CN101277172A - Method, apparatus and system for generating precoding matrix - Google Patents

Abstract

The invention discloses a pre-coding matrix generation method which includes steps: a user terminal selects pre-coding vector in pre-set nonorthogonal codebook; the user terminal transmits selected pre-coding vector to a network side; the network side generates pre-coding matrix according with pre-coding vector transmitted by the user terminal. The invention also discloses a pre-coding matrix generating system. Pairing success probability of the network side is increased by using design scheme based on nonorthogonal grouping codebook.

Description

A kind of pre-coding matrix generates methods, devices and systems

Technical field

The present invention relates to communication technical field, relate in particular to the pre-coding matrix generation technique in a kind of MIMO (Multiple Input MultipleOutput, multiple-input and multiple-output) system.

Background technology

Exigent transmission rate of next generation wireless communication and lower transmitting power, but be faced with the challenge of limited frequency spectrum resources and abominable transmission environment.When many antennas are introduced in network side base station end and mobile you simultaneously, to tie up this three-dimensional resource except time dimension, frequency domain dimension, sign indicating number territory, the resource of space dimension can be utilized and be developed.Therefore, MU-MIMO (Multi-User MIMO, multiuser MIMO) technology becomes when previous hot issue thereupon.The MIMO technology has the incomparable advantage of other technologies at aspects such as supporting high speed data transfer, the raising availability of frequency spectrum and power efficiency, has caused huge concern at wireless communication field.The MU-MIMO system utilizes SDMA (Space DivisionMultiple Access, spatial reuse) technology can transmit a plurality of user's data streams at one time with on the frequency resource, and SU-MIMO (Single-User MIMO, Single User MIMO) utilizes space multiplexing technique to transmit a user's data stream at one time with on the frequency resource.In the MU-MIMO system, base station while and a plurality of travelling carriage communicate, can obtain multi-user diversity gain and figuration gain simultaneously by sending figuration, system compares with Single User MIMO, can improve its power system capacity and spectrum efficiency, but the interference that how to suppress between the multi-user is an important topic.

LTE (Long Term Evolution, Long Term Evolution) the MU-MIMO scheme PU2RC that is proposed in (Per-User Unitary Rate Control, the control of user's single-rate) at 3GPP (3rdGeneration Partnership Project, third generation partner program) in as the candidate scheme of HSDPA (HighSpeed Downlink Packet Access, high-speed downlink packet insert) enhancement techniques.The MU-MIMO technology sends figuration at transmitting terminal to the user who is transmitted usually, the corresponding figuration vector of each user.Transmission figuration technology in the MU-MIMO system can improve its channel gain, and in the interference that suppresses under the less situation of the coefficient correlation between user's figuration vector between the multi-user.The MU-MIMO system that has occurred the pre-coding matrix of Unitary (quadrature) at present.Each pre-coding matrix of this scheme all is a square formation, and promptly precoding vector number in each pre-coding matrix and transmitting antenna number equate, and vectorial orthogonal in the pre-coding matrix, can effectively reduce multi-user interference.But at FDD (FrequencyDivision Duplex, mode of frequency division duplexing) under the limited situation of feedback quantity, because each user can only feed back a small amount of SINR (Signal to Interference plus Noise Ratio, signal and interference plus noise power ratio) information, this moment, the pairing probability of Unitary scheme was lower when network equipment is dispatched and matched.

Prior art discloses a kind of scheme of utilizing user feedback to select the Unitary precoding vector.In this scheme, each user carries out choosing of precoding vector based on the channel matrix of oneself, sequence number with selected precoding vector feeds back to the base station again, is found out corresponding precoding vector and the user of a shared time is carried out precoding by the base station to send.This scheme can reduce multi-user interference greatly, but when the FDD feedback quantity is limited, because the precoding vector number of each user feedback is limited, causes the pairing probability of this scheme still lower equally.

Summary of the invention

Embodiments of the invention provide a kind of pre-coding matrix to generate methods, devices and systems, to solve the lower defective of successful matching probability of multi-user MIMO system in the prior art.

For achieving the above object, embodiments of the invention provide a kind of pre-coding matrix generation method, may further comprise the steps:

User terminal is selected precoding vector in predefined nonopiate code book;

Described user terminal sends to network side with described precoding vector;

Described network side generates pre-coding matrix according to the precoding vector that user terminal sends.

Embodiments of the invention also provide a kind of user terminal, comprise that precoding vector chooses the unit, store predefined nonopiate code book, and should nonopiate code book offer described precoding vector and choose the unit.

Embodiments of the invention also provide a kind of network equipment, comprise scheduling unit, receive the precoding vector that each user terminal selects in predefined nonopiate code book after, choose several user terminal precoding vectors combinations and generate pre-coding matrix.

Embodiments of the invention also provide a kind of wireless communication system, comprise user terminal and network equipment,

Described user terminal is selected precoding vector in predefined nonopiate code book, and described precoding vector is sent to described network equipment;

Described network equipment generates pre-coding matrix according to the precoding vector that each described user terminal sends.

Compared with prior art, embodiments of the invention have the following advantages:

Embodiments of the invention have proposed pre-coding matrix generation methods, devices and systems in a kind of multi-user MIMO system, adopt based on the non-orthogonal codes present design, have improved the probability of success of pairing.

Description of drawings

Fig. 1 is the flow chart of pre-coding matrix generation method in the embodiments of the invention one;

Fig. 2 is the schematic diagram that the network equipment is dispatched user terminal in the embodiments of the invention two;

Fig. 3 is at FDD 22 power system capacity schematic diagrames of receiving distinct methods under the antenna configurations when feedback is limited in the embodiments of the invention three;

Fig. 4 is at FDD 84 power system capacity schematic diagrames of receiving distinct methods under the antenna configurations when feedback is limited in the embodiments of the invention three;

Fig. 5 is the structural representation of pre-coding matrix generation system in the embodiments of the invention four.

Embodiment

Below in conjunction with drawings and Examples, embodiments of the present invention are described further.

In the embodiments of the invention one, a kind of pre-coding matrix generation method may further comprise the steps as shown in Figure 1:

Step s101, nonopiate code book is divided into groups based on predefined vectorial number, and any two vectors in the calculating group, be the right relative coefficient of each vector and.

In this step, be example with the nonopiate code book based on the Grassmannian criterion, the standard that the vector in the nonopiate code book of Grassmannian is divided into groups is the correlation of different vectors in the code book, any two vector v _iWith v _jCorrelation can be by calculating v _i ^Hv _jValue and compared, the more little then correlation of the value that obtains is more little, on the contrary correlation is big more.During grouping, the not interior on the same group vectorial number and the number of transmit antennas of network equipment or user terminal are irrelevant, can be any number, in the present embodiment, the scheme of taking is the stepped risings of vectorial number in the different precoding codebook groups, as the vectorial number in the different precoding codebook groups be respectively 2,4,8,16... or 2,3,5,7,10... etc.After the grouping, vector in each group and vectorial position and a number average immobilize, and promptly precoding codebook all immobilizes for network side controlling equipment and user terminal.

In calculating different groups, during the right relative coefficient summation of vector, be divided into two kinds of situations:

Situation 1:L≤M, wherein L is the vectorial number in the Vector Groups, and M is the number of transmit antennas of network equipment, and the number of vector is less than or equal to number of transmit antennas in the Vector Groups that promptly needs to search for.

In this case, a Vector Groups is made of L vector, is M * N in size _t(M is a number of transmit antennas, N _tBe vector sum in the nonopiate code book of Grassmannian) the nonopiate code book of Grassmannian in get one group of L vector composition arbitrarily, i.e. figuration matrix w, w=[v ₁v ₂..., v _L], total

Group, and calculate in each Vector Groups the right coefficient correlation of vector and, this coefficient correlation and be:

${\mathrm{\ρ}}_{\mathrm{sum}}=\underset{i+1}{\overset{L}{\mathrm{\Σ}}}\underset{j=i+1}{\overset{L}{\mathrm{\Σ}}}{\mathrm{\ρ}}_{i,j}$

${\mathrm{\ρ}}_{i,j}=v_i^H{v}_j$

Vector Groups with the needs search comprises that L=2 vector, number of transmit antennas M=3 are example, then comprises N one _tIn the precoding codebook of=4 vectors, select figuration matrix w=[v ₁v ₂] method total $C_{}^{}$ ${}_4^2=6$ Kind.

Situation 2:L＞M, wherein L is the vectorial number in the Vector Groups, and M is a number of transmit antennas, and the number of vector is more than or equal to its number of transmit antennas in the Vector Groups that promptly needs to search for.

In this case, not only to divide into groups and the compute vector group in the right coefficient correlation of vector and, and in order to guarantee the isotropism of vector, and guarantee the pairing probability to the coefficient correlation size, this moment need be to ρ _{I, j}Set thresholding and search for, that is:

${\mathrm{\ρ}}_{\mathrm{sum}}=\underset{i+1}{\overset{L}{\mathrm{\Σ}}}\underset{j=i+1}{\overset{L}{\mathrm{\Σ}}}{\mathrm{\ρ}}_{i,j}$

${\mathrm{\&rho;}}_{i,j}=v_i^H{v}_j,{\mathrm{\&rho;}}_0<{\mathrm{\&rho;}}_{i,j}<{\mathrm{\&rho;}}_1$

ρ ₀And ρ ₁Be the threshold value that more on average sets for the vectorial right coefficient correlation size in the Vector Groups that guarantees to search for out, this threshold value is an empirical value, by setting this threshold value, makes that the right coefficient correlation of arbitrary vector is in thresholding ρ in the Vector Groups ₀And ρ ₁In, by thresholding ρ is set ₀And ρ ₁Value can guarantee vectorial number in each Vector Groups.

Step s102, user terminal carry out choosing of pre-coding matrix according to the coefficient correlation summation between the vector in each group of grouping back.

According to calculating the coefficient correlation summation between the vector in each good group, in advance each group is sorted, when choosing Vector Groups, user terminal carries out according to the minimum principle of coefficient correlation summation, each group of choosing constitutes a pre-coding matrix, the pre-coding matrix that constitutes is ladder, and a plurality of pre-coding matrixes constitute complete precoding codebook.

For example to constitute the figuration matrix of n=2 M * L, then in above calculating gained result, choose and have minimum ρ _SumValue and time little ρ _Sum2 Vector Groups of value are as 2 figuration matrix w1 that select for use and w2.

For example will constitute n=2 figuration matrix, one of them is the Vector Groups of M * L, and another one is the Vector Groups of M * (2L), then chooses to have minimum ρ in above calculating gained result _SumValue M * L Vector Groups and minimum ρ _SumThe Vector Groups of the M of value * (2L) is as 2 figuration matrix w that select for use ₁And w ₂

In addition, if only need to produce the figuration matrix of a M * L, can directly utilize the code book of Grassmannian M * L dimension.

Step s103, user terminal feed back the sequence number of one or more precoding vectors based on each pre-coding matrix, and the corresponding SINR value of this precoding vector is dispatched for network equipment.

Behind correlation generation pre-coding matrix, the user feeds back one or more precoding vectors and corresponding SINR value thereof based on each precoding vector group, and the choice criteria of precoding vector is the size of SINR value during feedback.After network equipment receives the precoding vector of each user terminal, preferentially remove to generate user's pre-coding matrix based on the little Vector Groups of correlation.

Step s104, network side generate pre-coding matrix according to the precoding vector that each user terminal sends.

Specific embodiment when embodiments of the invention two are applied to mimo system for the precoding design with nonopiate code book.

With the nonopiate code book based on the Grassmannian criterion is example, has preestablished a precoding codebook based on the nonopiate code book of Grassmannian at network equipment and UE (UserTerminal, user terminal) end, comprising n pre-coding matrix.At first, each UE end need according to set in the precoding codebook pre-coding matrix and according to the resulting channel matrix H of channel estimating _kCalculate, obtain the value of the pairing SINR of each precoding vector in each pre-coding matrix.If number of transmit antennas is M, the reception antenna number is N, then H _kFor:

$H_k=\left[\begin{array}{cccc}{\mathrm{<figure-callout\; id="1"\; label="H"\; filenames="A20071009099000152.png,A20071009099000161.png"\; state="\{\{state\}\}">H</figure-callout>}}_{\mathrm{1,1}}& {\mathrm{<figure-callout\; id="2"\; label="H"\; filenames="A20071009099000152.png,A20071009099000161.png"\; state="\{\{state\}\}">\; <figure-callout\; id="1"\; label="H"\; filenames="A20071009099000152.png,A20071009099000161.png"\; state="\{\{state\}\}">H</figure-callout>\; </figure-callout>}}_{\mathrm{2,1}}& ...& {\mathrm{<figure-callout\; id="1"\; label="H"\; filenames="A20071009099000152.png,A20071009099000161.png"\; state="\{\{state\}\}">H</figure-callout>}}_{1,\mathrm{<figure-callout\; id="2"\; label="M\; H"\; filenames="A20071009099000152.png,A20071009099000161.png"\; state="\{\{state\}\}">M</figure-callout>}}& \\ H_{}{}_{\mathrm{2,1}}& {\mathrm{<figure-callout\; id="2"\; label="H"\; filenames="A20071009099000152.png,A20071009099000161.png"\; state="\{\{state\}\}">\; <figure-callout\; id="2"\; label="H"\; filenames="A20071009099000152.png,A20071009099000161.png"\; state="\{\{state\}\}">H</figure-callout>\; </figure-callout>}}_{\mathrm{2,2}}& ...& {\mathrm{<figure-callout\; id="2"\; label="H"\; filenames="A20071009099000152.png,A20071009099000161.png"\; state="\{\{state\}\}">H</figure-callout>}}_{2,M}\\ ...& ...& ...& ...\\ H_{N,1}& H_{N,2}& ...& H_{N,M}\end{array}\right]$

Wherein, H _{I, j}Be that the j transmit antennas is corresponding to the channel impulse of i root reception antenna.

$H_{i,j}\left(\mathrm{\&tau;}\right)={\mathrm{\&Sigma;}}_{n=1}^L{A}_n\mathrm{\&delta;}(\mathrm{\&tau;}-{\mathrm{\&tau;}}_n)$

L is the number of multipath; A _nIt is the amplitude in n bar footpath; δ (g) represents impulse function; τ _nIt is the time delay in n bar footpath.

If adopt LMMSE (Linear Minimum Mean Squared Error, linear minimum mean-squared error) input at the UE end, then under the LMMSE criterion, receiving matrix satisfies

$G_k={({\tilde{H}}_k^{*}H+\frac{{\mathrm{\&sigma;}}^2}{P_k}I)}^{-1}{\tilde{H}}_k^{*}$

${\tilde{H}}_k^{*}=H_{k}w$

Wherein, w is a pre-coding matrix.H _kThe mimo channel matrix of representing k user, G _kThe receiving matrix of representing k user.P _kFor the transmitted power on the single antenna is k user's a transmitted power, σ ²The expression noise variance.

At the UE end, after i precoding vector among the employing pre-coding matrix w carried out precoding, the Signal to Interference plus Noise Ratio SINR of i data flow was:

${\mathrm{SINR}}_i=\frac{P_i{\left|{\tilde{G}}_i{\tilde{h}}_i\right|}^2}{P\underset{j=1,j\&NotEqual;i}{\overset{L}{\mathrm{\&Sigma;}}}{\left|{\tilde{G}}_i{\tilde{h}}_i\right|}^2+{\left|{\tilde{G}}_i\right|}^2{\mathrm{\&sigma;}}^2}$

Wherein, It is matrix

In i row, L is the precoding vector number among the pre-coding matrix w.Under LMMSE detects, have

${\tilde{G}}_i={\tilde{h}}_i^{*}{({\tilde{H}}_i{\tilde{H}}_i^{*}+\frac{{\mathrm{\&sigma;}}_2}{p_i})}^{-1}$

Concerning user k, known channel matrix H at the UE end _kBehind pre-coding matrix w, can calculate the value of a corresponding SINR at the figuration vector in each figuration matrix.

Therefore, have n pre-coding matrix w for one ₁... w _n, and comprise L in i pre-coding matrix _iThe precoding codebook of individual precoding vector, each user needs to calculate altogether

The value of individual SINR, in respectively corresponding n the pre-coding matrix The SINR of individual precoding vector.Under the unity feedback situation, each user need be with this

The value of individual SINR all feeds back to network equipment and dispatches for network equipment.And under the restricted situation of FDD feedback quantity, each UE can only feed back a small amount of SINR and each SINR corresponding sequence number is returned network equipment.

As shown in Figure 2, network equipment is after receiving these feedback informations, an equity X to be scheduled user dispatches, scheduler Scheduler chooses K user by maximum capacity standard or other standards from X user, this K user's precoding vector is combined as pre-coding matrix w transmits.Each user's data stream after choosing also will carry out each user's data stream to merge transmission after the precoding through precoder Precoder.Then k the user's who receives at receiving terminal signal is:

$y_k=\sqrt{P}{H}_k\mathrm{ws}+n_k,k=1,...,k$

w＝[v ₁?v ₂?...?v _K]

$\underset{k=1}{\overset{K}{\mathrm{\&Sigma;}}}{P}_k={\mathrm{<figure-callout\; id="0"\; label="P"\; filenames="A20071009099000161.png"\; state="\{\{state\}\}">P</figure-callout>}}_0$

s＝[s ₁?s ₂?...?s _K] ^T

$y_k=\sqrt{P}{H}_k\underset{k=1}{\overset{K}{\mathrm{\&Sigma;}}}{v}_i{s}_i+n_k,k=1,...,k$

Wherein, M is a number of transmit antennas, and N is the reception antenna number, H _kChannel fading for user k experience is the channel matrix of N * M.y _k∈ C ^NBe k the signal vector that the user receives, s ∈ C ^KBe the transmission signal vector of K data flow, w ∈ C ^{M * K}Be the pre-coding matrix of MIMO, n _k∈ C ^NBe additive white Gaussian noise, P _kBe the transmitted power of k data flow, P ₀It is the transmitted power of all data flow.

Then UE is brought in, if adopt LMMSE to detect, k user detects the data that obtain and is:

${\hat{s}}_k={\tilde{G}}_k{y}_k,k=1,...,K$

The embodiment of the invention two part unlike the prior art is the design of precoding codebook, quoted nonopiate code book as precoding codebook, the precoding codebook that the pre-coding matrix that this vector number increases progressively constitutes is compared with the precoding codebook that the Unitary pre-coding matrix that is square formation constitutes, under the limited situation of FDD power system capacity, be the pairing probability height of the Unitary precoding multi-user MIMO system of square formation than pre-coding matrix.On the packet mode of pre-coding matrix, on the same group in the number of vector can be not identical yet, but successful matching probability in this case do not have not on the same group in the successful matching probability height of vectorial number when increasing progressively.

Embodiments of the invention three embodiment for matching at FDD UE and network equipment under the limited situation of feedback.

Suppose FDD under the limited situation of feedback, all only with the value of a SINR, and the Index (sequence number) of the precoding vector correspondence of this SINR correspondence feeds back to network equipment to each user for each pre-coding matrix.Network equipment has M root transmitting antenna, and the ladder precoding codebook that this programme is selected for use comprises n pre-coding matrix.Vector length in i pre-coding matrix is L _i, then each UE can feed back n SINR with and corresponding Index return network equipment.Network equipment receives that selecting K user according to certain standard such as maximum capacity criterion behind user's the feedback information dispatches, if send K user's information altogether, then each figuration matrix is all selected the user of K maximum SINR correspondence, and whether the Index i that judges this K user is identical, if different, then successful matching concerning this figuration matrix; If identical, then pairing failure concerning this figuration matrix.When a figuration matrix successful matching was wherein arranged, the whole proposal successful matching was when neither one figuration matrix can successful matching, then whole proposal pairing failure.Therefore, scheme successful matching probability P _SuccessEqual 1 and deduct pairing probability of failure P _Fail:

P _success＝1-P _fail

The pairing probability of failure all matches probability of failure for all figuration matrixes, is following formula:

$P_{\mathrm{fail}}=P_{\mathrm{fail}}^1\&times;P_{\mathrm{fail}}^2\&times;\&CenterDot;\&CenterDot;\&CenterDot;\&times;P_{\mathrm{fail}}^n$

P wherein _Fail ⁱRepresent i matrix pairing failed probability.

$P_{\mathrm{fail}}^i=1-P_{\mathrm{success}}^i$

$P_{\mathrm{success}}^i=\frac{P_{L_i}^K}{L_i^K}=\frac{L_i\&times;(L_i-1)\&times;(L_i-2)\&times;\&CenterDot;\&CenterDot;\&CenterDot;\&times;(L_i-K+1)}{L_i^K}$

L _iRepresent the vectorial number in i the figuration matrix.

$P_{\mathrm{success}}=1-{\mathrm{<figure-callout\; id="1"\; label="P\; fail"\; filenames="A20071009099000152.png,A20071009099000161.png"\; state="\{\{state\}\}">P</figure-callout>}}_{\mathrm{fail}}^{}\&times;P_{\mathrm{fail}}^2\&times;\&CenterDot;\&CenterDot;\&CenterDot;\&times;P_{\mathrm{fail}}^n=1-\underset{i=1}{\overset{n}{\mathrm{\&Pi;}}}(1-P_{\mathrm{success}}^1)=1-\underset{i=1}{\overset{n}{\mathrm{\&Pi;}}}(1-\frac{P_{L_i}^K}{L_i^K})$

For example:

Be set to 2 * 2 at antenna, figuration matrix number n=2 send under the K=2 user situation, and the size of stair-stepping figuration matrix is respectively 2 * 2 and 2 * 4.

$P_{\mathrm{success}\_\mathrm{unitary}}=1-\underset{i=1}{\overset{n}{\mathrm{\&Pi;}}}(1-\frac{P_{L_i}^K}{L_i^K})=1-(1-\frac{2}{4})(1-\frac{2}{4})=\frac{3}{4}$

$P_{\mathrm{success}\_\mathrm{nonunitary}}=1-\underset{i=1}{\overset{n}{\mathrm{\&Pi;}}}(1-\frac{P_{L_i}^K}{L_i^K})=1-(1-\frac{2}{4})(1-\frac{4\&times;3}{4\&times;4})=\frac{7}{8}$

P _{Success_unitary}The probability of expression Unitary (quadrature) scheme successful matching; P _{Sucess_nonunitary}The probability of expression this programme successful matching.As shown in Figure 3, the embodiment of the invention has improved 0.125 than Unitary scheme pairing probability, and performance loss is less than 1bps/Hz under identical signal to noise ratio.With respect to the SU-MIMO scheme, it is more that the pairing probability improves.

Be set to 8 * 4 at antenna, figuration matrix number n=2 send under the K=8 user situation, and the size of stair-stepping figuration matrix is respectively 8 * 8 and 8 * 16.

$P_{\mathrm{success}\_\mathrm{unitary}}=1-\underset{i=1}{\overset{n}{\mathrm{\&Pi;}}}(1-\frac{P_{L_i}^K}{L_i^K})=1-(1-\frac{8!}{8^8})(1-\frac{8!}{8^8})=0.0048$

$P_{\mathrm{success}\_\mathrm{nonunitary}}=1-\underset{i=1}{\overset{n}{\mathrm{\&Pi;}}}(1-\frac{P_{L_i}^K}{L_i^K})=1-(1-\frac{8!}{8^8})(1-\frac{32!}{{32}^8})=0.3872$

This moment, the pairing probability of orthogonal scheme was quite little, approached 0, but not the orthogonal scheme probability promotes very greatly 0.3824, and performance loss is less than 2bps/Hz, as shown in Figure 4 under identical signal to noise ratio.

By using the pre-coding matrix generation method that the foregoing description provided, make that under the limited situation of FDD system feedback amount the precoding codebook owing to having adopted based on nonopiate code book can improve the successful matching probability.Above embodiment is example explanation embodiments of the present invention with the nonopiate code book of Grassmannian just, and the scope of nonopiate code book only is not limited in the nonopiate code book based on the Grassmannian criterion.

In the embodiments of the invention four, having proposed a kind of wireless communication system, is that the base station is an example with the network equipment, comprises a plurality of user terminals 10 and base station 20,

User terminal 10 comprises that precoding codebook memory cell 11, precoding vector choose unit 12 and terminal transmitting element 13.

Wherein, precoding codebook memory cell 11, storage is based on the precoding codebook of nonopiate code book, comprising a plurality of pre-coding matrixes are arranged, and this precoding codebook is offered precoding vector chooses unit 12.

Precoding vector is chosen unit 12, nonopiate code book is divided into groups based on predefined vectorial number, the right relative coefficient of compute vector and; Choose at least one pre-coding matrix according to the right relative coefficient summation of each vector, feed back one or more precoding vectors and corresponding SINR value thereof based on each pre-coding matrix, with the sequence number of precoding vector and accordingly the SINR value send to terminal transmitting element 13.

Terminal transmitting element 13 passes through a day alignment base station transmission with the sequence number and the corresponding SINR value thereof of precoding vector.

Base station 20 comprises receiving element 21, scheduling unit 22, precoding unit 23 and transmitting element 24.

Receiving element 21 receives the sequence number and the corresponding SINR value thereof of the selected pre-coding matrix of user terminal that user terminal sends, and with these information to scheduling unit 22 transmissions.

Scheduling unit 22 is after receiving these information, equity each user terminal to be scheduled is dispatched, scheduling unit 22 is chosen K user terminal by certain standard from X user terminal, the precoding vector of this K user terminal is combined as pre-coding matrix w transmits.

Merging was sent to transmitting element 24 after each user's data stream that precoding unit 23 is chosen scheduling unit 22 carried out precoding.

Transmitting element 24 sends to each user terminal with the data flow after the precoding.

By pre-coding matrix generation system and the device that uses above embodiment to provide, make under the limited situation of FDD system feedback amount, owing to adopted precoding codebook based on nonopiate code book, improved matching probability, improved the resource utilization of network side controlling equipment.

More than disclosed only be several specific embodiment of the present invention, still, the present invention is not limited thereto, any those skilled in the art can think variation all should fall into protection scope of the present invention.

Claims (13)

1. a pre-coding matrix generation method is characterized in that, comprising:

User terminal is selected precoding vector in predefined nonopiate code book;

Described user terminal sends to network side with described precoding vector;

Described network side generates pre-coding matrix according to the precoding vector that user terminal sends.

2. pre-coding matrix generation method according to claim 1 is characterized in that described user terminal also comprises select precoding vector in described nonopiate code book before:

Described user terminal and described network side divide into groups described nonopiate code book based on predefined vectorial number.

3. as pre-coding matrix generation method as described in the claim 2, it is characterized in that, after this grouping of described non-orthogonal codes, on the same group in the number of vector not identical or different.

4. as pre-coding matrix generation method as described in the claim 2, it is characterized in that described user terminal selects precoding vector specifically to comprise in predefined nonopiate code book:

Described user terminal selects at least one Vector Groups as pre-coding matrix according to the right relative coefficient summation of vector in described each grouping;

Described user terminal is respectively chosen at least one precoding vector in each pre-coding matrix of described selection.

5. as pre-coding matrix generation method as described in the claim 4, it is characterized in that the right relative coefficient of vector and being specially in the described grouping:

As the number L of vector in the Vector Groups when being less than or equal to the number of transmit antennas M of described network side, described coefficient correlation and be:

${\mathrm{\&rho;}}_{\mathrm{sum}}=\underset{i+1}{\overset{L}{\mathrm{\&Sigma;}}}\underset{j=i+1}{\overset{L}{\mathrm{\&Sigma;}}}{\mathrm{\&rho;}}_{i,j}$

${\mathrm{\&rho;}}_{i,j}=v_i^H{v}_j$

Wherein, v is the vector among the figuration matrix w, w=[v ₁v ₂... v _L], w is by M * N _tNonopiate code book code book in get arbitrarily L vector form N _tBe the vector sum in the grouping code book;

As the number L of vector in the Vector Groups during greater than the number of transmit antennas M of described network side, described coefficient correlation and be:

${\mathrm{\&rho;}}_{\mathrm{sum}}=\underset{i+1}{\overset{L}{\mathrm{\&Sigma;}}}\underset{j=i+1}{\overset{L}{\mathrm{\&Sigma;}}}{\mathrm{\&rho;}}_{i,j}$

${\mathrm{\&rho;}}_{i,j}=v_i^H{v}_j,$ ρ ₀＜ρ _i，j＜ρ ₁

Wherein, ρ ₀And ρ ₁It is predefined threshold value.

6. as pre-coding matrix generation method as described in the claim 4, it is characterized in that described user terminal selects at least one Vector Groups to be specially as pre-coding matrix according to right relative coefficient summation of vector in described each grouping,

According to the right relative coefficient summation of vector in the group described each Vector Groups is sorted in advance, described user terminal is chosen one or more Vector Groups as pre-coding matrix from small to large according to described relative coefficient summation.

7. as pre-coding matrix generation method as described in the claim 4, it is characterized in that described user terminal is respectively chosen at least one precoding vector and is specially in each pre-coding matrix of described selection,

Described user terminal is selected precoding vector with interference plus noise power than the size of SINR value according to the signal of each precoding vector in the described pre-coding matrix.

8. as pre-coding matrix generation method as described in the claim 7, it is characterized in that described user terminal sends to network side with described precoding vector and is specially:

Described user terminal sends the sequence number of described precoding vector and the SINR value of described precoding vector based on described pre-coding matrix to network side.

9. as pre-coding matrix generation method as described in the claim 7, it is characterized in that the precoding vector that described network side sends according to each user terminal generates pre-coding matrix and is specially:

Described network side receives the precoding vector that user terminal sends;

Described network side is selected several user terminals from described user terminal;

Described network side is combined as described pre-coding matrix with the precoding vector of several user terminals transmissions of described selection.

10. a user terminal is characterized in that, comprises that precoding vector chooses the unit, in predefined nonopiate code book, selects and feeds back one or more precoding vectors and give network equipment.

11., it is characterized in that as user terminal as described in the claim 10, also comprise the precoding codebook memory cell, store predefined nonopiate code book, and should nonopiate code book offer described precoding vector and choose the unit.

12. a network equipment is characterized in that, comprises scheduling unit, receive the precoding vector that each user terminal selects in predefined nonopiate code book after, chooses several user terminal precoding vectors combinations and generates pre-coding matrix.

13. a wireless communication system comprises user terminal and network equipment, it is characterized in that,

Described user terminal is selected precoding vector in predefined nonopiate code book, and described precoding vector is sent to described network equipment;

Described network equipment generates pre-coding matrix according to the precoding vector that each described user terminal sends.

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