CN105847198B - The IQ imbalances of OFDM-WLAN radio frequency test systems estimate and compensation method - Google Patents
The IQ imbalances of OFDM-WLAN radio frequency test systems estimate and compensation method Download PDFInfo
- Publication number
- CN105847198B CN105847198B CN201610145766.8A CN201610145766A CN105847198B CN 105847198 B CN105847198 B CN 105847198B CN 201610145766 A CN201610145766 A CN 201610145766A CN 105847198 B CN105847198 B CN 105847198B
- Authority
- CN
- China
- Prior art keywords
- channel
- sequence
- imbalances
- estimation
- compensation method
- 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.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
- H04L25/03006—Arrangements for removing intersymbol interference
- H04L25/03178—Arrangements involving sequence estimation techniques
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/0202—Channel estimation
- H04L25/0212—Channel estimation of impulse response
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/0202—Channel estimation
- H04L25/022—Channel estimation of frequency response
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
- H04L25/03006—Arrangements for removing intersymbol interference
- H04L2025/03592—Adaptation methods
- H04L2025/03598—Algorithms
- H04L2025/03611—Iterative algorithms
- H04L2025/03617—Time recursive algorithms
- H04L2025/03624—Zero-forcing
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
- H04L25/03006—Arrangements for removing intersymbol interference
- H04L2025/03592—Adaptation methods
- H04L2025/03598—Algorithms
- H04L2025/03611—Iterative algorithms
- H04L2025/03636—Algorithms using least mean square [LMS]
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Abstract
The invention discloses a kind of estimations of IQ imbalances and compensation method suitable for OFDM-WLAN radio frequency test systems, the smoothness properties for being first depending on channel impulse response obtain the rough estimate of IQ imbalance parameters using the long training sequence of WLAN signal, then according to minimum mean square error criterion, it is iterated operation using the pilot frequency information in symbol to obtain more accurate amplitude and phase error estimation and phase error, and carries out the joint equalization of IQ imbalance and channel to signal according to estimated result.The case where IQ imbalances proposed by the present invention estimation and compensation method are suitable for channel there are frequency selectivities, and it is compared to traditional LMS algorithm, only increase a small amount of operation and can be obtained the initial value for approaching steady state solution, greatly accelerate convergence speed of the algorithm, good estimation and compensation effect can also be obtained in the case where number of symbols is less, and there is very strong practicability.
Description
Technical field
The present invention relates to the transmitter IQ imbalances in OFDM-WLAN RF consistency testing systems to estimate and compensation side
Method belongs to signal processing, wireless communication field.
Background technology
IQ imbalances refer to transmitter and receiver in-phase branch and it is orthogonal between amplitude and phase mismatch.?
Ideally, the gain on the roads I and the roads Q is equal, phase strict orthogonal, but actual circuit system is difficult to accomplish above-mentioned ideal
Situation, the uneven filter between the nonideal Up/Down Conversion operation in transmitter and receiver end, the roads I and the roads Q can be in system
Middle introducing IQ is uneven.
Transceiver mostly uses classical super-heterodyne architecture in traditional communication system, and this structure has good inhibition
The performance of Image interference, but in the terminal, the factor of component size and cost is even more important, and Direct Conversion structure is exactly
Based on above need for improved super-heterodyne architecture, zero intermediate frequency part is eliminated, radiofrequency signal is direct by quadrature frequency conversion
It is converted to baseband signal.Compared to super-heterodyne architecture, Direct Conversion structure remove intermediate-frequency section and image-rejection filters from
And the volume and power consumption of equipment are substantially reduced, while the structure use can single chip integrated low-pass filtering and baseband signal power amplifier
It realizes, simplifies the design of terminal, and the structure has oneself of bigger in the transmitting and reception for realizing multiband, multi-standard
By spending, the mainstream that these advantages make Direct Conversion transreceiver enjoy huge commercial value and designed as mobile terminal,
As the good solution of OFDM terminals.But IQ imbalance problems present in super-heterodyne architecture are still present in zero
In frequency structure, and super-heterodyne architecture is compared, the IQ imbalances of Direct Conversion structure are generally more serious and are difficult to eliminate.
