CN103916343B - A kind of IQ disequilibrium regulating method and apparatus for WLAN devices - Google Patents
A kind of IQ disequilibrium regulating method and apparatus for WLAN devices Download PDFInfo
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- CN103916343B CN103916343B CN201210595909.7A CN201210595909A CN103916343B CN 103916343 B CN103916343 B CN 103916343B CN 201210595909 A CN201210595909 A CN 201210595909A CN 103916343 B CN103916343 B CN 103916343B
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Abstract
The invention provides a kind of method and apparatus for being corrected to IQ imbalances in WLAN devices.The device is estimated and corrected to constitute by the uneven estimations of emitter IQ and correction and receiver IQ imbalances.In order to obtain transmitter and receiver IQ amplitude mismatch and phase mismatch coefficient, the method that the device first passes through one-dimensional scanning estimates mismatch parameter, then baseband signal is input in the imbalance of amplitude and phase correction module based on the mismatch parameter for estimating, mismatch error is corrected.
Description
Technical field
A kind of IQ disequilibrium regulating method and apparatus for WLAN devices, it belongs to digital communication technology neck
Domain, is related to be corrected WLAN devices transmitter and receiver IQ imbalances.
Background technology
Wireless communication system generally by the way of inphase-quadrature modem, will complex signal be divided into that amplitude is consistent, phase just
The IQ two-way of friendship is processed.When the phase difference between the local mixer signal of same phase (I) and orthorhombic phase (Q) is not accurate 90
When spending, then IQ two-way generates phase mismatch.The amplitude mismatch of IQ two-way is turned by frequency mixer, wave filter and modulus/digital-to-analogue
What the inconsistency of parallel operation was caused.Emitter IQ width phase mismatches and receiver IQ width phase mismatches can produce image signal, cause letter
Make an uproar than declining, for the channel estimation that multi-carrier communications systems also affect mirror image subcarrier.Simultaneously in order to improve communication
Throughput communication system is currently in use more complicated modulation system, and such as 802.11n has used 64QAM and OFDM.These complexity
Modulation technique is between the same phase (I) of the direct conversion Receiver And Transmitter of this low cost and orthorhombic phase (Q) path
The susceptibility of width phase mismatch becomes unavoidable problem in design.Now eliminate during IQ unbalanced errors also become system
A required part.
It is currently, there are two classes and eliminates the unbalanced methods of IQ：First, static shift correction；2nd, dynamic calibration.Static shift correction be
The IQ mismatch parameters of transmitter and receiver are drawn in chip board test process, it is uneven that the mismatch parameter that will be measured is fixed to IQ
In weighing apparatus correction module.The advantage of the method be implement it is simple, if having the disadvantage the IQ mismatch errors of chip work one section when
Between after change, the method cannot be corrected again.Dynamic calibration refers to that transmitter and receiver IQ is lost after electricity on chip
In the parameter read-in IQ disequilibrium regulating modules estimated and will estimated with parameter.The method is excellent compared with static shift correction
If the IQ unbalanced errors that point is chip are changed after a period of operation, the method can be estimated IQ mismatches again
And correction, shortcoming be then implement it is more complicated.
The content of the invention
In order to solve the problems, such as to influence quadrature receiver dynamic range and receptivity with quadrature branch width phase mismatch,
The present invention estimates that baseband signal input is then based on the mismatch parameter by width phase mismatch parameter again using a kind of by one-dimensional scanning
The method that is processed of disequilibrium regulating module.The IQ mismatch errors of transmitter and receiver can be eliminated by the method.
The invention provides a kind of orthogonal differing in WLAN devices to transmitter and receiver IQ passages
The method and apparatus that cause property is estimated and corrected, as shown in Figure 1 and Figure 2.Emitter IQ mismatch repairs are by sine in the method
Test baseband signal passes through RF transmitting paths, Envelope Detector and LPF by emitter IQ disequilibrium regulatings module
Afterwards, the signal after ADC is sampled is stored in SRAM, is calculated signal energy and is simultaneously adjusted emitter correction baseband parameter.
After completing single pass, corresponding base band is adjusted according to the sweep limits and gradient of the width phase mismatch parameter for setting
Parameter.
The present invention estimates transmitter and receiver width phase mismatch parameter using the one-dimensional method for gradually scanning, then by base
In band signal input IQ disequilibrium regulating models, the correction of error is realized, the method comprises the following steps：
1) emitter amplitude mismatch parameter is estimated first, stationary transmitter phase mismatch parameter is one-dimensional gradually to sweep
Emitter amplitude mismatch parameter is retouched, each sweep amplitude mismatch parameter all can produce a baseband signal, look in transmitting terminal correspondence
Corresponding emitter amplitude mismatch parameter when going out baseband signal energy minimum in emitter range parameter scanning process；
2) the emitter amplitude mismatch parameter that will be estimated is fixed, then one-dimensional gradually scanning transmitter phase mismatch parameter,
Scanning phase mismatch parameter all can produce a baseband signal in transmitting terminal correspondence every time, find out transmitter phase mismatch parameter and sweep
Corresponding transmitter phase mismatch parameter when baseband signal energy is minimum during retouching；
3) the emitter amplitude mismatch parameter that will estimate, phase mismatch parameter are fixed, to receiver amplitude mismatch parameter
Estimated, fixed receiver phase mismatch parameter, one-dimensional gradually scanning radio amplitude mismatch parameter, each sweep amplitude is lost
All a baseband signal can be produced in transmitting terminal with parameter, find out baseband signal energy during receiver amplitude mismatch parameter scanning
Corresponding receiver amplitude mismatch parameter when amount is minimum；
4) the receiver amplitude mismatch parameter that will be estimated is fixed, one-dimensional gradually scanning radio phase mismatch parameter, often
Secondary scanning phase mismatch parameter all can produce a baseband signal in transmitting terminal, find out baseband signal energy in this scanning process
Corresponding receiver phase mismatch parameter when minimum, the receiver phase mismatch parameter that will be estimated is fixed；
5) by above-mentioned steps, amplitude, the amplitude of phase mismatch parameter and receiver, the phase of emitter are estimated respectively
Mismatch parameter, realizes baseband signal mismatch repair.
The degree of emitter IQ amplitudes and unbalance in phase error is wherein estimated, the degree based on institute's estimation error is sent out
Machine IQ disequilibrium regulatings are penetrated, to reduce the influence of this error；The degree of estimation receiver IQ amplitudes and unbalance in phase error,
Degree based on institute's estimation error carries out receiver IQ disequilibrium regulatings, to reduce the influence of this error；It is uneven according to IQ
The scope and precision of error estimation determine the scope and gradient of corresponding one-dimensional scanning.
Brief description of the drawings
Fig. 1 is that emitter IQ is uneven to be estimated and correction system block diagram.
Fig. 2 is that receiver IQ is uneven to be estimated and correction system block diagram.
Fig. 3 is emitter IQ disequilibrium regulating modules.
Fig. 4 is receiver IQ disequilibrium regulating modules.
Fig. 5 is the structure chart for implementing.
Specific embodiment
Emitter IQ imbalance models：
The baseband complex signal of transmitting can be expressed as：
vbb(t)=I (t)+jQ (t)
Assuming that in the case of no direct current biasing, then can be expressed as by the output signal after frequency mixer：
Gain is emitter IQ amplitude imbalance coefficients；
It is emitter IQ unbalance in phase coefficients；
Therefore, corresponding IQ mismatches baseband signal is：
The baseband signal of emitter IQ mismatches can be corrected by following emitter calibration model：
Receiver IQ imbalance models：
Radio frequency reception to signal can be expressed as：
vrf(t)=I (t) cos (ωRFt)-Q(t)sin(ωRFt)
Assuming that in the case of no direct current biasing, by the base band letter that after down coversion and low pass filter, there is IQ mismatches
Number can be expressed as：
Gain is receiver IQ amplitude imbalance coefficients；
It is receiver IQ unbalance in phase coefficients；
Receiver IQ mismatch signals can be corrected by following receiver correction module：
Based on present disclosure, IQ mismatch problems in correction WLAN devices are applied to, provide specific implementation step
Suddenly.
Emitter trimming process：
1. after the startup of emitter IQ disequilibrium regulatings process, RF switch is set, by transmitter path and Envelope
Detector is connected.Enter sinusoidal signal wave file to SRAM write by ahb bus.
2. after writing test waveform file, initial emitter amplitude mismatch and phase mismatch parameter is set.Control module
Read test wave file and sent from SRAM, in waiting the data Cun Chudao SRAM that will be received from ADC after certain hour,
After having stored, data are read.The reception signal that will be read carries out DFT computings, records corresponding signal energy.
3. emitter amplitude mismatch and phase mismatch parameter, repeat step 2 are reset according to scanning rule.
4. the signal energy that calculates in each scanning process according to storage, it is right under signal energy minimum to search out
The emitter amplitude mismatch and phase mismatch parameter answered, are updated amplitude mismatch and phase mismatch in emitter calibration model
In corresponding register, emitter correction module is by following calibration model by initial digital llCQ baseband signal：
Initially I roads signal will be multiplied by the cosine value of half phase mismatch angle and subtract initial Q road signal and be multiplied by a half-phase
Amplitude mismatch gain is multiplied by after the sine value of position mismatched angles and obtains revised digital I roadbeds band signal, by initial Q road signal
The cosine value for being multiplied by half phase mismatch angle subtracts initial I roads signal and is multiplied by the sine of half phase mismatch angle and is worth to repair
Digital Q roadbeds band signal after just.
Receiver trimming process：
1. after the startup of receiver IQ disequilibrium regulatings process, RF switch is set, transmitter path and receiver are led to
Road is connected.Enter sinusoidal signal wave file to SRAM write by ahb bus.
2. after writing test waveform file, initial receiver amplitude mismatch and phase mismatch parameter is set.Control module
Read test wave file and sent from SRAM, in waiting the data Cun Chudao SRAM that will be received from ADC after certain hour,
After having stored signal, data are read.Reception signal will be read carries out DFT computings, records corresponding signal energy.
3. receiver amplitude mismatch and phase mismatch parameter, repeat step 2 are reset according to scanning rule.
4. the signal energy that calculates in each scanning process according to storage, it is right under signal energy minimum to search out
The receiver amplitude mismatch and phase mismatch parameter answered, are updated receiver amplitude mismatch and the corresponding deposit of phase mismatch
In device, receiver correction module is by following calibration model by initial digital llCQ baseband：
I roads signal that will be initial is multiplied by the cosine value of half phase mismatch angle multiplied by be subtracted after amplitude mismatch gain
The sine that initial Q roads signal is multiplied by half phase mismatch angle is worth to revised digital I roadbeds band signal, will be initial
The cosine value that Q roads signal is multiplied by half phase mismatch angle subtracts initial I roads signal and is being multiplied by half phase mismatch angle just
String value is multiplied by obtaining revised Q roadbeds band signal after amplitude mismatch gain.
System described herein is realized by base band, the combination of RF sums.Fig. 5 is the general structure realized.
The technology of the present invention method is not limited to above-described embodiment, and other modifications of the invention and embodiment are to this area
The help of technical staff will be apparent.
Claims (2)
1. a kind of device that IQ disequilibrium regulatings are carried out for WLAN devices, the device contains MCU, disequilibrium regulating mould
Block, the loop of rf, memory module, DAC module, ADC, energy computation module and adjustment baseband parameter module, wherein：
MCU controls the startup of IQ disequilibrium regulating patterns, terminates and switch back into normal transceiver mode；IQ disequilibrium regulating patterns are opened
After dynamic, the loop of rf is switched under IQ disequilibrium regulating patterns；
Disequilibrium regulating module sets mismatch parameter, and digital IQ baseband signals are modified；
The baseband signal of emitter IQ mismatches is corrected by following emitter calibration model：
I (t) ' is the in-phase signal of emitter, and Q (t) ' is the orthogonal signalling of emitter；
Gain is emitter IQ amplitude imbalance coefficients；
It is emitter IQ unbalance in phase coefficients；
Receiver IQ mismatch signals are corrected by following receiver correction module：
I (t) ' is the in-phase signal of receiver, and Q (t) ' is the orthogonal signalling of receiver；
Gain is receiver IQ amplitude imbalance coefficients；
It is receiver IQ unbalance in phase coefficients；
Under the loop of rf is disequilibrium regulating pattern, baseband signal is processed by switching switching；
Memory module is used to store the baseband signal by after the loop of rf treatment；
Digital baseband signal is reverted to analog baseband signal by DAC module；
Analog baseband signal is sampled into digital baseband signal by ADC；
Energy computation module calculates the energy of the effective frequency of baseband signal in memory module；
Adjustment baseband parameter module is to the mismatch parameter in disequilibrium regulating module according to the result calculated in trimming process
It is adjusted；Specific Adjusted Option is as follows：
1) emitter amplitude mismatch parameter is estimated first, stationary transmitter phase mismatch parameter, one-dimensional gradually scanning hair
Machine amplitude mismatch parameter is penetrated, each sweep amplitude mismatch parameter all can produce a baseband signal, find out hair in transmitting terminal correspondence
Corresponding emitter amplitude mismatch parameter when penetrating baseband signal energy minimum in machine range parameter scanning process；
2) the emitter amplitude mismatch parameter that will be estimated is fixed, then one-dimensional gradually scanning transmitter phase mismatch parameter, every time
Scanning phase mismatch parameter all can produce a baseband signal in transmitting terminal correspondence, find out transmitter phase mismatch parameter scanned
Corresponding transmitter phase mismatch parameter when baseband signal energy is minimum in journey；
3) the emitter amplitude mismatch parameter that will estimate, phase mismatch parameter are fixed, and receiver amplitude mismatch parameter is carried out
Estimate, fixed receiver phase mismatch parameter, one-dimensional gradually scanning radio amplitude mismatch parameter, each sweep amplitude mismatch ginseng
Number all can produce a baseband signal in transmitting terminal, and baseband signal energy is most during finding out receiver amplitude mismatch parameter scanning
Hour corresponding receiver amplitude mismatch parameter；
4) the receiver amplitude mismatch parameter that will be estimated is fixed, one-dimensional gradually scanning radio phase mismatch parameter, is swept every time
Retouch phase mismatch parameter all can produce a baseband signal in transmitting terminal, and baseband signal energy is minimum in finding out this scanning process
When corresponding receiver phase mismatch parameter, the receiver phase mismatch parameter that will be estimated fixes；
5) by above-mentioned steps, the amplitude of the amplitude mismatch parameter, phase mismatch parameter and receiver of emitter is estimated respectively
Mismatch parameter, phase mismatch parameter, realize baseband signal mismatch repair；
Baseband signal by after disequilibrium regulating module, being entered in respective radio-frequency loop by DAC module, pass through by analog signal
ADC is stored in memory module after being sampled into data signal, and energy computation module calculates baseband signal phase in memory module
Frequency energy is answered, adjustment baseband parameter module is entered according to the result for calculating to the mismatch parameter in base band disequilibrium regulating module
Row adjustment.
2. a kind of method for being corrected to transmitter and receiver IQ imbalances in WLAN devices,
The baseband signal of emitter IQ mismatches is corrected by following emitter calibration model：
I (t) ' is the in-phase signal of emitter, and Q (t) ' is the orthogonal signalling of emitter；
Gain is emitter IQ amplitude imbalance coefficients；
It is emitter IQ unbalance in phase coefficients；
Receiver IQ mismatch signals are corrected by following receiver correction module：
I (t) ' is the in-phase signal of receiver, and Q (t) ' is the orthogonal signalling of receiver；
Gain is receiver IQ amplitude imbalance coefficients；
It is receiver IQ unbalance in phase coefficients；
It is applied in the device described in claim 1, it is characterised in that estimate emitter using the one-dimensional method for gradually scanning
With receiver width phase mismatch parameter, then baseband signal is input into IQ disequilibrium regulating models, realizes the correction of error, the party
Method comprises the following steps：
1) emitter amplitude mismatch parameter is estimated first, stationary transmitter phase mismatch parameter, one-dimensional gradually scanning hair
Machine amplitude mismatch parameter is penetrated, each sweep amplitude mismatch parameter all can produce a baseband signal, find out hair in transmitting terminal correspondence
Corresponding emitter amplitude mismatch parameter when penetrating baseband signal energy minimum in machine range parameter scanning process；
2) the emitter amplitude mismatch parameter that will be estimated is fixed, then one-dimensional gradually scanning transmitter phase mismatch parameter, every time
Scanning phase mismatch parameter all can produce a baseband signal in transmitting terminal correspondence, find out transmitter phase mismatch parameter scanned
Corresponding transmitter phase mismatch parameter when baseband signal energy is minimum in journey；
3) the emitter amplitude mismatch parameter that will estimate, phase mismatch parameter are fixed, and receiver amplitude mismatch parameter is carried out
Estimate, fixed receiver phase mismatch parameter, one-dimensional gradually scanning radio amplitude mismatch parameter, each sweep amplitude mismatch ginseng
Number all can produce a baseband signal in transmitting terminal, and baseband signal energy is most during finding out receiver amplitude mismatch parameter scanning
Hour corresponding receiver amplitude mismatch parameter；
4) the receiver amplitude mismatch parameter that will be estimated is fixed, one-dimensional gradually scanning radio phase mismatch parameter, is swept every time
Retouch phase mismatch parameter all can produce a baseband signal in transmitting terminal, and baseband signal energy is minimum in finding out this scanning process
When corresponding receiver phase mismatch parameter, the receiver phase mismatch parameter that will be estimated fixes；
5) by above-mentioned steps, the amplitude of the amplitude mismatch parameter, phase mismatch parameter and receiver of emitter is estimated respectively
Mismatch parameter, phase mismatch parameter, realize baseband signal mismatch repair.
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Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104219186A (en) * | 2014-09-04 | 2014-12-17 | 中国电子科技集团公司第二十九研究所 | Simulated IQ modulation error correction method based on IQ baseband signal amplitude regulation |
| CN105162533B (en) * | 2015-07-24 | 2017-10-31 | 天津大学 | Transmitter amplitude imbalance and phase imbalance measuring method |
| CN105450178B (en) * | 2015-12-29 | 2018-05-25 | 江苏星宇芯联电子科技有限公司 | A kind of mixer of recoverable IQ mismatches |
| CN106058480B (en) * | 2016-06-01 | 2019-04-19 | 西安电子工程研究所 | A kind of any polarized wave generates and calibration method |
| CN109474553B (en) * | 2018-12-06 | 2020-04-21 | 上海移芯通信科技有限公司 | Method and system for estimating signal distortion parameters of terminal transmission path |
| CN110708084B (en) * | 2019-10-15 | 2022-04-29 | 成都振芯科技股份有限公司 | Envelope detection based originating IQ correction circuit and method |
| CN110943791B (en) * | 2019-11-26 | 2022-10-14 | 北京中电华大电子设计有限责任公司 | Test platform and IQ mismatch test method for BLE radio frequency transceiver system |
| CN113079117B (en) * | 2020-01-04 | 2022-06-21 | 武汉芯泰科技有限公司 | Method and device for estimating IQ mismatch of receiving link |
| TWI774254B (en) * | 2021-03-02 | 2022-08-11 | 瑞昱半導體股份有限公司 | Wireless transceiver having in-phase quadrature-phase calibration function |
| CN113556302B (en) * | 2021-07-19 | 2023-12-05 | 上海擎昆信息科技有限公司 | IQ imbalance correction method and device for transmitter |
| CN116633456B (en) * | 2023-07-24 | 2023-09-19 | 高拓讯达(北京)微电子股份有限公司 | Calibration method and device for broadband radio frequency system signals and electronic equipment |
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| CN1848831A (en) * | 2005-03-14 | 2006-10-18 | 美国博通公司 | Apparatus and method for correcting iq imbalance |
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| US6687311B1 (en) * | 2000-02-15 | 2004-02-03 | General Instrument Corporation | Direct QAM modulator with digital feedback control and complex pre-equalization for phase and amplitude distortion |
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