CN106534030B - A kind of channel estimation methods based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system - Google Patents
A kind of channel estimation methods based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system Download PDFInfo
- Publication number
- CN106534030B CN106534030B CN201611074345.7A CN201611074345A CN106534030B CN 106534030 B CN106534030 B CN 106534030B CN 201611074345 A CN201611074345 A CN 201611074345A CN 106534030 B CN106534030 B CN 106534030B
- Authority
- CN
- China
- Prior art keywords
- matrix
- pilot
- training sequence
- channel estimation
- channel
- 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
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
- H04L27/2601—Multicarrier modulation systems
- H04L27/2602—Signal structure
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/0413—MIMO systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/0413—MIMO systems
- H04B7/0456—Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
-
- 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
- H04L25/024—Channel estimation channel estimation algorithms
- H04L25/0242—Channel estimation channel estimation algorithms using matrix methods
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
- H04L27/2601—Multicarrier modulation systems
- H04L27/2647—Arrangements specific to the receiver only
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L5/00—Arrangements affording multiple use of the transmission path
- H04L5/003—Arrangements for allocating sub-channels of the transmission path
- H04L5/0048—Allocation of pilot signals, i.e. of signals known to the receiver
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Power Engineering (AREA)
- Radio Transmission System (AREA)
Abstract
The invention discloses a kind of channel estimation methods based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system, are related to field of communication technology.This method are as follows: firstly, being introduced into the channel information that long training field in lead code estimates training sequence after receiving end is demodulated by fft algorithm channel, using weighting matrix improvement channel information, which can be directly as channel value at data in this subcarrier；Secondly, going cyclic shift to restore above-mentioned data；Finally, estimating pilot channel by receiving signal at local pilot value and pilot tone, frequency shift (FS) and the influence of phase noise are further eliminated.The present invention completes channel estimation and receives signaling protein14-3-3 to operate using training sequence, weighting matrix and pilot value, avoid the big feature of training sequence channel estimation errors, realize the method that training sequence, weighting matrix and pilot distribution formula combine, channel estimation errors are reduced, to realize that the reception of multiple antennas ofdm system of 802.11n provides a kind of simple and efficient solution.
Description
Technical field
The present invention relates to one kind of mobile communication technology more particularly to mobile communication to be based on 802.11n multiple antennas OFDM system
The channel estimation methods of joint training sequence and pilot tone in system.
Background technique
Multiple antennas OFDM (Orthogonal Frequency Division Multiplexing, orthogonal frequency division multiplexing) system
Transmission rate is higher in system, and accurate demodulation is the guarantee of transmission quality.And can receiver accurately demodulate, and be unable to do without accurate
CSI (Channel State Information, channel state information) and detection.Channel estimation is by the channel of wireless channel
Impulse response estimates, and is the basis detected and demodulated.High performance channel estimation methods, which can use, to be estimated
Channel information by the data convert of transmission, then be decoded.
MIMO (Multiple Input Multiple Output, multiple-input and multiple-output) antenna system can provide multiple
Independent channel, under certain condition, can with signaling channel capacity with the increase of antenna number linear increase.OFDM is contrary frequency
The effective technology of Selective intensity, former channel is converted to multiple parallel flat faded sub-channels by it.IEEE 802.11n is used
The multiple antennas ofdm system transmission link of Space Time Coding, brings the wireless local area network (WLAN) system of high-throughput.