In an ofdm system, the unbalanced presence of IQ can introduce Image interference to cause the bit error rate of system to rise.Newly
Generation communication system tends to the modulation system using high-order for the handling capacity of lifting system, and the modulation methods of high-order make
The Image interference that system introduces IQ imbalances is more sensitive, and the unbalanced disturbances of small IQ can so that system performance is serious
Decline.So the estimation of IQ imbalances causes extensive discussion and research with compensation problem in academia.Existing algorithm is big absolutely
What part was studied is the IQ imbalance problems of receiver end, rarely has grinding towards IQ imbalance problems caused by transmitter merely
Study carefully, and the uneven performances that seriously restrict system of actually IQ caused by transmitter, it is the important finger of RF consistency test
Mark.
Invention content
Goal of the invention：For problem not deep enough to transmitter IQ imbalances in existing research, the present invention proposes a kind of
The unbalanced estimations of IQ and compensation method suitable for the transmitter of OFDM-WLAN radio frequency test systems.
Technical solution：A kind of estimation of IQ imbalances and compensation method suitable for OFDM-WLAN radio frequency test systems, including
Following step：
(1) signal received to Vector Signal Analyzer carries out serioparallel exchange, and carry out FFT transform translate the signals into
Frequency domain；
(2) training sequence for using signal carries out rough estimate to IQ imbalance parameters using the smoothness properties of channel, and disappears
It is influenced except IQ is unbalanced in channel estimation to be equalized the initial value of sequence；
(3) operation is iterated to obtain more using least mean-square error (LMS) criterion to the pilot frequency information in symbol
Accurate equalized sequence；
(4) it is uneven balanced with IQ to carry out united channel for sub-carrier and its image component.
Channel estimation results are expressed as in the step (2)：
Wherein, diag { λ } is true channel impulse response, α=cos (Δ φ)+j εTSin (Δ φ), β=εT cos
(Δ φ)+j sin (Δ φ), with amplitude and unbalance in phase parameter εTRelated to Δ φ, estimated value is respectively：
Wherein, LTS2=LTS#/ LTS, LTS are the frequency domain representation of training sequence, and subscript # indicates sequence of complex numbers conjugation
FFT transform as a result, k be subcarrier index value,For channel estimation,Indicate the real part for the number of winning the confidence,Indicate the void for the number of winning the confidence
Portion.
Preferably, eliminating the unbalanced influences of IQ in channel estimation in the step (2), the frequency domain response of channel indicates
For：
In the step (2) after obtaining the rough estimate result of IQ imbalances parameter and channel, the first of equalized sequence is set
Value is：
It is using the ART network iterative formula of LMS criterion for the pilot frequency information in symbol in the step (3)：
WhereinZ (k) indicates k-th of subcarrier of transmitting sequence, s
(k) k-th of subcarrier of reception sequence, w are indicatedkAnd wN-k+2For according to the newer equalized sequence of LMS criterion.
Specifically, the iterative process of equalizing coefficient is：
Wherein, k={ 2 ..., N/2 },WithThe equalized sequence and transmitting sequence at i moment are respectively represented,To use training sequenceK-th of pilot sub-carrier carry out ith iteration when error signal,To use training sequenceThe N-k+2 pilot sub-carrier carry out ith iteration
When error signal, uLMSFor step-length used in iterative process.
Preferably, using Normalized LMS Algorithm, iteration step length is designed as：
Wherein μstepFor step size normalization, value range is 0 < μstep< 2, | | z (i) | |2To receive the energy of signal.
Channel and the unbalanced joint equalization methods of IQ are in the step (4)：
Sub-carrier and its image component carry out joint consideration, channel are split as with the unbalanced joint equalizations of IQ multiple
The solution of 2 × 2 decoupling equations, defines k={ 2 ..., N/2 }：
Being estimated as frequency domain data can be then obtained by the way of zero forcing equalization：
Wherein δ > 0 are normalization factors to fight ГkFor ill-condition matrix the case where, I be unit battle array.
Advantageous effect：A kind of IQ imbalances estimation suitable for OFDM-WLAN radio frequency test systems disclosed by the invention with
Compensation method, the smoothness properties for being first depending on channel impulse response obtain IQ imbalances ginseng using the long training sequence of WLAN signal
Several rough estimates is iterated operation to obtain more then according to minimum mean square error criterion using the pilot frequency information in symbol
For accurate amplitude and phase error estimation and phase error, and carry out according to estimated result that IQ is uneven and the joint equalization of channel to signal.
This method is suitable for channel the case where there are frequency selectivities, and is compared to traditional LMS algorithm, only increases a small amount of fortune
Calculation can be obtained the initial value for approaching steady state solution, convergence speed of the algorithm greatly be accelerated, in the less situation of number of symbols
Under can also obtain good estimation and compensation effect, have very strong practicability.
Description of the drawings
Fig. 1 is transmitter IQ unbalanced system model schematics of the present invention；
Fig. 2 is the equivalent block diagram of transmitter IQ unbalanced system models of the present invention；
Fig. 3 is that IQ imbalances of the present invention are estimated and balanced method flow diagram；
Fig. 4 is (a) (b) planisphere comparing result figure afterwards before the signal IQ imbalance compensations modulated using 16QAM；
Fig. 5 is (a) (b) planisphere comparing result figure afterwards before the signal IQ imbalance compensations modulated using 64QAM；
Fig. 6 is the BER performance verification result figures of the method for the present invention.
Specific implementation mode
Being applied to the estimation of IQ imbalances and balanced method in WLAN the invention discloses a kind of.In order to which carry out must
The channel estimation wanted and tracking, WLAN standard IEEE 802.11a/g/n/ac provide long training sequence, and in symbol
Middle insertion pilot frequency information, the present invention for above-mentioned known array provide a kind of channel and IQ imbalances Combined estimator with it is balanced
Method.
Below by taking IEEE 802.11ac signals as an example, the method proposed in invention is carried out in conjunction with attached drawing further detailed
It describes in detail bright.
Attached drawing 1 be there are transmitter system when amplitude and unbalance in phase, within the system IQ imbalances mainly by
The clock of system causes, and in each frequency range of transmitting signal, its influence shows as constant, is referred to as the IQ unrelated with frequency
It is uneven.It is assumed that transmitting terminal amplitude caused by clock and unbalance in phase parameter are respectively εTWith Δ φ, then ideal time domain
Signal xL(t)=xI(t)+jxQ(t) after by frequency up-conversion operation, the radiofrequency signal of transmission is represented by：
xRF(t)=(1+ εT)cos(ω0T+ Δ φ) xI(t)-(1-εT)sin(ω0t-Δφ)xQ(t) (1)
Ideal receiver is by the radiofrequency signal and xLO(t)=exp (- j ω0T) it is mixed, then passes through low-pass filter
The signal after high fdrequency component is filtered out to be represented by：
Wherein：
α=cos (Δ φ)+j εTSin (Δ φ), β=εT cos(Δφ)+jsin(Δφ) (2)
The equivalent block diagram of the unbalanced Model in Time Domain of transmitter IQ is as shown in Fig. 2, OFDM symbol s=[s (1) s (2)
… s(N)]TBy IFFT operational transformations to time domain, and adds cyclic prefix to symbol head and formedIt is grasped by parallel-serial conversion
Frequency up-conversion operation is carried out by antenna after work, by the unbalanced influences of transmitter IQ, the signal of actual transmission is represented by：The length of channel finite impulse response is less than the length of cyclic prefix, therefore before receiving terminal removal cycle
After sewing, receives sequence and be represented by：
Wherein, HcFor the cyclic shift matrices of N × N sizes,For the white Gaussian noise of receiving terminal.Matrix HcCycle move
Position characteristic so that the result of its Fourier transformation is diagonal matrix, is carried out at the same time Fourier transform operation to above formula both ends, and define
Subscript # indicates the FFT transform of sequence of complex numbers conjugation as a result, its relationship between former sequence FFT transformation results is represented by：
The relationship that frequency domain receives between sequence z and former sequence s, which can be obtained, is：
Z=diag (λ) (α s+ β s#)+v (5)
Wherein, diag { λ } is true channel impulse response, and v is white Gaussian noise.
As shown in figure 3, a kind of IQ suitable for OFDM-WLAN radio frequency test systems disclosed by the embodiments of the present invention is uneven
Estimation and compensation method, mainly include the following steps：
S1：The signal received to Vector Signal Analyzer carries out serioparallel exchange, and carry out FFT transform translate the signals into
Frequency domain；
S2：IQ imbalance rough estimates：Using the training sequence of signal, using the smoothness properties of channel to IQ imbalance parameters
Rough estimate is carried out, and eliminates the unbalanced influences of IQ in channel estimation to be equalized the initial value of sequence；
S3：The uneven thin estimations of IQ：Operation is iterated to obtain more using LMS criterion to the pilot frequency information in symbol
Accurate equalized sequence, and iteration step length is normalized to ensure algorithmic statement；
S4：Joint equalization：It is uneven balanced with IQ that sub-carrier and its image component carry out united channel.
Combined estimator and compensation are carried out to channel and IQ imbalances using the structure in attached drawing 3, by subcarrier and its mirror image
It matches, then sub-carrier index value k={ 2 ..., N/2 } can define following relationship：
zk=Γksk+vk (6)
Wherein, vkFor the white Gaussian noise that channel introduces, remaining parameters is defined as follows：
The iterative formula that ART network is defined using LMS algorithm is：
Wherein wkAnd wN-k+2For according to the newer equalized sequence of LMS criterion, initialization sequence is obtained by following operation：
IEEE 802.11ac add VHT-LTF fields to carry out necessary frequency deviation and channel estimation in frame head,
The VHT-LTF of 20MHz signals is defined as：
VHTLTF28,28={ 1,1, LTFleft,0,LTFright,-1,-1} (10)
Wherein,
LTFleft={ 1,1, -1, -1,1,1, -1,1, -1,1,1,1,1,1,1, -1, -1,1,1, -1,1, -1,1,1,1,1 }
LTFright=1, -1, -1,1,1, -1,1, -1,1, -1, -1, -1, -1, -1,1,1, -1, -1,1, -1,1, -1,1,
1,1,1}
The influence for ignoring noise carries out LS channel estimations, estimated result using the long training sequence field for receiving signal
It is represented by：
Wherein, LTS2=LTS#/ LTS, wherein LTS are the frequency domain representation of training sequence.For subcarrier index value k, (k is
The forward position of LTS2 transition), have：
For coherence bandwidth due to channel much larger than being spaced between subcarrier, the frequency domain response on adjacent sub-carrier can be close
Like being equal, in addition according to LTS2Nαk+2=LTS2N-(k+1)+2Making difference to two formulas can obtain：
Amplitude in actual ofdm system and phase mismatch that value is smaller, therefore IQ imbalance parameter betas are estimated as：
Being estimated as parameter alpha can be obtained according to triangle inequality relationship：
To there are the unbalanced channel estimation results of IQ to compensate, can obtain：
Therefore after obtaining the rough estimate result of IQ imbalances parameter and channel, the initial value of equalized sequence could be provided as：
Then, it is iterated using the pilot signal in IEEE 802.11ac, IEEE 802.11ac 20MHz signals
Pilot sub-carrier index value is KPilot={ ± 7, ± 21 }, the value in each pilot tone are：
pn{ -21, -7,7,21 }={ Ψnmod4,Ψ(n+1)mod4,ψ(n+2)mod4,ψ(n+3)mod4} (18)
The linear displacement characteristic of pilot frequency information ensure that the validity of equalized sequence solution, introduce time index i in the sequence,
It enablesWithRespectively represent the equalized sequence and transmitting sequence at i moment, then it is balanced for k={ 2 ..., N/2 } to be
Several iterative process are：
WhereinTo use training sequenceK-th of pilot sub-carrier carry out ith iteration when
Error signal,To use training sequenceThe N-k+2 pilot sub-carrier carry out
Error signal when ith iteration, uLMSIt is defined as using Normalized LMS Algorithm for step-length used in iterative process：
Wherein μstepFor step size normalization, value range is 0 < μstep< 2, | | z (i) | |2To receive the energy of signal.It is logical
Cross above-mentioned iterative estimate, you can obtain IQ imbalance parameters accurate estimation, and in turn obtain channel shock response to
Carry out the frequency domain compensation of signal.Subcarrier and its image component are specially subjected to joint consideration, channel is unbalanced with IQ
Joint equalization is split as the solution of multiple 2 × 2 decoupling equations, acquires frequency domain data according to the following formula by the way of zero forcing equalization
Estimation, to be operated in the channel of the complete pair signals of frequency domain and the unbalanced joint equalizations of IQ.
There are the unbalanced systems of IQ to compensate with unbalance in phase factor pair for the amplitude estimated using this method,
Its system performance is verified, chooses in IEEE 802.11ac agreements and is modulated with using 64QAM using the MCS4 data of 16QAM modulation
MCS7 data tested, attached drawing 3 and attached drawing 4 are two groups of front and back planisphere comparative situations of sample datas compensation.It can be with
, it is evident that being influenced by IQ imbalances, the point on planisphere is distributed in discrete shape around standard planisphere point, and high-order
Modulation system is influenced bigger by IQ imbalances, and the data interlacing on various constellations point is together to cause to judge by accident.By mending
Data after repaying inhibit image component, increase the accuracy of channel estimation and equalization, effectively improve the abnormal of planisphere
Become so that the point of planisphere is collected near standard point, it is seen that the IQ imbalance frequency domain compensating methods proposed in text have non-
Often good compensation effect.
Fig. 6 shows method proposed by the present invention to bit error rate performance, and the system through overcompensation effectively improves system
Bit error rate performance, eliminate floor effect caused by IQ imbalances, and i.e. when being iterated trained using only 5 symbols
It can get good performance.
Claims (5)
1. a kind of estimation of IQ imbalances and compensation method suitable for OFDM-WLAN radio frequency test systems, it is characterised in that：Including
Following step：
(1) serioparallel exchange is carried out to the signal that Vector Signal Analyzer receives, and carries out FFT transform and translates the signals into frequency
Domain；
(2) training sequence for using signal carries out rough estimate to IQ imbalance parameters using the smoothness properties of channel, and eliminates letter
The unbalanced influences of IQ are to be equalized the initial value of sequence in road estimation；
(3) to be iterated operation using least mean-square error (LMS) criterion to the pilot frequency information in symbol updated to obtain
Equalized sequence；Wherein, it is using the ART network iterative formula of LMS criterion for the pilot frequency information in symbol：
WhereinZ (k) indicates k-th of subcarrier of transmitting sequence, s (k) tables
Show k-th of subcarrier for receiving sequence, wkAnd wN-k+2For according to the newer equalized sequence of LMS criterion；The iteration mistake of equalizing coefficient
Cheng Wei：
Wherein, k={ 2 ..., N/2 },WithThe equalized sequence and transmitting sequence at i moment are respectively represented,To use training sequenceK-th of pilot sub-carrier carry out ith iteration when error signal,To use training sequenceThe N-k+2 pilot sub-carrier carry out ith iteration
When error signal, uLMSFor step-length used in iterative process；
(4) it is uneven balanced with IQ to carry out united channel for sub-carrier and its image component；Specifically joint equalization method is：
Sub-carrier and its image component carry out joint consideration, and channel and the unbalanced joint equalizations of IQ are split as multiple 2 × 2
The solution for decoupling equation defines k={ 2 ..., N/2 }：
Being estimated as frequency domain data can be then obtained by the way of zero forcing equalization：
Wherein δ > 0 are normalization factors to fight ΓkFor ill-condition matrix the case where, I be unit battle array.
2. IQ imbalances estimation according to claim 1 and compensation method, it is characterised in that：Channel in the step (2)
Estimated result is expressed as：
Wherein, diag { λ } is true channel impulse response, α=cos (Δ φ)+j εTSin (Δ φ), β=εTcos(Δφ)+
Jsin (Δ φ), with amplitude and unbalance in phase parameter εTRelated to Δ φ, estimated value is respectively：
Wherein, LTS2=LTS#/ LTS, LTS are the frequency domain representation of training sequence, and subscript # indicates the FFT transform of sequence of complex numbers conjugation
As a result, k is subcarrier index value,For channel estimation,Indicate the real part for the number of winning the confidence,Indicate the imaginary part for the number of winning the confidence.
3. IQ imbalances estimation according to claim 2 and compensation method, it is characterised in that：It is eliminated in the step (2)
The unbalanced influences of IQ in channel estimation, the frequency domain response of channel are expressed as：
4. IQ imbalances estimation according to claim 3 and compensation method, it is characterised in that：It is being obtained in the step (2)
After taking IQ imbalances parameter and the rough estimate result of channel, the initial value that equalized sequence is arranged is：
5. IQ imbalances estimation according to claim 1 and compensation method, it is characterised in that：Using Normalized LMS Algorithm,
Iteration step length is designed as：
Wherein μstepFor step size normalization, value range is 0 < μstep< 2, | | z (i) | |2To receive the energy of signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610145766.8A CN105847198B (en) | 2016-03-15 | 2016-03-15 | The IQ imbalances of OFDM-WLAN radio frequency test systems estimate and compensation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610145766.8A CN105847198B (en) | 2016-03-15 | 2016-03-15 | The IQ imbalances of OFDM-WLAN radio frequency test systems estimate and compensation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105847198A CN105847198A (en) | 2016-08-10 |
| CN105847198B true CN105847198B (en) | 2018-11-09 |
Family
ID=56587032
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610145766.8A Active CN105847198B (en) | 2016-03-15 | 2016-03-15 | The IQ imbalances of OFDM-WLAN radio frequency test systems estimate and compensation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105847198B (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107579938B (en) * | 2017-07-26 | 2019-10-25 | 佛山市顺德区中山大学研究院 | A kind of channel equalization method of joint IQ compensation |
| CN109728856B (en) | 2017-10-27 | 2021-12-31 | 富士通株式会社 | Estimation device and compensation device for IQ imbalance of optical transmitter and electronic equipment |
| CN108123905B (en) * | 2017-12-20 | 2020-07-07 | 普联技术有限公司 | Estimation method, estimation device, estimation equipment and storage medium of IQ imbalance |
| CN108616469B (en) * | 2018-05-11 | 2020-10-02 | 东南大学 | Method and device for estimating and compensating IQ imbalance of receiving end of SC-FDE system |
| CN111786922B (en) * | 2020-06-04 | 2022-12-06 | 东南大学 | OFDM system IQ imbalance and channel joint estimation method based on NLS |
| CN112653646B (en) * | 2020-12-22 | 2023-02-17 | 上海创远仪器技术股份有限公司 | Method, system, device, processor and storage medium for time-frequency domain data conversion processing of 5G signals of vector signal analyzer platform |
| CN112888025B (en) * | 2021-01-12 | 2022-11-11 | 深圳市极致汇仪科技有限公司 | Method and system for processing received WIFI data based on extended bandwidth |
| CN114374593B (en) * | 2022-01-07 | 2023-02-28 | 上海物骐微电子有限公司 | IQ imbalance compensation method for WiFi broadband transceiving path and application |
| CN116244571A (en) * | 2023-02-08 | 2023-06-09 | 南方海洋科学与工程广东省实验室(湛江) | Orthogonal unbalance compensation method, system, device and medium |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000252946A (en) * | 1999-02-25 | 2000-09-14 | Nippon Telegr & Teleph Corp <Ntt> | Distortion compensation circuit for ofdm |
| US7346135B1 (en) * | 2002-02-13 | 2008-03-18 | Marvell International, Ltd. | Compensation for residual frequency offset, phase noise and sampling phase offset in wireless networks |
| CN101815056A (en) * | 2010-03-05 | 2010-08-25 | 华为技术有限公司 | IQ unbalanced calibration method and equipment of baseband signals in wireless communication receiving machine |
| CN103840896A (en) * | 2012-11-21 | 2014-06-04 | 特克特朗尼克公司 | Measurement of IQ imbalance in a vector modulator |
| CN104580060A (en) * | 2015-01-20 | 2015-04-29 | 重庆邮电大学 | Digital pre-distortion correcting device and method against IQ unbalance distortion |
-
2016
- 2016-03-15 CN CN201610145766.8A patent/CN105847198B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000252946A (en) * | 1999-02-25 | 2000-09-14 | Nippon Telegr & Teleph Corp <Ntt> | Distortion compensation circuit for ofdm |
| US7346135B1 (en) * | 2002-02-13 | 2008-03-18 | Marvell International, Ltd. | Compensation for residual frequency offset, phase noise and sampling phase offset in wireless networks |
| CN101815056A (en) * | 2010-03-05 | 2010-08-25 | 华为技术有限公司 | IQ unbalanced calibration method and equipment of baseband signals in wireless communication receiving machine |
| CN103840896A (en) * | 2012-11-21 | 2014-06-04 | 特克特朗尼克公司 | Measurement of IQ imbalance in a vector modulator |
| CN104580060A (en) * | 2015-01-20 | 2015-04-29 | 重庆邮电大学 | Digital pre-distortion correcting device and method against IQ unbalance distortion |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105847198A (en) | 2016-08-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105847198B (en) | The IQ imbalances of OFDM-WLAN radio frequency test systems estimate and compensation method | |
| CN104717172B (en) | IQ imbalance compensations method and apparatus in a kind of emitter | |
| CN103312640B (en) | A kind of method of joint channel estimation and IQ imbalance compensation | |
| CN101945066B (en) | Channel estimation method of OFDM/OQAM system | |
| US9537701B2 (en) | Joint estimation and compensation method of RF imperfections in LTE uplink system | |
| CN103051578B (en) | With the iteration error propagation judgement OFDM channel estimation method that ICI eliminates | |
| CN110380996B (en) | Frequency-dependent IQ imbalance compensation method in SC-FDE system | |
| CN102769599B (en) | A kind of novel signal of orthogonal frequency division multiplexing system processing method and device | |
| US20090196334A1 (en) | System and Method for In-Phase/Quadrature-Phase (I/Q) Mismatch Measurement and Compensation | |
| Zhu et al. | Blind compensation of frequency-dependent I/Q imbalance in direct conversion OFDM receivers | |
| CN108616469B (en) | Method and device for estimating and compensating IQ imbalance of receiving end of SC-FDE system | |
| CN106161304B (en) | A kind of transmitting terminal IQ imbalance compensation method of joint channel estimation | |
| CN113078966B (en) | High-precision 5G large-bandwidth signal testing method | |
| CN105162533B (en) | Transmitter amplitude imbalance and phase imbalance measuring method | |
| Cheng et al. | Joint estimation for I/Q imbalance and multipath channel in millimeter-wave SC-FDE systems | |
| CN107426121B (en) | Training sequence design and application method and device for broad sense Frequency Division Multiplexing system | |
| WO2010017064A1 (en) | Iq imbalance equalization system and method | |
| Yan et al. | Carrier frequency offset estimation and I/Q imbalance compensation for OFDM systems | |
| Yan et al. | Carrier frequency offset estimation for OFDM systems with I/Q imbalance | |
| KR100881152B1 (en) | Apparatus for compensating frequency offset and i/q imbalance for ofdm system | |
| Lu et al. | Joint transmitter and receiver IQ imbalance estimation and compensation for OFDM systems | |
| CN105227506A (en) | The I/Q unbalance compensating method of frequency selectivity ofdm communication system | |
| CN104468429B (en) | Thresholding time domain LS channel estimation method based on Noise Variance Estimation | |
| CN108540187A (en) | The method and device of non-linear multi-user mimo system performance is improved based on MMSE criterion | |
| CN106302279A (en) | FBMC system equalization method based on interference variance statistics |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |