CN104702543B - Method for precoding and device - Google Patents
Method for precoding and device Download PDFInfo
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Abstract
An embodiment of the present invention provides a kind of method for precoding, the pilot signal sent by receiving transmitting terminal；Channel state information estimation is carried out according to the pilot signal, to obtain channel average and channel covariancc；According to the channel average and channel covariancc, pre-coding matrix is calculated；Transmitting terminal carries out the data-signal that needs are sent precoding according to the pre-coding matrix, and the receiving terminal separation pre-coding matrix carries out solution precoding to the precoded signal of reception.It can realize that the MIMO OFDM precodings based on average Signal to Interference plus Noise Ratio criterion can obtain better MIMO precodings unfailing performance and mimo system capacity under the conditions of statistical channel status information, be obtained under low relevant environment better than unfailing performance and mimo system capacity based on codebook precoding.
Description
Technical field
The present invention relates to moving communicating fields, and in particular to a kind of method for precoding and device.
Background technology
Multiple-input and multiple-output（MIMO）Technology can improve system space throughput under conditions of system bandwidth is not increased,
It can also be by means of significantly improving signal transmission quality to efficiently using for space diversity.In mimo systems, precoding technique
It is to be carried out in advance using channel state information (channel statement information, CSI) to sending signal in transmitting terminal
Processing eliminates intersymbol interference (ISI) or inter-user interference to reach, and improves the signal processing technology for the purpose of power system capacity.Often
The precoding type seen mainly includes linear predictive coding and nonlinear precoding.Linear predictive coding mainly has based on code book and non-code
This two kinds of linear predictive codings.Precoding based on code book is exactly that a known codebook set is shared in sending and receiving end, and code book is concentrated
Comprising multiple pre-coding matrixes, receiving terminal concentrates selection energy with a certain performance indicator according to the channel matrix of channel estimation in code book
Make the pre-coding matrix that system performance is optimal, then its code book sequence number is fed back into transmitting terminal, transmitting terminal is selected according to associated sequence numbers
Pre-coding matrix carries out precoding processing.Included using the problems of precoding based on code book, the design of code book should
It is match channels characteristic, and in practical applications, system may be operated in different fading environments, and day wire spacing is not yet
Identical to the greatest extent, antenna pattern and polarization are also not quite similar, this causes the design of code book that may become extremely complex；In addition, code book
Design usually also need to meet constant modulus property, limited character and Nested property etc..These factors largely influence and
Restrict the different requirements that the precoding technique scheme based on code book more neatly meets real system.With based on code book
MIMO precodings are compared, and non-code book MIMO precodings can be according to the dynamic change of channel condition, neatly selection and the characteristic of channel
The pre-coding matrix to match, MIMO precoding requirements under changing environment when can preferably meet complexity.
Existing MIMO precodings are difficult under middle Low SNR while take into account precoding reliability and system institute is real
This two big performance indicator of existing mimo system capacity.
The content of the invention
The object of the present invention is to provide a kind of method for precoding, to realize the precoding side based on average Signal to Interference plus Noise Ratio criterion
Method, so as to be obtained under low relevant environment better than unfailing performance and mimo system capacity based on codebook precoding.
To achieve the above object, on the one hand the embodiment of the present invention provides a kind of method for precoding, the described method includes：
Receive the uplink/downlink pilot signal that transmitting terminal is sent；
Channel state information estimation is carried out according to the uplink/downlink pilot signal, is assisted with obtaining channel average and channel
Variance；
According to the channel average and channel covariancc, pre-coding matrix is calculated；
When row channel is unsatisfactory for symmetry over/under, by the precoding matrix feedback to the transmitting terminal, in order to institute
It states transmitting terminal and precoding is carried out for the data-signal that needs are sent according to the pre-coding matrix；
According to the pre-coding matrix, solution precoding is carried out to the data-signal received.
Based in a first aspect, in the first possible embodiment, the pilot signal according to uplink/downlink carries out
Channel state information is estimated, to obtain channel average and channel covariancc, further comprises：
The channel status that pilot frequency symbol position is carried out to the pilot signal received is estimated, to obtain in the correlated time of channel
The interior LS channel estimation result based on frequency pilot sign；
The LS channel estimation based on frequency pilot sign within the correlated time of channel is obtained as a result, performing linear to described
Interpolation, with obtain data to be estimated channel estimation results on sub-carriers；
According to the LS channel estimation based on frequency pilot sign in the correlation time as a result, calculating the frequency pilot sign
Noise Variance Estimation value on sub-carriers；
Statistical channel status information in correlation time, the statistical channel shape are obtained according to the Noise Variance Estimation value
State information includes the channel average and the channel covariancc.
Based on the first possible embodiment, in second of possible embodiment, the described pair of pilot tone received
Signal carries out the channel status estimation of pilot frequency symbol position, to obtain the minimum two based on frequency pilot sign within the correlated time of channel
Multiply channel estimation results, specifically include：
By the N in a subframepA frequency pilot sign Yk,p(im)=Xk,p(im)Hk,p(im)+Wk,p(im),0≤m≤Np-1
It is integrated into：Yk,p=Xk,pHk,p+Wk,p
Wherein, k represents k-th of subcarrier；imIt is the location index in the OFDM symbol there are pilot signal, NpIt is one
Frequency pilot sign number on subcarrier；For the frequency pilot sign received,The pilot tone sent for transmitting terminal；NrFor reception antenna number, NtFor transmission antenna number；It is corresponding Frequency domain noise；Hk,p(im) represent the MIMO on k-th of subcarrier
Channel frequency domain response, and have
In the Yk,p=Xk,pHk,p+Wk,pIn,
According to the Yk,p=Xk,pHk,p+Wk,p, obtain the frequency domain response estimated on k-th of subcarrier of mimo channelWherein,For Xk,pPseudoinverse；
According to describedObtain the reception pilot matrix after the cascade in coherence time：
Wherein, Hk,p(im)≈Hk,p(i0), m=1 ..., Nc, Nc>NpFor the correlated time of channel corresponding OFDM symbol of equal value
Number, wherein：
According to the reception pilot matrix after the cascade in the coherence time：
Obtaining the LS channel estimation results based on frequency pilot sign within the correlated time of channel is：
Wherein,ForPseudoinverse.
It is described that the acquisition is being believed in the third possible embodiment based on second of possible embodiment
LS channel estimation based on frequency pilot sign in road correlation time is as a result, perform linear interpolation, with estimated data symbol institute
Channel estimation results in position, further comprise：
The concretely comprising the following steps to the channel estimation of the data symbol position to be estimated in time domain：
Hk,data(l ')=α1×Hk,p,LS(l)+β1×Hk,p,LS(l+Δl)
The wherein when Domain Index of l ' expressions Data Position to be estimated, and have l ＜ l ' ＜ l+ Δs l, l represent pilot signal when
Position in domain, Δ l represent the time domain interval of two adjacent pilot signals of time domain, and k represents subcarrier where pilot signal
Sequence number, interpolation coefficient α1, β1It calculates by the following method
And
The step of in frequency domain to the channel state information on the Data Position frequency domain index to be estimated, it is specially：
Hk′(l)=α2×Hk,S(l)+β2×Hk+Δk,S(l),S∈[p,data]；
The wherein frequency domain index of k ' expressions Data Position to be estimated, and there is k ＜ k ' ＜ k+ Δs k, k to represent pilot signal in frequency
Position in domain, Δ k represent the frequency interval of two adjacent pilot signals of frequency domain, interpolation coefficient α2, β2It counts by the following method
It calculates
Based on the third possible embodiment, in the 4th kind of possible embodiment, it is described according to it is described related when
In the LS channel estimation based on frequency pilot sign as a result, calculate the frequency pilot sign noise variance on sub-carriers
Estimate, specially：
Wherein | | Hk,p,LS(im+1)-Hk,p,LS(im)||FRepresent Frobenius norms, im+1,imRepresent same pilot tone OFDM
Adjacent pilot frequencies subcarrier sequence number on symbol, final Noise Variance Estimation value can be expressed from the next：
Wherein M is the occupied total number of sub-carriers of frequency pilot sign.
It is described according to the noise side in the 5th kind of possible embodiment based on the 4th kind of possible embodiment
Poor estimate obtains the statistical channel status information in correlation time, and the statistical channel status information includes the channel average
With the channel covariancc, specifically include：
According to the correlation time of communication channel, time domain sliding window length L is selected, wherein the sliding window length is corresponded in sliding window
The number of pilot symbols that subframe includes, according to the correlation bandwidth of channel, in the M that frequency domain is included from each coherence bandwidth0A pilot tone
The channel estimation results of subcarrier calculate moment i'sThe average of a channel state information：
And covariance：
WhereinVec () is represented matrix vector, ()HRepresent conjugate transposition.
It is described equal according to the channel in the 6th kind of possible embodiment based on the 5th kind of possible embodiment
Value and channel covariancc calculate pre-coding matrix, further comprise：
The system channel average obtained according to estimationChannel covarianccAnd noise varianceThe influence of noise is added in into channel averageWith channel covariancc ΦH,
Obtain new channel averageAnd channel covariancc
Wherein：
Wherein noise covariance matrix
According toAnd ΦH,n, calculating matrixWherein
Wherein X[i,j]I-th j dimension for representing X is Nr×NrSub- square；
By matrix Z(s)Cholesky decomposition is carried out, obtains matrix L(s)：
Z(s)=L(s)·(L(s))H；
To L(s)Matrix carries out singular value decomposition：
Obtain Z(s)Eigenvalues Decomposition expression formula
Pre-coding matrix based on average Signal to Interference plus Noise Ratio criterion calculates by the following method
Wherein
WhereinIt is matrix
R nonzero eigenvalue, μ be the water filling factor.P is that transmitting terminal carries all subcarriers of user data and transmitting antenna sends work(
The summation of rate.
It is described to be received using receiving terminal after precoding based in a first aspect, in the 7th kind of possible embodiment
Signal is：
Yk(l)=Hk(l)·B·Xk(l)+Wk(l)
Wherein
Estimate to obtain the channel state information H of non-pilot character position by time domain and frequency domain two-dimensional linear interpolationk(l),
With reference to the pre-coding matrix B, equivalent channel matrix H is determinedE,k(l), i.e.,
HE,k(l)=Β Hk(l)
According to equivalent combined channel matrix HE,k(l) using least mean-square error as criterion, receiving terminal can carry out solution and prelist
Code and the joint-detection of MIMO detections receive
Second aspect, an embodiment of the present invention provides a kind of pre-coding apparatus, described device includes：
Receiving unit, for receiving the pilot signal of transmitting terminal transmission；
Estimation unit, for according to uplink and downlink pilot signal carry out channel state information estimation, with obtain channel average and
Channel covariancc；
Computing unit, for according to the channel average and channel covariancc, calculating pre-coding matrix；
Feedback unit, for giving the precoding matrix feedback to the hair when uplink and downlink channel is unsatisfactory for symmetry
Sending end, in order to which the transmitting terminal carries out precoding according to the pre-coding matrix for the data-signal that needs are sent.
Decoding unit, for according to the pre-coding matrix, solution precoding to be carried out to the data-signal received.
Based on second aspect, in the first possible embodiment, the estimation unit is specifically used for：
The channel status that pilot frequency symbol position is carried out to the pilot signal received is estimated, to obtain in the correlated time of channel
The interior LS channel estimation result based on frequency pilot sign；
The LS channel estimation based on frequency pilot sign within the correlated time of channel is obtained as a result, performing linear to described
Interpolation, with obtain data to be estimated channel estimation results on sub-carriers；
According to the LS channel estimation based on frequency pilot sign in the correlation time as a result, calculating the frequency pilot sign
Noise Variance Estimation value on sub-carriers；
Statistical channel status information in correlation time, the statistical channel shape are obtained according to the Noise Variance Estimation value
State information includes the channel average and the channel covariancc.
By method for precoding provided in an embodiment of the present invention, the pilot signal sent by receiving transmitting terminal；According to institute
It states pilot signal and carries out channel state information estimation, to obtain channel average and channel covariancc；According to the channel average and
Channel covariancc calculates pre-coding matrix；By the precoding matrix feedback to the transmitting terminal, in order to the transmitting terminal root
According to the pre-coding matrix precoding is carried out for the data-signal that needs are sent.It can realize in statistical channel status information condition
Under the MIMO-OFDM precodings based on average Signal to Interference plus Noise Ratio criterion can preferably handle MIMO precodings unfailing performance and MIMO systems
System capacity, obtains under low relevant environment better than unfailing performance and mimo system capacity based on codebook precoding.
Description of the drawings
It to describe the technical solutions in the embodiments of the present invention more clearly, below will be to embodiment or description of the prior art
Needed in attached drawing be briefly described, it should be apparent that, the accompanying drawings in the following description be only the present invention some
Embodiment, for those of ordinary skill in the art, without having to pay creative labor, can also be according to these
Attached drawing obtains other attached drawings.
Fig. 1 is that the MIMO precoding techniques based on average Signal to Interference plus Noise Ratio criterion implement signal under the conditions of TD-LTE system
Figure.
Fig. 2 is receiving terminal under the conditions of TD-LTE system, and the MIMO precodings reception processing based on average Signal to Interference plus Noise Ratio criterion is shown
Meaning block diagram.
Fig. 3 is the flow chart that the embodiment of the present invention provides method for precoding；
Fig. 4 is transmitting terminal under the conditions of TD-LTE system, and the MIMO precodings transmission processing based on average Signal to Interference plus Noise Ratio criterion is shown
Meaning block diagram；
Fig. 5 is that the unfailing performance of the MIMO precodings based on average Signal to Interference plus Noise Ratio criterion under high correlation ETU1 channel conditions is shown
It is intended to；
Fig. 6 is the MIMO pre-coding systems capacity signal based on average Signal to Interference plus Noise Ratio criterion under high correlation ETU1 channel conditions
Figure；
Fig. 7 is that the unfailing performance of the MIMO precodings based on average Signal to Interference plus Noise Ratio criterion under low correlation ETU1 channel conditions is shown
It is intended to；
Fig. 8 is the MIMO pre-coding systems capacity signal based on average Signal to Interference plus Noise Ratio criterion under low correlation ETU1 channel conditions
Figure；
Fig. 9 is the MIMO precodings unfailing performance signal based on average Signal to Interference plus Noise Ratio criterion under high correlation EVA1 channel conditions
Figure；
Figure 10 is that the MIMO pre-coding system capacity based on average Signal to Interference plus Noise Ratio criterion shows under high correlation EVA1 channel conditions
It is intended to；
Figure 11 is that the MIMO precoding unfailing performances based on average Signal to Interference plus Noise Ratio criterion are shown under low correlation EVA1 channel conditions
It is intended to；
Figure 12 is that the MIMO pre-coding system capacity based on average Signal to Interference plus Noise Ratio criterion shows under low correlation EVA1 channel conditions
It is intended to；
Figure 13 is the MIMO precodings unfailing performance signal based on average Signal to Interference plus Noise Ratio criterion under high correlation EPA channel conditions
Figure；
Figure 14 is the MIMO pre-coding systems capacity signal based on average Signal to Interference plus Noise Ratio criterion under high correlation EPA channel conditions
Figure；
Figure 15 is the MIMO precodings unfailing performance signal based on average Signal to Interference plus Noise Ratio criterion under low correlation EPA channel conditions
Figure；
Figure 16 is the MIMO pre-coding systems capacity signal based on average Signal to Interference plus Noise Ratio criterion under low correlation EPA channel conditions
Figure；
Figure 17 is the structure diagram of pre-coding apparatus provided in an embodiment of the present invention；
Figure 18 is another structure diagram of pre-coding apparatus provided in an embodiment of the present invention.
Specific embodiment
Below by drawings and examples, technical scheme is described in further detail.
Technical solution provided in an embodiment of the present invention can be applied to various cordless communication networks, such as：The whole world is mobile logical
Letter（Global system for mobile communication, referred to as GSM）System, CDMA（code
Division multiple access, referred to as CDMA）System, wideband code division multiple access（wideband code division
Multiple access, referred to as WCDMA）System, universal mobile communications（universal mobile
Telecommunication system, referred to as UMTS）System, General Packet Radio Service（general packet
Radio service, referred to as GPRS）System, Long Term Evolution（Long term evolution, referred to as LTE）System, elder generation
Into Long Term Evolution（Long term evolution advanced, referred to as LTE-A）System, global interconnection inserting of microwave
（Worldwide interoperability for microwave access, referred to as WiMAX）System etc..Term " net
Network " and " system " can be replaced mutually.
In embodiments of the present invention, base station（Base station, referred to as BS）Can be and user equipment（user
Equipment, referred to as UE）Or other communication sites such as relay, the equipment to communicate, base station can provide specific object
Manage the communication overlay in region.For example, base station can be specifically the base transceiver station in GSM or CDMA（base transceiver
Station, referred to as BTS）Or base station controller（Base station controller, referred to as BSC）；Can also be
Node B in UMTS（Node B, referred to as NB）Or the radio network controller in UMTS（radio network
Controller, referred to as RNC）；It can also be the evolved base station in LTE（Evolutional node B, referred to as ENB
Or eNodeB）；Or or cordless communication network in offer access service other access network equipments, the present invention simultaneously
It does not limit.
In embodiments of the present invention, UE can be distributed in entire wireless network, and each UE can be static or mobile
's.UE is properly termed as terminal（terminal）, mobile station（mobile station）, subscriber unit（subscriber unit）,
Platform（station）Deng.UE can be cellular phone（cellular phone）, personal digital assistant（personal
Digital assistant, referred to as PDA）, radio modem（modem）, wireless telecom equipment, handheld device
（handheld）, laptop computer（laptop computer）, wireless phone（cordless phone）, wireless local loop
（Wireless local loop, referred to as WLL）Platform etc..
Fig. 1 shows that implement the MIMO proposed by the invention based on average Signal to Interference plus Noise Ratio criterion in TD-LTE system pre-
The embodiment schematic diagram of coding.In order to implement the MIMO precodings based on average Signal to Interference plus Noise Ratio criterion, transmitting terminal source signal
After scrambled and modulation treatment, transmitting terminal precoding module is sent, definite prelist is calculated according to pre-coding matrix computing module
Code matrix performs transfer pre-coding processing to sending data, then resource particle is sent to map, using ofdm signal generation module
OFDM symbol is generated afterwards send transmission antenna port through MIMO-OFDM transmissions.In order to implement based on average Signal to Interference plus Noise Ratio criterion
MIMO precodings, TD-LTE system receiving terminal receives signal via reception antenna port, through past CP, after OFDM demodulation, from
Time-domain signal switches back to frequency-region signal, then solves resource particle mapping, then performs MIMO by solving precoding module and prelists
The joint-detection of code restores the source signal of base station end transmission after last demodulated and descrambling.In embodiments of the present invention,
Base station and user equipment may be performed as the main body of method provided by the invention, for example, when base station is as receiving terminal, base station
The pilot signal of user equipment transmission is received by up channel, and obtains channel average and channel covariancc, and calculates and prelists
Code matrix.On the contrary, if base station, as transmitting terminal, user equipment is then receiving terminal, and user equipment receives base by down channel
It stands the pilot signal sent, and calculates pre-coding matrix.
Fig. 2 shows that MIMO precoding of the receiving terminal based on average Signal to Interference plus Noise Ratio criterion receives under the conditions of TD-LTE system
Handle schematic block diagram.Receiving terminal receives signal via reception antenna port, removes cyclic prefix CP, after OFDM demodulation, from time domain
Signal switches back to frequency-region signal；It is then passed through solution resource particle mapping；Channel estimation module is estimated according to the pilot signal of reception
Go out the channel gain of pilot frequency symbol position, and count channel average and channel covariancc, then precoding computing module according to
Channel average and channel covariancc, which calculate, determines pre-coding matrix, channel reciprocity cannot be utilized to estimate channel status in transmitting terminal
During information, precoding matrix feedback will be implemented precoding processing by receiving terminal by feedback channel to transmitting terminal.Precoding
Matrix and the channel for implementing the data symbol positions that two-dimensional linear interpolation is calculated according to pilot frequency symbol position channel estimation
Estimation will send solution precoding and MIMO joint-detection modules.Precoding is solved with MIMO joint detection results by the mapping of solution layer, solution
It adjusts, after descrambling, restores transmitting terminal and send message.
Based on above system, an embodiment of the present invention provides a kind of method for precoding, in the present embodiment, transmitting terminal can be with
It is mobile phone or base station, corresponding, receiving terminal can be base station or mobile phone, and when transmitting terminal is mobile phone, receiving terminal is base station,
When transmitting terminal is base station, receiving terminal is mobile phone, as shown in figure 3, the method includes：
301, receiving terminal receives the uplink/downlink pilot signal that transmitting terminal is sent；
302, receiving terminal carries out channel state information estimation according to the uplink/downlink pilot signal, equal to obtain channel
Value and channel covariancc；
More specifically, which further comprises：Receiving terminal carries out pilot frequency symbol position to the pilot signal received
Channel status is estimated, to obtain the LS channel estimation result based on frequency pilot sign within the correlated time of channel；
The LS channel estimation based on frequency pilot sign within the correlated time of channel is obtained as a result, performing linear to described
Interpolation, with obtain data to be estimated the pilot signal channel estimation results on sub-carriers；
According to the LS channel estimation based on frequency pilot sign in the correlation time as a result, calculating the frequency pilot sign
Noise Variance Estimation value on sub-carriers；
Statistical channel status information in correlation time, the statistical channel shape are obtained according to the Noise Variance Estimation value
State information includes the channel average and the channel covariancc.
303, receiving terminal calculates pre-coding matrix according to the channel average and channel covariancc；
304, when row channel is unsatisfactory for symmetry over/under, receiving terminal gives the precoding matrix feedback to the transmission
End, in order to which the transmitting terminal carries out precoding according to the pre-coding matrix for the data-signal that needs are sent；
305, receiving terminal carries out solution precoding according to the pre-coding matrix to the data-signal received.
Specifically, the channel status of the pilot signal progress pilot frequency symbol position to receiving is estimated, to obtain
The LS channel estimation based on frequency pilot sign within the correlated time of channel is taken as a result, can be realized by such a way：
TD-LTE system receiving terminal is received via reception antenna port, is received after removal cyclic prefix CP, OFDM demodulation
To frequency domain pilot signal be
Yk,p(im)=Xk,p(im)Hk,p(im)+Wk,p(im),0≤m≤Np-1 (1)
Wherein imIt is the location index in the OFDM symbol there are pilot signal, NpIt is the frequency pilot sign on a subcarrier
Number；For the frequency pilot sign received, NrFor reception antenna number, k is represented
K-th of subcarrier；For the pilot matrix that transmitting terminal is sent, NtFor transmission antenna
Number；It is corresponding Frequency domain noise；Hk,p(im) represent the MIMO on DFT frequencies k
Channel frequency response, and have
By the N in a subframepA frequency pilot sign combines
Yk,p=Xk,pHk,p+Wk,p (3)
Wherein
On the basis of (3) formula measuring signal, the LS channel estimation results that can obtain frequency pilot sign are：
WhereinFor Xk,pPseudoinverse.Consider that channel gain does not substantially become in channel coherency time in real system
Change, i.e. Hk,p(im)≈Hk,p(i0), m=1 ..., Nc, wherein Nc>NpFor the correlated time of channel corresponding OFDM symbol number of equal value, then
(3) formula can be rewritten as following cascade observation signal sequence：
Wherein
On the basis of (5) formula measuring signal, the LS channels based on frequency pilot sign within the correlated time of channel can be obtained
Estimated result is：
WhereinForPseudoinverse.
On the basis of pilot frequency symbol position channel state information is estimated, it is by time domain and frequency domain two-dimensional linear interpolation
It can be derived from the channel state information of non-pilot character position；Namely the acquisition was based on leading within the correlated time of channel
The LS channel estimation of frequency symbol is as a result, perform linear interpolation, to obtain data to be estimated where the pilot signal
Channel estimation results on subcarrier；
First, in time domain to it is described when former residence Data Position when Domain Index on channel state information the step of, tool
Body is：
Hk,data(l ')=α1×Hk,p,LS(l)+β1×Hk,p,LS(l+Δl) (7)
Wherein l ' expressions Data Position to be estimated when Domain Index and have l ＜ l ' ＜ l+ Δs l, l represent pilot signal when
Position in domain, Δ l represent the time domain interval of two adjacent reference signals of time domain, and k represents subcarrier where pilot signal
Sequence number, interpolation coefficient α1, β1It calculates by the following method
Subcarrier where frequency pilot sign can be obtained after temporal interpolation is estimated in the channel of time domain non-pilot character position
Count result.
Afterwards, in frequency domain to it is described when former residence Data Position when Domain Index on channel state information the step of, tool
Body is：
Hk′(l)=α2×Hk,S(l)+β2×Hk+Δk,S(l),S∈[p,data] (9)
Wherein the frequency domain of k ' expressions Data Position to be estimated indexes and has k ＜ k ' ＜ k+ Δs k, k to represent pilot signal in frequency
Position in domain, Δ k represent the frequency interval of two adjacent reference signals of frequency domain, interpolation coefficient α2, β2It counts by the following method
It calculates
It can estimate to obtain the channel estimation results of all data symbol positions after Frequency domain interpolation.
From (6) formula
Afterwards, according to the LS channel estimation based on frequency pilot sign in the correlation time as a result, being led described in calculating
Frequency symbol Noise Variance Estimation value on sub-carriers；
Realized especially by following manner, due to adjacent pilot frequencies subcarrier upper signal channel in same OFDM symbol gain very
It is close, i.e. Hk,p(im)≈Hk,p(im+ 1) this feature, can be utilized to go out frequency pilot sign place using following methods direct derivation
Noise Variance Estimation on carrier wave k
Wherein | | Hk,p,LS(im+1)-Hk,p,LS(im)||FRepresent Frobenius norms.Final total Noise Variance Estimation value
It can be expressed from the next：
Wherein M represents the occupied total number of sub-carriers of frequency pilot sign.
Finally, according to the correlation time of communication channel, time domain sliding window length L is reasonably selected（Correspond to subframe bag in sliding window
The number of pilot symbols included）, according to the correlation bandwidth of channel, in the M that frequency domain is included from each coherence bandwidth0A pilot sub-carrier
Channel estimation results estimate to calculate moment i's by the following methodThe average of a channel state information
And covarianceWherein N is the total number of sub-carriers for carrying user data.
Wherein,Vec () represents the vector quantization of matrix, ()HRepresent conjugate transposition.
Calculating the average of channel state information aboveAnd covarianceWhen, according in coherence in frequency domain bandwidth
Adjacent M0Sub-carrier channels estimated result statistics calculates channel state information in coherence in frequency domain bandwidth where a frequency pilot sign
AverageAnd covarianceSince the different sub-carrier characteristic of channel is approximately the same in coherence bandwidth, it is believed that
The average of the corresponding channel state information of each subcarrier is in correlation bandwidthCovariance is
It examines in MIMO pre-coding systems, B represents pre-coding matrix, and H represents Nr×NtMimo channel, wherein NrTo connect
Receive antenna number, NtFor transmitting antenna number, A, which is represented, receives detection matrix, then corresponding error vectorCovariance matrix
For
Wherein
Ry=E { yyH}=HBBHHH+Rn (18)
If the covariance matrix of white complex gaussian noiseReceiving terminal is detected using linear minimum mean-squared error LMMSE
Matrix, i.e.,
Covariance matrix can be further written as：
The then Signal to Interference plus Noise Ratio SINR of corresponding i-th of transmission symboliMSE corresponding with itsiThere is following relation：
Wherein
Wherein biThe i-th column vector of representing matrix B, [X]i,jThe i row j column elements of representing matrix X.Then all transmission symbols
The sum of Signal to Interference plus Noise Ratio can represent as follows：
Under total transmit power constraints, the letters that optimization aim can be arranged to to maximize all transmission symbols dry are made an uproar
Than the sum of to determine pre-coding matrix B, i.e., corresponding precoding optimization design problem can be described as following optimization problem
Wherein P/N represents that transmitting terminal distributes to total transmit power of each subcarrier, and Tr () represents mark.According to the friendship of mark
Transsexual matter Tr (AB)=Tr (BA), object function can be with equivalent as follows：
EH{tr(BHHHHB) }=EH{tr(HBBHHH)=EH{tr(HQHH)} (25)
Wherein Q=BBHRepresent the autocorrelation matrix of transmission precoding.If the covariance matrix of white complex gaussian noiseThen the form of above-mentioned object function remains unchanged, and need to only replace as follows：
WhereinRepresent Kronecker products.
Solution for (24) formula optimization problem can calculate the definite optimal precoding square being averaged under Signal to Interference plus Noise Ratio criterion
Battle array B.DefinitionWherein unvec () is the inverse operator of vec (), and utilizes variableZero-mean and mark commutative properties, and based on the statistics DCSIT channel models in (16) formula, the object function in (24) formula can
To be further written as：
Wherein
Wherein ()TThe transposition of representing matrix, here with trace function property Tr (AHB)=(vec (A))HVec (B),
And combine channel covariancc ΦHDefinition.(28) formula is substituted into (27) formula, and the Operation Nature accumulated according to Kronecker, target
Function can be transformed to：
Wherein ()*The conjugation of representing matrix,(29) equation of mark is applied in formula
Property Tr (A)=Tr (AT)。NrNt×NrNtTie up matrix(i, j) a Nr×NrSubmatrix is proportional units battle array, i.e.,Wherein qijRepresent the i-th row j column elements of Q, δrsIt is Kronecker delta functions (δrs=
1, r=s;δrs=0, r ≠ s), basis in formulaThe special shape of matrix and the mark of matrix are equal to matrix diagonals line element
This definition of the sum of element.(29) formula can be further simplified as follows：
Wherein X[i,j]Represent (i, j) a N of Xr×NrSubmatrix.Therefore the object function in (24) formula can be rewritten as
Because the element of Z matrixes is the mark of positive semidefinite matrix sub-block, Z matrixes are also positive semi-definite.It can prove matrix Q's
Base is consistent with Z, i.e., ifRepresent the Eigenvalues Decomposition of Z, then the Eigenvalues Decomposition of Q is
Wherein, ΛQRepresent the eigenvalue matrix of Q.The Eigenvalues Decomposition of Z and above formula are substituted into object function, ΛQSolution
Problem has reformed into following optimization problem
Wherein λZi, λQiZ, the characteristic value of Q are represented respectively.Because Z matrixes are represented by channel average and channel covariancc.If
Consider subchannel mean allocation transmit power, i.e. ΛQDiagonal entry be equal toIf consider transmit powerPass through work(
Every transmission antenna is distributed in rate water filling, then ΛQIt calculates by the following method
Wherein,It is matrix
R nonzero eigenvalue, μ be the water filling factor.
Specifically, the MIMO-OFDM system channel averages obtained according to estimationChannel covarianccWith noise side
DifferenceThe influence of noise is added in channel average and channel covariancc, obtains new channel averageAnd channel covarianccWherein
Wherein, noise covariance matrixAccording toAnd ΦH,n, calculating matrix
Wherein：
Wherein X[i,j]I-th j dimension for representing X is Nr×NrSub- square.By matrix Z(s)Carry out Cholesky points
Solution, obtains matrix L(s)
Z(s)=L(s)·(L(s))H (38)
Then to L(s)Matrix carries out singular value decomposition
So as to obtain Z(s)Eigenvalues Decomposition expression formula
Pre-coding matrix then based on average Signal to Interference plus Noise Ratio criterion calculates by the following method
Wherein
If considering transmit power P being averagely allocated to every transmission antenna,It calculates by the following method
If consider transmit powerEvery transmission antenna is distributed to by power water filling, thenIt calculates by the following method
WhereinIt is matrix
R nonzero eigenvalue, μ be the water filling factor.
The form of pre-coding matrix B is observed,For power allocation matrix, power allocation case is reflected,It is matrix
Z(s)Unitary matrice, multiplexed signals decomposes several mutually orthogonal directions and transmitted by the mutually orthogonal characteristic of column vector, can be with
See multimode wave beam formed matrix as, and input forming matrix may be considered unit matrix I.And restrictive conditionThen
Meet general power permanent character.Obviously, using (41) formula shown in pre-coding matrix, the average Signal to Interference plus Noise Ratio of receiving terminal is
By Such analysis as it can be seen that when calculating definite each subcarrier pre-coding matrix according to statistics DCSIT information, prelist
Code scheme mainly depends on the channel average with each sub-carrier channelsChannel covarianccIn view of coherence in frequency domain bandwidth
The channel average of interior different sub-carrier channelChannel covarianccIt is essentially identical, determine different sub-carrier actually calculating
During the pre-coding matrix of channel, channel can accordingly can be divided by coherence in frequency domain bandwidthGroup calculates definite pair
The pre-coding matrix answered.
After receiving terminal, the data sent in the pre-coding matrix using feedback for receiving transmitting terminal transmission, using pre-
Receiving terminal reception signal is after coding：
Yk(l)=Hk(l)·B·Xk(l)+Wk(l) (46)
WhereinReceiving terminal is being estimated
Go out on the basis of pilot frequency symbol position channel state information, estimate to obtain non-pilot symbol by time domain and frequency domain two-dimensional linear interpolation
The channel state information H of number positionk(l), with reference to definite pre-coding matrix B is calculated, definite equivalent channel square can be calculated
Battle array HE,k(l), i.e.,
HE,k(l)=Β Hk(l) (47)
According to equivalent combined channel matrix HE,k(l) using least mean-square error as criterion, reception can carry out solution precoding
It is received with the joint-detection of MIMO detections
Fig. 4 shows and is sent out under the conditions of TD-LTE system in order to implement the MIMO precodings based on average Signal to Interference plus Noise Ratio criterion
Sending end end handles schematic block diagram.When uplink downlink meets reciprocity, transmitting terminal receives signal, SC- via antenna port
After FDMA demodulation, solution resource particle mapping is then passed through, channel estimation module is estimated according to the uplink pilot signal of reception and led
The channel gain of frequency symbol position, and channel average and channel covariancc are counted, then precoding computing module is according to channel
Average and channel covariancc, which calculate, determines downlink precoding matrix.Channel reciprocity cannot be utilized to estimate channel status in transmitting terminal
During information, transmitting terminal will be received by feedback channel and calculate definite pre-coding matrix so that transmitting terminal implements precoding by receiving terminal
Processing.
Fig. 5-Figure 16 compare SVD linear predictive codings (average power allocation SVD-ave and power water filling SVD-wf),
MIMO precodings (SINR mean) scheme based on average Signal to Interference plus Noise Ratio criterion under the conditions of DCSIT and based on maximizing SINR
The codebook precoding (average power allocation SINRave and power water filling SINRwf) of codebook selecting scheme is in ETU1, EVA1 and EPA
Bit error rate performance and power system capacity under channel condition, the feedback delay of wherein channel state information are the transmission of a subframe
Time, feedback granularity are a subframe, and the time domain feedback granularity of PMI is a subframe in closed loop code book feedback scheme, and frequency domain is anti-
Feedback granularity is 2 resource blocks, and the time domain feedback granularity of linear predictive coding SVD is an OFDM symbol, and frequency domain feedback granularity is 1
Resource block, simulated conditions are as shown in table 1.It can draw to draw a conclusion from Fig. 5-Figure 16：
In a first aspect, from the point of view of precoding unfailing performance and the system ergodic capacity realized using precoding, SVD-wf
Optimal compromise can be obtained between code performance and power system capacity prelisting, SVD-ave takes second place, Signal to Interference plus Noise Ratio average SINRave and
The code performance that prelists of SINRwf is substantially suitable with the codebook precoding based on SINR criterions.
Second aspect, under low associated channel condition, the precoding side based on Signal to Interference plus Noise Ratio average SINRave and SINRwf
Case can be obtained close to the unfailing performance and power system capacity of SVD pre-coding schemes and the codebook precoding phase based on SINR criterions
When.This shows that the pre-coding scheme based on Signal to Interference plus Noise Ratio average provides one for the precoding implementation under low associated channel condition
The feasible technical solution of kind.
The third aspect, in low signal-to-noise ratio region, SINRave precodings unfailing performance is better than SINRwf precodings, and system
Capacity is slightly inferior to SINRwf, and in high s/n ratio region, the code performance that prelists of two kinds of power allocation schemes is suitable.This shows power
Waterflood project is little to the performance gain based on average SINR criterions precoding, and mean allocation power implements simple, SINRave
Precoding is a kind of simple beneficial technical solution.
Consider the unfailing performance and power system capacity achieved by system, system is realized to channel state information in addition
It is a kind of precoding technique side rational under the conditions of DCSIT based on Signal to Interference plus Noise Ratio average criterion pre-coding scheme from the point of view of it is required that
Case.
Correspondingly, the embodiment of the present invention additionally provides a kind of pre-coding apparatus, described device can be that base station can also be
User equipment, when described device is base station, base station is receiving terminal, and transmitting terminal is user equipment, if on the contrary, described device is use
Family equipment, then base station is transmitting terminal, and receiving terminal is user equipment, and as seen from Figure 17, described device includes：
Receiving unit 701, for receiving the pilot signal of transmitting terminal transmission；
Estimation unit 702, it is equal to obtain channel for carrying out channel state information estimation according to uplink and downlink pilot signal
Value and channel covariancc；
Computing unit 703, for according to the channel average and channel covariancc, calculating pre-coding matrix；
Feedback unit 704, it is described for giving the precoding matrix feedback when uplink and downlink channel is unsatisfactory for symmetry
Transmitting terminal, in order to which the transmitting terminal carries out precoding according to the pre-coding matrix for the data-signal that needs are sent.
Decoding unit 705, for according to the pre-coding matrix, solution precoding to be carried out to the data-signal received.
Further, the estimation unit is specifically used for：
The channel status that pilot frequency symbol position is carried out to the pilot signal received is estimated, to obtain in the correlated time of channel
The interior LS channel estimation result based on frequency pilot sign；
The LS channel estimation based on frequency pilot sign within the correlated time of channel is obtained as a result, performing linear to described
Interpolation, with obtain data to be estimated channel estimation results on sub-carriers；
According to the LS channel estimation based on frequency pilot sign in the correlation time as a result, calculating the frequency pilot sign
Noise Variance Estimation value on sub-carriers；
Statistical channel status information in correlation time, the statistical channel shape are obtained according to the Noise Variance Estimation value
State information includes the channel average and the channel covariancc.
Close how pre-coding apparatus in this present embodiment calculates channel average and covariance and obtain pre-coding matrix
Method may be referred to foregoing embodiment, seldom repeat.
As shown in figure 18, the embodiment of the present invention additionally provides a kind of pre-coding apparatus, and described device can be that base station also may be used
To be user equipment, when described device is base station, base station is receiving terminal, and transmitting terminal is user equipment, if on the contrary, described device
For user equipment, then base station is transmitting terminal, and receiving terminal is user equipment, as seen from Figure 18, described device include transmitter 182,
Receiver 181, memory 183 and the processor 184 being connected respectively with transmitter 182, receiver 181 and memory 183.When
So, base station can also include the universal components such as antenna, baseband process component, middle radio frequency processing part, input/output unit, this hair
Bright embodiment no longer any restrictions herein.
Wherein, batch processing code is stored in memory 183, and processor 184 is used to call the journey stored in memory
Sequence code, for performing following operation：
The uplink/downlink pilot signal of transmitting terminal transmission is received by receiver；
Channel state information estimation is carried out according to the uplink/downlink pilot signal, is assisted with obtaining channel average and channel
Variance；
According to the channel average and channel covariancc, pre-coding matrix is calculated；
When row channel is unsatisfactory for symmetry over/under by transmitter, the precoding matrix feedback is given to the transmission
End, in order to which the transmitting terminal carries out precoding according to the pre-coding matrix for the data-signal that needs are sent；
According to the pre-coding matrix, solution precoding is carried out to the data-signal received.
It is carried it should be noted that the pre-coding apparatus shown in Figure 17 and Figure 18 can be used to implement above method embodiment
Any method supplied, details are not described herein.
Professional should further appreciate that, be described with reference to the embodiments described herein each exemplary
Unit and algorithm steps can be realized with the combination of electronic hardware, computer software or the two, hard in order to clearly demonstrate
The interchangeability of part and software generally describes each exemplary composition and step according to function in the above description.
These functions are performed actually with hardware or software mode, specific application and design constraint depending on technical solution.
Professional technician can realize described function to each specific application using distinct methods, but this realization
It is it is not considered that beyond the scope of this invention.
The step of method or algorithm for being described with reference to the embodiments described herein, can use hardware, processor to perform
The combination of software module or the two is implemented.Software module can be placed in random access memory（RAM）, memory, read-only memory
（ROM）, electrically programmable ROM, electrically erasable ROM, register, hard disk, moveable magnetic disc, CD-ROM or technical field
In any other form of storage medium well known to interior.
Above-described specific embodiment has carried out the purpose of the present invention, technical solution and advantageous effect further
It is described in detail, it should be understood that the foregoing is merely the specific embodiments of the present invention, is not intended to limit the present invention
Protection domain, within the spirit and principles of the invention, any modification, equivalent substitution, improvement and etc. done should all include
Within protection scope of the present invention.
Claims (10)
1. a kind of method for precoding, which is characterized in that the described method includes：
Receive the uplink/downlink pilot signal that transmitting terminal is sent；
Channel state information estimation is carried out according to the uplink/downlink pilot signal, to obtain channel average and channel covariancc；
According to the channel average and channel covariancc, pre-coding matrix is calculated；
When row channel is unsatisfactory for symmetry over/under, by the precoding matrix feedback to the transmitting terminal, in order to the hair
Sending end carries out precoding according to the pre-coding matrix for the data-signal that needs are sent；
According to the pre-coding matrix, solution precoding is carried out to the data-signal received.
2. method for precoding as described in claim 1, which is characterized in that the pilot signal according to uplink/downlink carries out
Channel state information is estimated, to obtain channel average and channel covariancc, further comprises：
The channel status that pilot frequency symbol position is carried out to the pilot signal received is estimated, to obtain the base within the correlated time of channel
In the LS channel estimation result of frequency pilot sign；
The LS channel estimation based on frequency pilot sign within the correlated time of channel is obtained as a result, performing in linear to described
Insert, with obtain data to be estimated channel estimation results on sub-carriers；
According to the LS channel estimation based on frequency pilot sign in the correlation time as a result, where calculating the frequency pilot sign
Noise Variance Estimation value on subcarrier；
Statistical channel status information in correlation time, the statistical channel state letter are obtained according to the Noise Variance Estimation value
Breath includes the channel average and the channel covariancc.
3. method for precoding as claimed in claim 2, which is characterized in that the described pair of pilot signal received carries out pilot tone symbol
The channel status estimation of number position, to obtain the LS channel estimation knot based on frequency pilot sign within the correlated time of channel
Fruit specifically includes：
By the N in a subframepA frequency pilot sign Yk,p(im)=Xk,p(im)Hk,p(im)+Wk,p(im),0≤m≤Np- 1 is integrated into：
Yk,p=Xk,pHk,p+Wk,p
Wherein, k represents k-th of subcarrier；imIt is the location index in the OFDM symbol there are pilot signal, NpIt is that a son carries
Frequency pilot sign number on ripple；For the frequency pilot sign received,The pilot tone sent for transmitting terminal；NrFor reception antenna number, NtFor transmission antenna number；It is corresponding Frequency domain noise；Hk,p(im) represent the MIMO on k-th of subcarrier
Channel frequency domain response, and have
In the Yk,p=Xk,pHk,p+Wk,pIn,
According to the Yk,p=Xk,pHk,p+Wk,p, obtain the frequency domain response estimated on k-th of subcarrier of mimo channelWherein,For Xk,pPseudoinverse；
According to describedObtain the reception pilot matrix after the cascade in coherence time：
Wherein, Hk,p(im)≈Hk,p(i0), m=1 ..., Nc, Nc>NpFor the correlated time of channel corresponding OFDM symbol number of equal value,
In：
According to the reception pilot matrix after the cascade in the coherence time：
Obtaining the LS channel estimation results based on frequency pilot sign within the correlated time of channel is：
Wherein,ForPseudoinverse.
4. method as claimed in claim 3, which is characterized in that described that pilot tone is based within the correlated time of channel to the acquisition
The LS channel estimation of symbol is as a result, perform linear interpolation, with the channel estimation results of estimated data symbol position,
Further comprise：
The concretely comprising the following steps to the channel estimation of the data symbol position to be estimated in time domain：
Hk,data(l ')=α1×Hk,p,LS(l)+β1×Hk,p,LS(l+Δl)
The wherein when Domain Index of l ' expressions Data Position to be estimated, and there is l ＜ l ' ＜ l+ Δs l, l to represent pilot signal in the time domain
Position, Δ l represent the time domain interval of two adjacent pilot signals of time domain, and k represents subcarrier sequence number where pilot signal,
Interpolation coefficient α1, β1It calculates by the following method
And
The step of in frequency domain to the channel state information on the Data Position frequency domain index to be estimated, it is specially：
Hk′(l)=α2×Hk,S(l)+β2×Hk+Δk,S(l),S∈[p,data]；
The wherein frequency domain index of k ' expressions Data Position to be estimated, and there is k ＜ k ' ＜ k+ Δs k, k to represent pilot signal in a frequency domain
Position, Δ k represent the frequency interval of two adjacent pilot signals of frequency domain, interpolation coefficient α2, β2It calculates by the following method
5. method as claimed in claim 4, which is characterized in that it is described according in the correlation time based on frequency pilot sign most
Small two multiply channel estimation results, calculate the frequency pilot sign Noise Variance Estimation value on sub-carriers, be specially：
Wherein | | Hk,p,LS(im+1)-Hk,p,LS(im)||FRepresent Frobenius norms, im+1,imRepresent same Pilot OFDM symbols
Upper adjacent pilot frequencies subcarrier sequence number, final Noise Variance Estimation value are expressed from the next：
Wherein M is the occupied total number of sub-carriers of frequency pilot sign.
6. method as claimed in claim 5, which is characterized in that described that correlation time is obtained according to the Noise Variance Estimation value
Interior statistical channel status information, the statistical channel status information include the channel average and the channel covariancc, tool
Body includes：
According to the correlation time of communication channel, time domain sliding window length L is selected, wherein the sliding window length corresponds to subframe in sliding window
Including number of pilot symbols, according to the correlation bandwidth of channel, in the M that frequency domain is included from each coherence bandwidth0A pilot tone carries
The channel estimation results of ripple calculate moment i'sThe average of a channel state information：
And covariance：
WhereinVec () is represented matrix vector, ()HRepresent conjugate transposition.
7. method as claimed in claim 6, which is characterized in that it is described according to the channel average and channel covariancc, it calculates
Pre-coding matrix further comprises：
The system channel average obtained according to estimationChannel covariancc
And noise varianceThe influence of noise is added in into channel averageWith channel covariancc ΦH, obtain new channel averageAnd channel covarianccWherein：
Wherein noise covariance matrix
According toAnd ΦH,n, calculating matrixWherein
Wherein X[i,j]I-th j dimension for representing X is Nr×NrSub- square；
By matrix Z(s)Cholesky decomposition is carried out, obtains matrix L(s)：
Z(s)=L(s)·(L(s))H；
To L(s)Matrix carries out singular value decomposition：
Obtain Z(s)Eigenvalues Decomposition expression formula
Pre-coding matrix based on average Signal to Interference plus Noise Ratio criterion calculates by the following method
Wherein
WhereinIt is matrixR
Nonzero eigenvalue, μ are the water filling factor, and P is that transmitting terminal carries all subcarriers of user data and transmitting antenna transmit power
Summation.
8. the method as described in claim 1, which is characterized in that use the signal that receiving terminal receives after precoding for：
Yk(l)=Hk(l)·B·Xk(l)+Wk(l)
Wherein
Estimate to obtain the channel state information H of non-pilot character position by time domain and frequency domain two-dimensional linear interpolationk(l), with reference to institute
Pre-coding matrix B is stated, determines equivalent channel matrix HE,k(l), i.e.,
HE,k(l)=Β Hk(l)
According to equivalent combined channel matrix HE,k(l) using least mean-square error as criterion, receiving terminal carries out solution precoding and MIMO
The joint-detection of detection receives
9. a kind of pre-coding apparatus, which is characterized in that described device includes：
Receiving unit, for receiving the pilot signal of transmitting terminal transmission；
Estimation unit, for carrying out channel state information estimation according to uplink and downlink pilot signal, to obtain channel average and channel
Covariance；
Computing unit, for according to the channel average and channel covariancc, calculating pre-coding matrix；
Feedback unit, for giving the precoding matrix feedback to the transmitting terminal when uplink and downlink channel is unsatisfactory for symmetry,
In order to which the transmitting terminal carries out precoding according to the pre-coding matrix for the data-signal that needs are sent；
Decoding unit, for according to the pre-coding matrix, solution precoding to be carried out to the data-signal received.
10. pre-coding apparatus as claimed in claim 9, which is characterized in that the estimation unit is specifically used for：
The channel status that pilot frequency symbol position is carried out to the pilot signal received is estimated, to obtain the base within the correlated time of channel
In the LS channel estimation result of frequency pilot sign；
The LS channel estimation based on frequency pilot sign within the correlated time of channel is obtained as a result, performing in linear to described
Insert, with obtain data to be estimated channel estimation results on sub-carriers；
According to the LS channel estimation based on frequency pilot sign in the correlation time as a result, where calculating the frequency pilot sign
Noise Variance Estimation value on subcarrier；
Statistical channel status information in correlation time, the statistical channel state letter are obtained according to the Noise Variance Estimation value
Breath includes the channel average and the channel covariancc.
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| CN105099529B (en) * | 2015-06-30 | 2018-12-07 | 上海华为技术有限公司 | A kind of method and relevant device of data processing |
| CN105162504B (en) * | 2015-09-21 | 2019-01-29 | 华南理工大学 | A kind of quick mimo system transmitting terminal method for precoding |
| US11381287B2 (en) | 2017-06-16 | 2022-07-05 | Huawei Technologies Co., Ltd. | NR uplink codebook configuration method and related device |
| CN107483088B (en) | 2017-08-31 | 2021-05-04 | 东南大学 | Large-scale MIMO robust precoding transmission method |
| CN109787664A (en) | 2017-11-15 | 2019-05-21 | 索尼公司 | For the electronic equipment of wireless communication system, method, apparatus and storage medium |
| CN109842580B (en) * | 2017-11-28 | 2021-02-12 | 华为技术有限公司 | Channel estimation method and related equipment |
| US11496198B2 (en) | 2017-12-09 | 2022-11-08 | Huawei Technologies Co., Ltd. | Channel measurement method and user equipment |
| CN109194377B (en) * | 2017-12-09 | 2020-04-21 | 华为技术有限公司 | Channel measurement method and user equipment |
| CN109905154A (en) | 2017-12-09 | 2019-06-18 | 华为技术有限公司 | Channel measuring method and user equipment |
| CN110324070B (en) * | 2018-03-31 | 2022-08-26 | 华为技术有限公司 | Communication method, communication device and system |
| CN110365380B (en) * | 2018-04-10 | 2021-12-14 | 成都华为技术有限公司 | Data transmission method, communication device and system |
| CN109474387A (en) * | 2018-12-07 | 2019-03-15 | 东南大学 | A kind of joint detection algorithm applied to extensive MIMO uplink |
| CN110611895B (en) * | 2019-09-25 | 2020-10-09 | 西京学院 | Indoor positioning method based on four-dimensional code mapping |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101400117A (en) * | 2007-09-27 | 2009-04-01 | 联想（上海）有限公司 | Downlink channel status information determining method and apparatus, pre-coding method and apparatus |
| CN101630967A (en) * | 2009-08-12 | 2010-01-20 | 中兴通讯股份有限公司 | Method for obtaining channel quality in multi-input multi-output system |
| CN101909022A (en) * | 2010-06-24 | 2010-12-08 | 北京邮电大学 | Transmission method based on non-codebook based precoding in time-varying channel |
| CN102271026A (en) * | 2011-07-27 | 2011-12-07 | 东南大学 | Closed-loop self-adaptive transmission method used for uplink of advanced long-term evolution system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8619542B2 (en) * | 2010-01-15 | 2013-12-31 | Motorola Mobility Llc | Closed-loop feedback in wireless communications system |
-
2013
- 2013-12-04 CN CN201310648796.7A patent/CN104702543B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101400117A (en) * | 2007-09-27 | 2009-04-01 | 联想（上海）有限公司 | Downlink channel status information determining method and apparatus, pre-coding method and apparatus |
| CN101630967A (en) * | 2009-08-12 | 2010-01-20 | 中兴通讯股份有限公司 | Method for obtaining channel quality in multi-input multi-output system |
| CN101909022A (en) * | 2010-06-24 | 2010-12-08 | 北京邮电大学 | Transmission method based on non-codebook based precoding in time-varying channel |
| CN102271026A (en) * | 2011-07-27 | 2011-12-07 | 东南大学 | Closed-loop self-adaptive transmission method used for uplink of advanced long-term evolution system |
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