Currently, indirect mappers or spatial spread technology also be unable to do without accurate channel parameter and estimate in 802.11n standard
Meter.And the characteristics of communication system receiver equilibrium based on OFDM technology can use training sequence in time domain frame structure,
It is used by many communication standards, but is difficult to obtain preferable compromise in terms of arithmetic accuracy and complexity, often had higher
The algorithm of precision has a biggish computation complexity, and performance is not but in multiple antennas ofdm system for the lower algorithm of computation complexity
It is too ideal.Since more antennas receive data simultaneously, in low signal-to-noise ratio, also brings along and interfere between multiple antennas.For
The channel estimation methods of 802.11n multiple antennas, it has been suggested that it is some about 802.11n in receiving end multi-antenna channel estimation side
Case, such as document (Robust Channel Estimation for 802.11n (MIMO-OFDM) Systems, Effect of
Carrier Frequency Offset on Channel Estimation for SISO/MIMO-OFDM Systems) in
To data after synchronizing, discuss CFO (Carrier Frequency Offset, carrier frequency shift) to the shadow of channel estimation
It rings, proposes channel estimation methods, be not additionally added merely with HT (Hight Throughput, high-throughput) regional training sequence low
Handling capacity training sequence, document has been fully considered in 2T-1R, also improves equalizing coefficient.But if in 40MHz bandwidth and
In the case where 4 spatial flows, literature method uses the carrier number of low training sequence of handling up with regard to undesirable, and calculation amount
It is larger.
Summary of the invention
Technical problem to be solved by the invention is to provide a kind of simple and efficient, and it is suitable for being based on 802.11n more days
The channel estimation methods of joint training sequence and pilot tone in line ofdm system, be it is a kind of in order to solve channel errors minimum estimate
Meter method, while in order to realize that the transmission signal of transmitting terminal is accurately restored in receiving end in wireless communication system, the program can divide
From the interference between the mutiple antennas of receiving end, the operation independent between inverse process corresponding with each forward direction process of transmitting terminal is realized.
Design of the invention is as follows, and signal extracts the long Sequence of signal HT, use local ginseng after channel demodulates
The long training sequence for examining long training sequence and receiving end carries out related operation.In the case where not considering noise situations, this method is mainly sharp
Orthogonal mapping matrix and fourier matrix are introduced with LS (Least Square, least square) channel estimation method, is obtained k-th
The channel frequency response estimated value of subchannel:Wherein i=1,2 ...
.NRXIndicate cyclic shift, NRXIndicate receiving antenna quantity, ykData after indicating the demodulation of channel receiving end, HTLTFKFor local
With reference to high-throughput long training sequence, Δ F is sub-carrier frequencies interval,For cyclic shift.This is one based on training sequence
Estimation, make it possible channel estimation in multiple antennas.Signal is inserted into fixed subcarrier conduct in transmitting terminal spatial flow
Pilot tone, in order to avoid the influence of noise, increases channel estimation accuracy after the channel estimation of above-mentioned long training sequence,
Receiving end obtains a channel state information using pilot tone again, and main purpose is that noise reduction as much as possible recovers transmission signal.
In consideration of it, the present invention adopts the following technical scheme: a kind of based on joint training in 802.11n multiple antennas ofdm system
The channel estimation methods of sequence and pilot tone, comprising the following steps:
A, after receiving end signal is demodulated, its high-throughput region is extracted, is frequency-region signal through N point FFT transform, then into
Row serial to parallel conversion.
B, the signal after serial to parallel conversion is subjected to space reflection, is sequentially mapped to empty time stream.
C, it will be mapped to the signal removal cyclic shift delay of empty time stream.
D, step C treated signal utilizes the reception signal at local reference pilot value and pilot tone to carry out pilot channel
Estimation calculates the channel response matrix at pilot tone moment
Further, the step of space reflection described in step B are as follows:
B1, it extracts locally with reference to the corresponding empty time stream numbers matrix of high-throughput long training sequence generation:Wherein NSTSFor empty time stream quantity, HH is empty time stream numbers matrix, and HTLTF indicates this
Ground refers to high-throughput long training sequence.
B2, the long training matrix of high-throughput and orthogonal mapping matrix P are referred to by localHTLTFIt is multiplied and generates HT-LTF matrix；
HT-LTF indicates the local high-throughput long training sequence that refers to multiplied by the matrix of consequence after orthogonal mapping matrix.
HHT-LTFFor the long training matrix of high-throughput after orthogonal mapping,Represent orthogonal mapping matrix n-thSTS
Row n column element (willIt is abbreviated as [P]1,1Deng), nSTS=0,1 ..., NSTS, NSTSFor empty time stream quantity, n=0,
1,…,NHTLTF, NHTLTFIndicate high-throughput long training sequence number in a frame.
B3, HT-LTF matrix is subjected to cyclic shift.Cyclic shift is with reference to 802.11n multiple antennas ofdm system transmitting terminal
Empty time stream processing.
B4, the matrix of step B3 cyclic shift is multiplied with a fixed weighting matrix Q, expands to NRXDimensional vector.
B5, formula is calledExtend NRXIt is that dimensional vector and step A are obtained and
Row vector long training sequence, which does corresponding matrix inversion by above-mentioned formula, to be changed, and channel response matrix H is obtained.
Specifically, the fixed weighting matrix Q isWherein N=NSTS+
NESS,NESSRepresent extending space stream quantity, NSTSRepresent empty time stream quantity.Wherein HTLTFkIt is expressed as local with reference to high-throughput
Long training sequence, Q indicate fixed weighting matrix, and k is subcarrier index value, ykData after indicating the demodulation of channel receiving end, Δ F are
Sub-carrier frequencies interval,For cyclic shift, m=1,2 ... .NRX, NRXIndicate receiving antenna quantity,n
=1,2 ... .N.
In a specific embodiment of the present invention, the pilot channel estimation includes:
D1, the pilot value for extracting each empty time stream；
D2, the pilot value that each symbol is calculated according to the symbolic number complementation in each empty time stream；
D3, pilot value described in step D2 multiplied by the polarity sequence of pilot sub-carrier
D4, pilot correlation, dematrix equation are based onFind out channel response matrixIndicate pilot tone letter
Reception signal behind road,Indicate reference pilot value, wherein xi,j,nIt is j-th of transmitting antenna
I-th of pilot value in n symbol.
The present invention introduces orthogonal mapping matrix and fourier matrix in multi-aerial receiver, completes channel equalization and hair
The planisphere for the number of delivering letters restores, and in conjunction with processes such as Time and Frequency Synchronization, OFDM demodulations, realizes and be unified in the channel estimation of MIMO processing
Method.This method is suitable for the reception scheme of WLAN 802.11n signal.The reception scheme realizes and multiple antennas OFDM
Independence between the corresponding inverse process of each positive process of system transmitting terminal with separate, reduce the multiple antennas OFDM system of 802.11n
System receives the realization difficulty of signal.
Detailed description of the invention
Fig. 1 is the frame structure diagram of 802.11n standard HT mode；
Fig. 2 is the data portion receiving end structure chart of 802.11n standard HT mode；
Fig. 3 is that the estimation of 802.11n signaling channel receives flow chart.
Specific embodiment
Under the multiple antennas ofdm signal demodulation scheme of 802.11n, combines long training sequence and pilot tone completes channel jointly
The function of estimation, first signal are demodulated, and secondly demodulated signal is by after serial to parallel conversion, serial signal being converted into believing parallel
Number, it is sequentially sent to empty time stream by signal is transmitted using space reflection, is removed CSD.Space reflection is exactly that receives link is reflected
It is mapped to empty time stream, the channel estimation of 802.11n is in frequency-domain calculations, and tentatively reduction sends signal during space reflection.
As shown in Figure 1 it is the frame structure diagram of 802.11n standard HT mode, includes poor throughput and high-throughput training sequence
Column, channel estimation methods of the invention utilize the high-throughput long training sequence in frame structure.
The data for being illustrated in figure 2 802.11n standard HT mode are mapped to empty time stream multiple antennas recipient from receives link
Case figure, after the demodulated equal operation of receives link, complex-valued data is mapped to empty time stream by serial to parallel conversion, in empty time stream into
Capable channel estimation twice.
In method of the invention, two kinds of algorithms, the i.e. channel estimation method and pilot channel estimation of training sequence are contained
Algorithm, Fig. 2 illustrate the enforcing location of channel estimation twice, and specific implementation step is in Fig. 3.
Be illustrated in figure 3 802.11n combined signal training sequence and pilot-based channel estimation method schematic diagram, specifically include with
Lower processing step:
Step 1, signal is by translating the signals into as frequency-region signal after N point FFT.
Step 2, serial signal is converted into parallel signal, signal is successively transmitted as unit of symbol.
Step 3, the frequency-region signal of receives link is mapped to empty time stream.
Following steps specifically describe space reflection implementation process.
Step 31, locally with reference to HTLTF, (Hight Throughput Long Training Field, height are handled up for extraction
Measure long training sequence) generate corresponding empty time stream numbers matrix:
Wherein NSTSFor empty time stream quantity, HH indicates high-throughput in empty time stream
Long training sequence matrix.
Step 32, the long training matrix of high-throughput and orthogonal mapping matrix are generatedBe multiplied available HT-LTF
Matrix.
WhereinRepresent orthogonal mapping matrix n-thSTSRow n column element, nSTS=0,
1,…,NSTS, NSTSFor empty time stream quantity, n=0,1 ..., NHTLTF, NHTLTFIndicate high-throughput long training sequence in a frame
Number.
Step 33, cyclic shift is carried out with reference to the empty time stream treatment process of transmitting terminal.
Step 34, after matrix-vector cyclic shift with a fixed weighting matrixIt is multiplied, expands to NRXDimensional vector obtains
To signal xk:
WhereinRepresent N before matrixSTSColumn, NSTSRepresent empty time stream number
Amount；N=NSTS+NESS,NESSExtending space stream quantity is represented, k is subcarrier index value.
Step 35, in conjunction with the N locally extendedRXThe long training sequence in parallel vector that dimensional vector and step 2 obtain, passes through
yHTLTFk=HkQKxkMatrix inversion variation is done, channel matrix H is obtained.Wherein yHTLTFkHeight in the data after demodulating of channel receiving end is represented to gulp down
The amount of spitting long training sequence, QkRepresent weighting matrix, xkThe signal of step 34 generation is represented, k represents subcarrier index value.
Acquire channel matrix by matrixing, the frequency-region signal of receives link is passed sequentially through channel matrix by symbol based on
It calculates.
Step 4, it is mapped to the signal removal cyclic shift of empty time stream.
Step 5, the channel information at pilot tone moment is calculated by pilot frequency locationsPilot channel matrix can make signal optimal
Change, such as the pilot extraction of each symbol
Following steps specifically describe pilot channel estimation implementation process.
Step 51, with reference to consensus standard, the pilot value of first symbol of data in each empty time stream, such as local ginseng are extracted
Examine pilot extraction [x11 x12 x13 x14…]。
Step 52, each empty time stream pilot value is different, and pilot value exists according to first symbol pilot value in data
It is recycled in distinct symbols.By pilot value cycle characteristics in same empty time stream, the pilot value of symbol below is calculated.
Step 53, the pilot value of step 52 multiplied by the polarity sequence of pilot sub-carrierWherein k=1,2 ..., 126,
Step 54, by pilot correlation, dematrix equation is askedSuch asWhereinFor receiving end removal
Pilot signal after cyclic shift in data, XpilotFor local pilot signal.
A kind of channel based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system is claimed in the present invention
Estimation method is a kind of in order to solve the algorithm for estimating of channel errors minimum, while being connect to realize in wireless communication system
Receiving end accurately restores the transmission signal of transmitting terminal, realizes 802.11n signal receiving end and the corresponding inverse process of positive process
It is independent with separate, reduce the realization difficulty of signaling channel estimation method, propose one kind performance and terms of the computation complexity have compared with
Good compromise, with the low method of each correlation module independent design, implementation complexity.The present invention is the multiple antennas based on 802.11n
The method of ofdm system channel estimation provides unified, simple and efficient solution.
Claims (4)
1. a kind of channel estimation methods based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system, feature
It is, comprising the following steps:
A, after receiving end signal is demodulated, its high-throughput region is extracted, is frequency-region signal through N point FFT transform, then gone here and there
And it converts；
B, the signal after serial to parallel conversion is subjected to space reflection, is sequentially mapped to empty time stream；
C, it will be mapped to the signal removal cyclic shift delay of empty time stream；
D, step C treated signal carries out pilot channel estimation using the reception signal at local reference pilot value and pilot tone,
Calculate the channel response matrix at pilot tone moment
The step of space reflection are as follows:
B1, it extracts locally with reference to the corresponding empty time stream numbers matrix of high-throughput long training sequence generation:
Wherein NSTSFor empty time stream quantity, HH is empty time stream numbers matrix, HTLTF table
Show local with reference to high-throughput long training sequence；
B2, the long training matrix of high-throughput and orthogonal mapping matrix P are referred to by localHTLTFMultiplication obtains HT-LTF matrix；
HHT-LTFFor the long training matrix after orthogonal mapping, wherein PHTLTFIndicate orthogonal mapping matrix,It represents orthogonal
Mapping matrix n-thSTSRow n column element, nSTS=0,1 ..., NSTS, NSTSFor empty time stream quantity, n=0,1 ..., NHTLTF, NHTLTFTable
Show high-throughput long training sequence number in a frame；
B3, HT-LTF matrix is subjected to cyclic shift；
B4, the matrix of step B3 cyclic shift is multiplied with a fixed weighting matrix Q, expands to NTXDimensional vector:
B5, extension NTXDimensional vector, which does corresponding matrix inversion to the long training sequence of the obtained parallel vector of step A, to be changed, and channel is obtained
Matrix H.
2. a kind of letter based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system according to claim 1
Channel estimation method, it is characterised in that: cyclic shift refers to the empty time stream of 802.11n multiple antennas ofdm system transmitting terminal in the B3
Processing.
3. a kind of letter based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system according to claim 1
Channel estimation method, it is characterised in that: the fixed weighting matrix Q isWherein N
=NSTS+NESS,NESSRepresent extending space stream quantity, NSTSEmpty time stream quantity is represented,
4. a kind of letter based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system according to claim 1
Channel estimation method, it is characterised in that: the pilot channel estimation includes:
D1, the pilot value for extracting each empty time stream；
D2, the pilot value that each symbol is calculated according to the symbolic number complementation in each empty time stream；
D3, pilot value described in step D2 multiplied by the polarity sequence of pilot sub-carrier
D4, pilot correlation, dematrix equation are based onFind out channel response matrix
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611074345.7A CN106534030B (en) | 2016-11-29 | 2016-11-29 | A kind of channel estimation methods based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611074345.7A CN106534030B (en) | 2016-11-29 | 2016-11-29 | A kind of channel estimation methods based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106534030A CN106534030A (en) | 2017-03-22 |
| CN106534030B true CN106534030B (en) | 2019-05-31 |
Family
ID=58355129
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201611074345.7A Active CN106534030B (en) | 2016-11-29 | 2016-11-29 | A kind of channel estimation methods based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106534030B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR102075771B1 (en) * | 2017-07-12 | 2020-02-10 | 엘지전자 주식회사 | Method for transmitting / receiving signal in WLAN system and apparatus therefor |
| CN110113276B (en) * | 2018-02-01 | 2021-12-07 | 珠海全志科技股份有限公司 | OFDM frequency offset estimation method, system and device based on IEEE802.11 |
| CN110224963B (en) * | 2019-04-30 | 2020-03-24 | 高拓讯达（北京）科技有限公司 | Method and device for determining symbol timing synchronization position and storage medium |
| CN114257275A (en) * | 2020-09-22 | 2022-03-29 | 华为技术有限公司 | Method for determining cyclic shift delay value CSD and communication device |
| CN115001909B (en) * | 2022-05-05 | 2023-10-17 | 上海交通大学 | MIMO wireless communication rapid channel estimation device and method based on optical matrix calculation |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101035106A (en) * | 2007-04-02 | 2007-09-12 | 重庆邮电大学 | Method for using the pilot symbol and asymmetric pilot frequency to carry out the combined channel estimation |
| CN101399589A (en) * | 2007-09-30 | 2009-04-01 | 中兴通讯股份有限公司 | Multi-antenna pilot mapping method |
| WO2016029609A1 (en) * | 2014-08-27 | 2016-03-03 | 江苏中兴微通信息科技有限公司 | Methods and devices for transmission/reception of data for hybrid carrier modulation mimo system |
-
2016
- 2016-11-29 CN CN201611074345.7A patent/CN106534030B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101035106A (en) * | 2007-04-02 | 2007-09-12 | 重庆邮电大学 | Method for using the pilot symbol and asymmetric pilot frequency to carry out the combined channel estimation |
| CN101399589A (en) * | 2007-09-30 | 2009-04-01 | 中兴通讯股份有限公司 | Multi-antenna pilot mapping method |
| WO2016029609A1 (en) * | 2014-08-27 | 2016-03-03 | 江苏中兴微通信息科技有限公司 | Methods and devices for transmission/reception of data for hybrid carrier modulation mimo system |
Non-Patent Citations (1)
| Title |
|---|
| 基于自适应步长的MIMO-OFDM信道估计技术;田玮，等;《重庆邮电大学学报（自然科学版）》;20131031;第579-582页 |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106534030A (en) | 2017-03-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106534030B (en) | A kind of channel estimation methods based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system | |
| CN101692665B (en) | Demodulation method and demodulator of orthogonal frequency division multiplexing-multiple-input-multiple-output (OFDM-MIMO) system | |
| CN102739573B (en) | Channel estimation methods and channel estimator | |
| WO2009099013A1 (en) | Mobile communication system, reception device, and method | |
| US20030072254A1 (en) | Scattered pilot pattern and channel estimation method for MIMO-OFDM systems | |
| US20170257250A1 (en) | Methods and devices for transmission/reception of data for hybrid carrier modulation mimo system | |
| CN105915473B (en) | A kind of estimation of ofdm system parametric channel and equalization methods based on compressed sensing technology | |
| CN101917359B (en) | For receiving reception equipment and the method for signal in a wireless communication system | |
| JP2013081225A (en) | Systems and methods for enhanced channel estimation in wireless communication systems | |
| CN101005475A (en) | Method and system for synchronizing time and frequency in orthogonal frequency division multiplex communication | |
| CN101588335B (en) | Multiple input multiple output (MIMO) detecting method and MIMO detecting system utilizing correlation of signal channels | |
| EP2399372B1 (en) | OFDM receiver having a plurality of FFTS according to G-Rake structure | |
| CN109600327B (en) | Channel estimation method based on imaginary part interference utilization | |
| CN102143101A (en) | Mirror-extended frequency domain windowing orthogonal frequency division multiple access channel estimation method | |
| CN109347526B (en) | IM-OFDM signal processing method for Internet of vehicles | |
| CN104301275A (en) | Pilot frequency position determination method based on pilot frequency interval optimization and transmitter-receiver device | |
| US7557752B2 (en) | Apparatus and method for communication | |
| WO2012093333A1 (en) | Method of channel estimation, method of selecting pilot information, user equipment, and base station | |
| CN106341362B (en) | Pilot frequency sending method, pilot frequency receiving method and device thereof | |
| CN102870347B (en) | Channel quality estimation for MLSE receptor | |
| CN102130864A (en) | Channel estimation method and device | |
| CN101808064A (en) | Wireless receiving system and method and device for channel estimation | |
| CN102685060B (en) | Multi-user multiple input multiple output (MIMO) receiving method and device for orthogonal frequency division multiplexing system | |
| WO2012045244A1 (en) | Method and device for low complexity and high performance channel estimation | |
| CN103139108B (en) | A kind of three-dimensional MMSE channel estimation methods |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |