signal, smoothly obtain described except estimation of making an uproar except processing of making an uproar
The step of signal, comprising:
By the long smoothing windows of setting window, the estimation signal in the setting window length is smoothed, until completing
The smoothing processing of estimation each frequency point of signal obtains described estimating signal except making an uproar；The window walk of the smoothing windows a length of one
Frequency point.
In one of the embodiments, the estimation signal obtain except processing of making an uproar except the step of estimating signal of making an uproar,
Include:
Time domain conversion is carried out according to the estimation signal that the least-squares estimation obtains；
The estimation signal after being converted according to time domain carries out noise threshold calculating, obtains the second noise threshold；
The estimation signal for being lower than second noise threshold is eliminated, obtains described estimating signal except making an uproar.
On the other hand, the embodiment of the present invention also provides a kind of predistortion optimization device, comprising:
Signal acquisition module, for acquiring the input signal and power amplifier feedback signal of predistortion loop intermediate power amplifier；
Signal estimation module is estimated for carrying out nonlinear response according to the input signal and the power amplifier feedback signal
Meter obtains estimation signal；
Except module of making an uproar, for carrying out obtaining estimating signal except making an uproar except processing of making an uproar to the estimation signal；
Signal recovery module, for according to the input signal and it is described except make an uproar estimate signal carry out signal recovery, obtain
Power amplifier feedback signal after recovery；
Signal input module, the power amplifier feedback signal after the input signal and recovery for that will acquire input institute
State the predistortion module in predistortion loop.
In another aspect, the embodiment of the present invention also provides a kind of computer equipment, including memory and processor, the storage
Device is stored with computer program, and the predistortion optimization method is realized when the computer program is executed by the processor
Step.
In another aspect, the embodiment of the present invention also provides a kind of computer readable storage medium, it is stored thereon with computer journey
Sequence, when the computer program is executed by processor the step of predistortion optimization method described in realization.
In another aspect, the embodiment of the present invention also provides a kind of pre-distortion system, including predistortion module, power amplification
Device, signal acquisition circuit, nonlinear response circuit, except make an uproar device and power amplifier feedback restoring circuit；
The signal acquisition circuit is used to acquire the input signal and power amplifier feedback signal of the power amplifier, and sends
To the nonlinear response circuit；
The nonlinear response circuit is used to carry out non-linear sound according to the input signal and the power amplifier feedback signal
It should estimate, obtain estimation signal and be sent to described except device of making an uproar；
It is described to remove processing of making an uproar for carrying out to the estimation signal except device is made an uproar, it obtains removing making an uproar and estimates signal and be sent to described
Power amplifier feeds back restoring circuit；
The power amplifier feeds back restoring circuit and is used to estimate that signal and input signal progress signal are extensive except making an uproar according to described
It is multiple, the power amplifier feedback signal after being restored, and the power amplifier feedback signal by the input signal and after restoring inputs institute
State predistortion module；
The power amplifier feedback signal that the predistortion module is used for the input signal and after restoring carries out predistortion
Processing.
A technical solution in above-mentioned technical proposal has the following technical effect that
Nonlinear response is carried out by input signal to predistortion loop intermediate power amplifier and power amplifier feedback signal to estimate
Meter, and obtained estimation signal is carried out except processing of making an uproar, and then estimate signal and input signal above-mentioned except making an uproar according to what is obtained
Signal recovery is carried out, the power amplifier feedback signal after being restored, the final power amplifier feedback signal according to after obtained recovery is with before
The input signal stated carries out pre-distortion.Efficiently solve the problems, such as that predistortion efficiency is lower in traditional pre-distortion method,
The efficiency of predistortion greatly improved.
Detailed description of the invention
Fig. 1 is the applied environment figure of predistortion optimization method in one embodiment；
Fig. 2 is the flow diagram of predistortion optimization method in one embodiment；
Fig. 3 is in one embodiment except the flow diagram for processing of making an uproar；
Fig. 4 is in another embodiment except the flow diagram for processing of making an uproar；
Fig. 5 is the modular structure block diagram that predistortion optimizes device in one embodiment；
Fig. 6 is the structural block diagram of pre-distortion system in one embodiment.
Specific embodiment
It is with reference to the accompanying drawings and embodiments, right in order to which the objects, technical solutions and advantages of the application are more clearly understood
The application is further elaborated.It should be appreciated that specific embodiment described herein is only used to explain the application, not
For limiting the application.
Referring to Fig. 1, predistortion optimization method provided in an embodiment of the present invention can be applied to a kind of transmitting shown in FIG. 1
In machine 101.Transmitter 101 for transmitting signals in wireless communication system, includes predistortion module 12 and power amplifier
14.Wherein, the input signal of predistortion module 12 namely the input signal of transmitter 101 are exporting after pre-distortion
Power amplifier processing is carried out to power amplifier 14, then is output to rear class processing unit.It, can in above-mentioned conventional signal processing
To optimize unit (such as extending corresponding optimization element circuit or configuration processor in transmitter 101) by predistortion,
According to the power amplifier feedback signal that the input signal of power amplifier 14 and power amplifier 14 export, carries out nonlinear response and estimate
Meter obtains estimation signal, in turn, carries out obtaining estimating signal except making an uproar except processing of making an uproar to estimation signal, thus according to except estimation of making an uproar
Signal and input signal above-mentioned carry out signal recovery, the power amplifier feedback signal after being restored, and by input signal and recovery
Power amplifier feedback signal afterwards inputs predistortion module 12.In this way, predistortion module 12 can be according to input signal and after restoring
Power amplifier feedback signal carry out pre-distortion, and treated output signal is sent into power amplifier 14, to carry out
Subsequent signal processing.
Referring to Fig. 2, in one embodiment, providing a kind of predistortion optimization method, it is applied in Fig. 1 in this way
Transmitter 101 for be illustrated, include the following steps S12 to S20:
S12 acquires the input signal and power amplifier feedback signal of predistortion loop intermediate power amplifier.
S14 carries out nonlinear response estimation according to input signal and power amplifier feedback signal, obtains estimation signal.
It is appreciated that input signal is to be output to power amplifier 14 after the pre-distortion of predistortion module 12
Signal.Power amplifier feedback signal is the signal exported after the processing of the power amplifier of power amplifier 14.Nonlinear response estimation is pair
The signal of input calculates nonlinear response output, can be realized using the various conventional non-linear method of response calculation of this field.
Such as Fourier transformation and least square method etc..Estimation signal is the nonlinear response output letter for the predistortion loop that estimation obtains
Number, it include effective non-linear component, and to the signal components such as the unfavorable noise of predistortion, spuious.
S16 carries out obtaining estimating signal except making an uproar except processing of making an uproar to estimation signal.
It is appreciated that except processing of making an uproar is to carry out noise elimination to estimation signal obtained above, to eliminate in estimation signal
Noise and the noise signals ingredient such as spuious, such as after signal carries out power amplifier by power amplifier 14, power amplifier nonlinear response
In noise signal ingredient.Except making an uproar, processing can be filtered by the signal of conventional noises eliminations or routine various in this field
The modes such as wave are realized.
S18 estimates that signal and input signal carry out signal recovery according to except making an uproar, the power amplifier feedback signal after being restored.
S20, by the predistortion mould in the power amplifier feedback signal input predistortion loop after the input signal and recovery of acquisition
Block.
It is appreciated that signal restores in the estimation signal after eliminating noise, combined input signal, recovery to be disappeared
Except the power amplifier feedback signal after noise；The method of recovery can be but not limited to Fourier transformation conventional in the art, example
Such as FFT (Fast Fourier Transformation, Fast Fourier Transform (FFT)) or DFT (Discrete Fourier
Transform, discrete Fourier transform).
Specifically, predistortion optimization unit can be from the defeated of the output end of predistortion module 12 namely power amplifier 14
Enter and carry out signal acquisition on end, obtain required input signal, and carries out signal from the output end of power amplifier 14 and adopt
Collection, obtains required power amplifier feedback signal.The pre- input signal and power amplifier feedback signal for losing optimization unit and then basis obtains, estimates
Nonlinear response output is counted, obtains the nonlinear response output signal corresponding to input signal and power amplifier feedback signal, namely estimate
Count signal.To which the pre- optimization unit that loses can carry out obtained estimation signal obtaining the estimation after removal noise except processing of making an uproar
Signal, namely signal is estimated except making an uproar；Finally, the input signal of signal and above-mentioned acquisition is estimated according to except making an uproar, it is extensive to carry out signal
Multiple, after recovering the power amplifier feedback signal after eliminating noise, namely recovery power amplifier feedback signal.In this way, predistortion optimization is single
Member can by after obtained recovery power amplifier feedback signal and above-mentioned input signal be input to predistortion module 12 so that in advance
Distortion module 12 can carry out pre-distortion according to the power amplifier feedback signal after input signal and recovery, and be output to rear class
Processing unit is effectively reduced negative effect of the noise to the signal-to-noise ratio of entire predistortion loop, greatly improves the efficiency of predistortion.
Referring to Fig. 3, can specifically include step S162 to S166 for step S16 in one of the embodiments:
S162 determines the peak power point of estimation signal, and according to the estimation signal in the setting range of peak power point,
The memory depth estimated value of predistortion loop is calculated by the first set algorithm.
It is appreciated that the peak power point of estimation signal, namely refer to the corresponding frequency point of peak power of estimation signal, example
Such as (or peak value searching) can be retrieved by the wider peak value of application, to determine peak power point.Peak value retrieval is to signal
The effective way for carrying out peak power retrieval can quickly determine the peak power point of estimation signal.Setting range is with peak
Being worth power points is starting frequency point, until the range of signal between the frequency point of predetermined amount, namely nearby selected in peak value
Part estimate signal, setting quantity can be set according to the needs or signal processing experience of signal processing, such as be set
Fixed number measurement value is empirical value 16.
Wherein, peak value retrieval determines the peak power point of estimation signal, can be through but not limited to following processing mode, really
Make the peak power point of estimation signal:
h-pwr(n)=| h (n) |2
Wherein, h (n) indicates estimation signal；h-pwr(n)Indicate that the power of estimation signal, n indicate variable, value is greater than or waits
In 1, and it is less than or equal to signal sampling and counts.Signal sampling predistortion of counting namely refer to optimizes unit from predistortion module 12
Output end on obtain required input signal, and required power amplifier feedback letter is obtained from the output end of power amplifier 14
Number when, the sampling number that uses.
Specifically, predistortion optimization unit can carry out peak value retrieval to the estimation signal obtained, estimation signal is determined
After peak power point, according to the estimation signal near peak power point namely in above-mentioned setting range, pass through the first set algorithm
The memory depth estimated value of entire predistortion loop is calculated.
Wherein, memory depth estimated value can be calculated by following first set algorithm:
Wherein, l indicates memory depth estimated value；N_peak indicates the constant at peak power point；N indicates variable；h(n)
Indicate estimation signal；Range indicates setting quantity above-mentioned.It is appreciated that above-mentioned the first set algorithm shown can also wrap
The deformed formula of adaptability is included, such as the deformed calculation formula of the adaptability such as correction factor or variable replacement is added, as long as
It can accurately calculate to obtain required memory depth estimated value.
S164 believes if memory depth estimated value is greater than given threshold according to the estimation in given threshold and setting range
Number, the first noise threshold is calculated by the second set algorithm.
It is appreciated that given threshold is preset effective nonlinear indicator value, can rule of thumb set, such as value is
5.First noise threshold is a power threshold, for estimating the judgement of the noise contribution in signal, to carry out following step
In except making an uproar processing.Specifically, predistortion optimization unit can compare obtained memory depth estimated value with given threshold
Compared with if memory depth estimated value is greater than given threshold, in other words, the estimation signal in setting range meets effectively non-linear finger
Mark；Then predistortion optimization unit can lead to according to the estimation signal in the above-mentioned setting range for meeting effective nonlinear indicator
It crosses the second set algorithm and calculates the first noise threshold.
First noise threshold can be calculated through but not limited to following second set algorithm:
Q=h_pwr (n_peak) * K*L/l
Wherein, Q indicates the first noise threshold；H_pwr (n_peak) indicates the power of estimation signal peak power point；K table
Show empirical value constant, e.g. 0.5；L indicates above-mentioned given threshold；L indicates memory depth estimated value.Above-mentioned second shown
Set algorithm can also include the deformed noise calculation formula of adaptability, such as correction factor or variable replacement etc. is added and adapts to
The deformed noise calculation formula of property, as long as can accurately calculate to obtain the first required noise threshold.
S166 eliminates the estimation signal for being lower than the first noise threshold, obtains estimating signal except making an uproar.
Specifically, predistortion optimizes unit after obtaining the first above-mentioned noise threshold, power can be made an uproar lower than first
The estimation signal of sound threshold value is eliminated, to retain the estimation signal that power is higher than the first noise threshold, namely is obtained except estimation of making an uproar
Signal.Optionally, above-mentioned except the process of making an uproar can be realized by following algorithm:
Wherein, h_cancel (n) indicates to estimate signal except making an uproar；H (n) indicates estimation signal；Q indicates the first noise threshold.
By above-mentioned processing step S162 to S166, the noise signal ingredient in estimation signal can effectively eliminate, it is accurate and quick
It obtains estimating that signal exports except making an uproar, it is ensured that the reliability of the power amplifier feedback signal after the recovery of subsequent acquisition, it is ensured that predistortion is excellent
The high efficiency of change.
In one of the embodiments, for step S16, estimated by the memory depth that step S162 obtains predistortion loop
After evaluation, if can also specifically include the following steps:, memory depth estimated value is less than given threshold, abandons in setting range
Estimate signal；Jump to above-mentioned step S12.
Specifically, predistortion optimizes unit when the memory depth estimated value that will be obtained is compared with given threshold, sentence
Estimation signal when being less than given threshold to memory depth estimated value namely in setting range that breaks does not meet effective non-linear finger
Mark.Predistortion optimizes unit and then abandons current above-mentioned estimation signal, and jumps to above-mentioned step S12, starts a new round
Predistortion optimization processing then execute subsequent except processing of making an uproar until obtained estimated result meets effective nonlinear indicator.Such as
This can automatically abandon the estimation signal for being unsatisfactory for effective nonlinear indicator by above-mentioned processing step, and restart
New predistortion optimization process.When estimating that signal meets effective nonlinear indicator, execute automatically it is above-mentioned except processing of making an uproar,
Output estimates signal except making an uproar, the duration and flexibility ratio of enhancing predistortion optimization.
In one of the embodiments, for step S16, can also specifically include the following steps: according to estimation signal, into
Row obtains estimating signal except making an uproar smoothly except processing of making an uproar.
It is appreciated that in the present embodiment, the Signal denoising processing in the predistortion optimization method of the embodiment of the present invention removes
Outside using above-mentioned effective nonlinear indicator modes such as relatively, can also using smooth noise reduction by the way of, to estimate signal into
Row obtains estimating signal except making an uproar except processing of making an uproar.It is smooth to be handled except processing of making an uproar can be various conventional signal smoothings in this field
Technology, such as mean filter, median filtering, gaussian filtering or bilateral filtering.
Specifically, predistortion optimizes unit after obtaining above-mentioned estimation signal, it can also be by being carried out to estimation signal
The smooth mode for removing processing of making an uproar obtains estimating signal except making an uproar.Antialiasing is more mature, good reliability, can effectively mention
The reliability of high predistortion optimization, is conducive to improve predistortion efficiency.
It can specifically include following steps smoothly except the step of handling of making an uproar for above-mentioned in one of the embodiments:
By the long smoothing windows of setting window, the estimation signal in setting window length is smoothed, until completing estimation each frequency of signal
The smoothing processing of point obtains estimating signal except making an uproar.The a length of frequency point of the window walk of smoothing windows.
It is appreciated that setting window length be preset smoothing windows window it is long, can according to smoothly remove the effect made an uproar or
Experience is specifically set, it is preferred that setting window length in the present embodiment can be with value 3.The a length of smoothing windows of window walk are moved every time
Dynamic step-length, a length of frequency point of window walk preferred in this embodiment, in other words, to the estimation signal in smoothing windows
After carrying out smoothly, the mobile frequency point of smoothing windows is smooth to carry out to the estimation signal in smoothing windows after movement.
Specifically, predistortion optimization unit smoothly remove to estimation signal and be made an uproar by setting the long smoothing windows of window
Processing, output estimate signal except making an uproar.For example, being smoothed by following smoothing algorithm to estimation signal:
Wherein, H_cancel (k) indicates smoothly to estimate signal except making an uproar except the frequency domain obtained after processing of making an uproar；M indicates setting
Window is long；K0 indicates the initial point of smoothing windows,；The estimation signal of H (j) expression frequency domain；J indicates variable.
Predistortion optimization unit can set the starting point of smoothing windows to k0+1 (value of k0 is 0), namely estimation signal
Starting frequency point, to start to carry out the estimation signal being located in smoothing windows from starting frequency point smooth；It is mobile after the completion of smooth
One frequency point, then the estimation signal being located in smoothing windows is carried out smooth.In this way, continuous gliding smoothing window, to estimation signal into
Row is smooth, until k0 > N-M namely the last one frequency point of the distal point of smoothing windows arrival estimation signal, completes estimation signal
The smoothing processing of all frequency points, the estimation signal after output smoothing are to remove to make an uproar to estimate signal.By above-mentioned smoothly except the place that makes an uproar
Reason can effectively improve the reliability of predistortion optimization except good reliability of making an uproar, and be conducive to improve predistortion efficiency.
In one of the embodiments, in above-described embodiment, according to the input signal of power amplifier and power amplifier feedback letter
Number, during carrying out nonlinear response estimation, the nonlinear response estimation of use includes least-squares estimation or lowest mean square
Estimation error.
Specifically, in the present embodiment, nonlinear response estimation can use least-squares estimation, it can also be using minimum
Mean square error is estimated to obtain estimation signal.When for example, by using least-squares estimation, Ke Yiyou:
HLS(k)=Y (k)/X (k)
Wherein, HLS(k) the estimation signal of frequency domain is indicated；The power amplifier feedback signal of Y (k) expression frequency domain；X (k) indicates frequency domain
Input signal；K indicates variable, and value is greater than or equal to 1, and is less than or equal to signal sampling and counts.In this way, by the way that letter will be inputted
Number and power amplifier feedback signal be transformed into frequency domain (as sampling obtain the signal of time domain when, can carry out signal time-frequency domain above-mentioned turn
Change), using least-squares estimation can quick output estimation signal, signal processing is simple and quick, is conducive to improve predistortion optimization
The speed of processing.
In another example when using Minimum Mean Squared Error estimation, Ke Yiyou:
R=HLS(k)*(HLS(k))H
Wherein, HMMSE(k) the estimation signal of frequency domain is indicated；HLS(k) frequency domain obtained mentioned by least square method is indicated
Estimation signal；The signal-to-noise ratio of SNR expression predistortion loop；I indicates unit matrix；K indicate variable, value be greater than or equal to 1, and
It counts less than or equal to signal sampling；The input signal of X (k) expression frequency domain；The autocorrelation matrix of R expression LS channel estimation；β is indicated
Coefficient related with modulation system, can be empirical value；E expression be expectation value function, such as E (| X (k) |2) indicate X (k)
Mean power.By using Minimum Mean Squared Error estimation, also available estimation signal, and accuracy is higher, is mentioned using raising
The reliability of high predistortion optimization processing.
Referring to Fig. 4, can also specifically comprise the following steps for above-mentioned step S16 in one of the embodiments,
S161 to S165:
S161 carries out time domain conversion according to the estimation signal that least-squares estimation obtains.
It is appreciated that the estimation signal that predistortion optimization unit can also be obtained using least-squares estimation realize it is above-mentioned
Except processing of making an uproar.During the realization of above-described embodiment, it will be understood by those skilled in the art that can be to each signal according to processing
It needs, corresponding time domain is carried out by Fourier transformation or frequency domain is converted.
S163, the estimation signal after being converted according to time domain carry out noise threshold calculating, obtain the second noise threshold.
It is appreciated that the second noise threshold is also a power threshold, for estimating the judgement of the noise contribution in signal,
To carry out removing processing of making an uproar in following step.Specifically, predistortion optimization unit can also directly be believed according to the estimation of time domain
Number, the second noise threshold is calculated.Optionally, the second noise threshold can be calculated by following formula:
Q=h_pwr (n_peak) * K
Wherein, Q indicates the second noise threshold；H_pwr (n_peak) indicates the power of estimation signal peak power point；K table
Show empirical value constant, e.g. 0.5.
S165 eliminates the estimation signal for being lower than the second noise threshold, obtains estimating signal except making an uproar.
Specifically, predistortion optimizes unit after obtaining the second above-mentioned noise threshold, power can be made an uproar lower than second
The estimation signal of sound threshold value is eliminated, to retain the estimation signal that power is higher than the second noise threshold, namely is obtained except estimation of making an uproar
Signal.Optionally, above-mentioned except the process of making an uproar can also be realized by following algorithm:
Wherein, h_cancel (n) indicates to estimate signal except making an uproar；H (n) indicates estimation signal；Q indicates the second noise threshold.
By above-mentioned processing step S161 to S165, the noise signal ingredient in estimation signal can effectively eliminate, accurately and faster
Speed obtains estimating that signal exports except making an uproar, it is ensured that the reliability of the power amplifier feedback signal after the recovery of subsequent acquisition improves predistortion
The high efficiency of optimization.
In one embodiment, the predistortion optimization method in the various embodiments described above can also be applied to other kinds of
In signal handling equipment, such as the transmitter apparatus or pre-distortion of the presence above-mentioned technical problem of the invention pointed out are set
It is standby, the different citing of the embodiment of the present invention.
Referring to Fig. 5, in one embodiment, providing a kind of predistortion optimization device 100, including signal acquisition module
09, signal estimation module 11, except module 13 of making an uproar, signal recovery module 15 and signal input module 17.Signal acquisition module 09 is used
In the input signal and power amplifier feedback signal of acquisition predistortion loop intermediate power amplifier.Signal estimation module 11 is used for according to defeated
Enter signal and power amplifier feedback signal, carry out nonlinear response estimation, obtains estimation signal.Except module 13 of making an uproar is for estimation signal
It carries out obtaining estimating signal except making an uproar except processing of making an uproar.Signal recovery module 15 be used for according to except make an uproar estimate signal and input signal into
Row signal restores, the power amplifier feedback signal after being restored.Signal input module 17, input signal and recovery for that will acquire
The predistortion module in power amplifier feedback signal input predistortion loop afterwards.
It is appreciated that the specific restriction about predistortion optimization device 100 may refer to optimize above for predistortion
The restriction of method, details are not described herein.Modules in above-mentioned predistortion optimization device 100 can be fully or partially through soft
Part, hardware and combinations thereof are realized.Above-mentioned each module can be embedded in the form of hardware or independently of computer equipment processor
In, it can also be stored in a software form in the memory of computer equipment, execute the above modules in order to which processor calls
Corresponding operation.
Nonlinear response estimation is carried out to input signal and power amplifier feedback signal by above-mentioned signal estimation module 11, is obtained
To estimation signal, and then by eliminating the noise in estimation signal except module 13 of making an uproar, eventually by 15 basis of signal recovery module
What is obtained estimates signal and input signal except making an uproar, and restores the power amplifier feedback signal after being restored, thus by the power amplifier after recovery
Feedback signal and input signal are sent into predistortion module and carry out pre-distortion.It efficiently solves pre- in traditional pre-distortion method
The lower problem of distortion efficiency, greatly improved the efficiency of predistortion.
Above-mentioned predistortion optimization device 100 can also be realized in above-mentioned each embodiment in one of the embodiments,
Predistortion optimization method sub-step.
In one embodiment, it also provides one kind and provides a kind of computer equipment, which can be upper
Machine.The computer equipment may include processor, memory, network interface, display screen and the input connected by system bus
Device.Wherein, the processor of the computer equipment is for providing calculating and control ability.The memory of the computer equipment includes
Non-volatile memory medium, built-in storage.The non-volatile memory medium is stored with operating system and computer program.The memory
Reservoir provides environment for the operation of operating system and computer program in non-volatile memory medium.The net of the computer equipment
Network interface is used to communicate with external terminal by network connection.It is above-mentioned to realize when the computer program is executed by processor
Predistortion optimization method.The display screen of the computer equipment can be liquid crystal display or electric ink display screen, the calculating
The input unit of machine equipment can be the touch layer covered on display screen, be also possible to be arranged on computer equipment shell by
Key, trace ball or Trackpad can also be external keyboard, Trackpad or mouse etc..
It in one embodiment, can be with when the computer program in above-mentioned computer equipment is executed by processor
Realize the sub-step of the predistortion optimization method in above-mentioned each embodiment.
In one embodiment, it also provides one kind and provides computer readable storage medium, be stored thereon with computer journey
Sequence, the step of above-mentioned predistortion optimization method is realized when computer program is executed by processor.
Those of ordinary skill in the art will appreciate that realizing all or part of the process in the various embodiments described above method, being can
It is completed with instructing relevant hardware by computer program, the computer program can be stored in a non-volatile calculating
In machine read/write memory medium, the computer program is when being executed, it may include such as the process of above-mentioned each method embodiment.Wherein,
To any reference of memory, storage, database or other media used in each embodiment provided herein,
Including non-volatile and/or volatile memory.Nonvolatile memory may include read-only memory (ROM), programming ROM
(PROM), electrically programmable ROM (EPROM), electrically erasable ROM (EEPROM) or flash memory.Volatile memory may include
Random access memory (RAM) or external cache.By way of illustration and not limitation, RAM is available in many forms,
Such as static state RAM (SRAM), dynamic ram (DRAM), synchronous dram (SDRAM), double data rate sdram (DDRSDRAM), enhancing
Type SDRAM (ESDRAM), synchronization link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM
(RDRAM), direct memory bus dynamic ram (DRDRAM) and memory bus dynamic ram (RDRAM) etc..
In one embodiment, when the computer program in above-mentioned read/write memory medium is executed by processor, also
The sub-step of the predistortion optimization method in above-mentioned each embodiment may be implemented.
Referring to Fig. 6, in one embodiment, also providing a kind of pre-distortion system 200, including predistortion module
12, power amplifier 14, signal acquisition circuit 16, nonlinear response circuit 18, except make an uproar device 20 and power amplifier feedback restoring circuit 22.
Signal acquisition circuit 16 is used to acquire the input signal and power amplifier feedback signal of power amplifier 14, and is sent to nonlinear response
Circuit 18.Nonlinear response circuit 18 is used to carry out nonlinear response estimation according to input signal and power amplifier feedback signal, obtain
Estimation signal is simultaneously sent to except device 20 of making an uproar.Except device 20 of making an uproar to estimation signal for carrying out obtaining estimating signal except making an uproar except processing of making an uproar
And it is sent to power amplifier feedback restoring circuit 22.Power amplifier feedback restoring circuit 22 be used for according to except make an uproar estimate signal and input signal into
Row signal restores, the power amplifier feedback signal after being restored, and the power amplifier feedback signal by input signal and after restoring inputs in advance
Distortion module 12.The power amplifier feedback signal that predistortion module 12 is used for input signal and after restoring carries out pre-distortion.
It is appreciated that the predistortion optimization method in the various embodiments described above can pass through optimization element circuit or processor shape
The predistortion optimization unit of formula is realized.In the present embodiment, it can be constituted by using digital circuit or analog circuit each
A element circuit, to implement the above-mentioned optimization to traditional pre-distortion technology.
Specifically, being output to power after above-mentioned predistortion module 12 is used to carry out pre-distortion to the signal passed through
Amplifier 14.Signal acquisition circuit 16 can obtain input signal above-mentioned from the outlet side of predistortion module 12, and from function
The outlet side of rate amplifier 14 obtains power amplifier feedback signal, and is input in nonlinear response circuit 18.Signal acquisition circuit 16
It can be the digital signal samples circuit constructed by the electronic circuit technology of this field routine, electricity can also be sampled with analog signal
Road.Nonlinear response circuit 18, except making an uproar device 20 and power amplifier feedback restoring circuit 22 may each be and have patrolling for logical operation function
Collect circuit, such as various PLC programmable circuits.
Nonlinear response estimation is carried out, is obtained according to input signal and power amplifier feedback signal by above-mentioned each circuit unit
To after estimation signal, the noise in estimation signal is eliminated；And then signal and input signal are estimated except making an uproar according to what is obtained, it recovers
Power amplifier feedback signal after recovery, by the power amplifier feedback signal and input signal feeding predistortion module progress predistortion after recovery
Processing.Efficiently solve the problems, such as that predistortion efficiency is lower in traditional pre-distortion method, greatly improved the efficiency of predistortion.
In one embodiment, each circuit unit of above-mentioned pre-distortion system 200, in the process of running,
The sub-step that above-mentioned each predistortion optimization method can also be performed, further increases the efficiency of predistortion.
Each technical characteristic of embodiment described above can be combined arbitrarily, for simplicity of description, not to above-mentioned reality
It applies all possible combination of each technical characteristic in example to be all described, as long as however, the combination of these technical characteristics is not deposited
In contradiction, all should be considered as described in this specification.
The embodiments described above only express several embodiments of the present invention, and the description thereof is more specific and detailed, but simultaneously
It cannot therefore be construed as limiting the scope of the patent.It should be pointed out that coming for those of ordinary skill in the art
It says, without departing from the inventive concept of the premise, various modifications and improvements can be made, these belong to protection of the invention
Range.Therefore, the scope of protection of the patent of the invention shall be subject to the appended claims.
Claims (11)
1. a kind of predistortion optimization method, which comprises the steps of:
Acquire the input signal and power amplifier feedback signal of predistortion loop intermediate power amplifier；
Nonlinear response estimation is carried out according to the input signal and the power amplifier feedback signal, obtains estimation signal；
The estimation signal is carried out obtaining estimating signal except making an uproar except processing of making an uproar；
According to the input signal and described estimate that signal carries out signal recovery, power amplifier feedback signal after being restored except making an uproar；
The power amplifier feedback signal by the input signal of acquisition and after restoring inputs the pre- mistake in the predistortion loop
True module.
2. predistortion optimization method according to claim 1, which is characterized in that the nonlinear response estimation includes minimum
Two multiply estimation or Minimum Mean Squared Error estimation.
3. predistortion optimization method according to claim 1, which is characterized in that carry out the estimation signal except the place that makes an uproar
Reason is obtained except the step of estimating signal of making an uproar, comprising:
It determines the peak power point of the estimation signal, and is believed according to the estimation in the setting range of the peak power point
Number, the memory depth estimated value of the predistortion loop is calculated by the first set algorithm；
If the memory depth estimated value is greater than given threshold, according in the given threshold and the setting range
Estimate signal, the first noise threshold is calculated by the second set algorithm；
The estimation signal for being lower than first noise threshold is eliminated, obtains described estimating signal except making an uproar.
4. predistortion optimization method according to claim 3, which is characterized in that the method also includes:
If the memory depth estimated value is less than the given threshold, the estimation signal in the setting range is abandoned；
The step of jumping to the input signal and power amplifier feedback signal of the acquisition predistortion loop intermediate power amplifier.
5. predistortion optimization method according to claim 1, which is characterized in that carry out the estimation signal except the place that makes an uproar
Reason is obtained except the step of estimating signal of making an uproar, comprising:
According to the estimation signal, smoothly obtain except processing of making an uproar it is described remove to make an uproar estimate signal.
6. predistortion optimization method according to claim 5, which is characterized in that according to the estimation signal, carry out smooth
Except processing of making an uproar, obtain described except the step of estimating signal of making an uproar, comprising:
By the long smoothing windows of setting window, the estimation signal in the setting window length is smoothed, until described in completing
The smoothing processing for estimating each frequency point of signal obtains described estimating signal except making an uproar；The a length of frequency point of the window walk of the smoothing windows.
7. predistortion optimization method according to claim 2, which is characterized in that carry out the estimation signal except the place that makes an uproar
Reason is obtained except the step of estimating signal of making an uproar, comprising:
Time domain conversion is carried out according to the estimation signal that the least-squares estimation obtains；
The estimation signal after being converted according to time domain carries out noise threshold calculating, obtains the second noise threshold；
The estimation signal for being lower than second noise threshold is eliminated, obtains described estimating signal except making an uproar.
8. a kind of predistortion optimizes device characterized by comprising
Signal acquisition module, for acquiring the input signal and power amplifier feedback signal of predistortion loop intermediate power amplifier；
Signal estimation module obtains estimation letter for carrying out nonlinear response estimation according to input signal and power amplifier feedback signal
Number；
Except module of making an uproar, for carrying out obtaining estimating signal except making an uproar except processing of making an uproar to the estimation signal；
Signal recovery module, for according to the input signal and it is described except make an uproar estimate signal carry out signal recovery, be restored
Power amplifier feedback signal afterwards；
Signal input module, the power amplifier feedback signal input after the input signal and recovery for that will acquire are described pre-
Predistortion module in distortion loop.
9. a kind of computer equipment, including memory and processor, the memory are stored with computer program, feature exists
In realization claim 1 to 7 described in any item predistortion optimization methods when the computer program is executed by the processor
The step of.
10. a kind of computer readable storage medium, is stored thereon with computer program, which is characterized in that the computer program
The step of claim 1 to 7 described in any item predistortion optimization methods are realized when being executed by processor.
11. a kind of pre-distortion system, which is characterized in that including predistortion module, power amplifier, signal acquisition circuit,
Nonlinear response circuit, except make an uproar device and power amplifier feedback restoring circuit；
The signal acquisition circuit is used to acquire the input signal and power amplifier feedback signal of the power amplifier, and is sent to institute
State nonlinear response circuit；
The nonlinear response circuit is used to carry out nonlinear response according to the input signal and the power amplifier feedback signal and estimate
Meter obtains estimation signal and is sent to described except device of making an uproar；
It is described to remove processing of making an uproar for carrying out to the estimation signal except device is made an uproar, it obtains estimating signal except making an uproar and being sent to the power amplifier
Feed back restoring circuit；
The power amplifier feedback restoring circuit is used to estimate that signal and the input signal carry out signal recovery except making an uproar according to described, obtain
Power amplifier feedback signal after to recovery, and the power amplifier feedback signal by the input signal and after restoring inputs the pre- mistake
True module；
The power amplifier feedback signal that the predistortion module is used for the input signal and after restoring carries out pre-distortion.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6798843B1 (en) * | 1999-07-13 | 2004-09-28 | Pmc-Sierra, Inc. | Wideband digital predistortion linearizer for nonlinear amplifiers |
| US20060012427A1 (en) * | 2004-07-14 | 2006-01-19 | Raytheon Company | Estimating power amplifier non-linearity in accordance with memory depth |
| CN101040502A (en) * | 2004-01-21 | 2007-09-19 | 电力波技术公司 | Wideband enhanced digital injection predistortion system and method |
| CN102487367A (en) * | 2010-12-02 | 2012-06-06 | 中国科学院微电子研究所 | Adaptive amplifying digital baseband pre-distortion method |
| KR101204964B1 (en) * | 2011-07-20 | 2012-11-27 | 한국과학기술원 | Predistortion apparatus and method for linearizing the local oscillator coupling effect and the power amplifier nonlinearity |
| CN102970262A (en) * | 2012-11-16 | 2013-03-13 | 华南理工大学 | Method for improving digital pre-distortion stability |
-
2018
- 2018-07-06 CN CN201810737142.4A patent/CN109067369B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6798843B1 (en) * | 1999-07-13 | 2004-09-28 | Pmc-Sierra, Inc. | Wideband digital predistortion linearizer for nonlinear amplifiers |
| CN101040502A (en) * | 2004-01-21 | 2007-09-19 | 电力波技术公司 | Wideband enhanced digital injection predistortion system and method |
| US20060012427A1 (en) * | 2004-07-14 | 2006-01-19 | Raytheon Company | Estimating power amplifier non-linearity in accordance with memory depth |
| CN102487367A (en) * | 2010-12-02 | 2012-06-06 | 中国科学院微电子研究所 | Adaptive amplifying digital baseband pre-distortion method |
| KR101204964B1 (en) * | 2011-07-20 | 2012-11-27 | 한국과학기술원 | Predistortion apparatus and method for linearizing the local oscillator coupling effect and the power amplifier nonlinearity |
| CN102970262A (en) * | 2012-11-16 | 2013-03-13 | 华南理工大学 | Method for improving digital pre-distortion stability |
Non-Patent Citations (2)
| Title |
|---|
| JIWOO KIM: "A new architecture for frequency-selective digital predistortion linearization for RF power amplifiers", 《2012 IEEE/MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST》 * |
| 张珅: "OFDM 系统功率放大器有记忆自适应预失真研究", 《电视技术》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114422318A (en) * | 2021-12-31 | 2022-04-29 | 北京无线电计量测试研究所 | Signal predistortion system response estimation method, device and system |
| CN114422318B (en) * | 2021-12-31 | 2024-03-29 | 北京无线电计量测试研究所 | System response estimation method, device and system for signal predistortion |
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