CN101630966A - Feedback method of channel quality in multi-input and multi-output system - Google Patents

Abstract

The invention discloses a feedback method of channel quality in a multi-input and multi-output system, by which a receiving terminal feeds channel quality information back to a transmission terminal. In the method, the receiving terminal estimates the influence of current interference to the channel quality according to past interference within a time interval ended at current time and feeds the channel quality information back to the transmission terminal after acquiring the channel quality information. Compared with the prior art, the receiving terminal in the feedback method can acquire more accurate channel quality information and feeds the channel quality information back to the transmission terminal when multiple layers of interference exist.

Description

The feedback method of channel quality in the multi-input multi-output system

Technical field

The present invention relates to wireless communication field, be specifically related to the feedback method of channel quality in a kind of multiple-input and multiple-output (MIMO) system.

Background technology

In radio communication, if use many antennas, then can take the mode of spatial reuse to improve transmission rate, i.e. the different antennae position emission different data of transmitting terminal on identical running time-frequency resource at transmitting terminal (eNB).(UE) also uses many antennas at receiving terminal, then the resource of all antennas all can be distributed to same user under single user's situation.This above transmission form is referred to as Single User MIMO (SU-MIMO).Also can give different user with the resource allocation in different antennae space under multi-user's situation in addition, this transmission form is called multiuser MIMO (MU-MIMO).

Above-mentioned Single User MIMO and multiuser MIMO both of these case, transmitting terminal all need the channel information (CSI) according to each user to come Resources allocation and decision method for transmitting.Receiving terminal can obtain out by channel estimating each dual-mode antenna between channel information, then feedback information is given eNB.

Under the situation of reality, because feedback is to need to use system resource, general UE quantizes information just to feed back.At Long Term Evolution (Long Time Evolution, LTE) in the system, the feedback system of the information after the quantification, mainly comprise CQI (Channel Quality Indicator, CQI), pre-coding matrix index (Precoding Matrix Index, PMI) indicate with order (RankIndicator, RI).In addition, transmitting terminal also can come estimating channel information from alternate manner, for example estimates descending channel information with channel reciprocity from up channel information.

Receiving terminal can calculate Signal to Interference plus Noise Ratio (SINR) by channel and Interference Estimation, CQI generally is exactly the SINR after quantizing, below be under the scene of SU-MIMO spatial reuse (Spatial Multiplexing), the computational methods of SINR during with least mean-square error (MMSE) receiver.

When transmitting terminal and receiving terminal all had 2 antennas, the channel between transmitting terminal and the receiving terminal was the matrix H of a 2x2, and when order was 2, precoding W also was the matrix of a 2x2, and the channel after the precoding processing then is:

F=[f ₁f ₂]=HW formula (1)

Wherein, f ₁Be the equivalent channel vector of ground floor, f ₂Equivalent channel vector for the second layer.

The signal that receiving terminal is received is the vectorial y of a 2x1, and n also is the vector of a 2x1, interference and the noise of representing 2 antennas to receive, and s ₁And s ₂Then be respectively data symbol at different numeral streams:

Y=f ₁s ₁+ f ₂s ₂+ n formula (2)

Using under the MMSE receiver situation, the Signal to Interference plus Noise Ratio (SINR) of numeral stream (stream) 1 and numeral stream 2 is respectively:

$\mathrm{stream}1=f_1^{*}{\hat{R}}_{\mathrm{nn},2}^{-1}{f}_1$ Formula (3)

$\mathrm{stream}2=f_2^{*}{\hat{R}}_{\mathrm{nn},1}^{-1}{f}_2$ Formula (4)

Wherein,

${\hat{R}}_{\mathrm{nn},k}=\underset{i}{\overset{\mathrm{nu}\min t}{\mathrm{\Σ}}}{H}_i{H_i}^{*}+f_k{f}_k^{*}+N_{o}I,$ Num int represents the number of interfered cell;

H _iBe presence of intercell interference (inter-cell interference);

H _i ^*Be H _iTransposed matrix;

N _oI is the white noise of Gaussian Profile;

Then

Be interference and noise covariance matrix, comprise the co-channel interference f between the numeral stream for k stream _k

For the LTE of Release 8, precoding all is predetermined from the code book of standard, and under the situation of SU-MIMO, SINR can accurately know the interference between the numeral stream when calculating, so also can more accurately calculate CQI.But under the dual-stream beamforming (Beamforming) that Release 9 supports, precoding is that receiving terminal calculates, and receiving terminal just can not accurately be known the interference between the numeral stream, and the calculating of CQI has deviation in the time of may be with actual transmission.

Under multi-user's double fluid Beamforming scene, when two users do spatial reuse, when being 2 with the SU-MIMO order, the account form of SINR compares, and just each numeral stream is to be occupied by different users, disturbs the interference that just can be said to the multi-user.

The signal of receiving at user's 1 receiving terminal is:

y＝f ₁s ₁+f ₂s ₂+n

When user's 1 usefulness MMSE receiver, user 1 Signal to Interference plus Noise Ratio (SINR) is:

$\mathrm{MMSESINRforUser}1=f_1^{*}{\hat{R}}_{\mathrm{nn},2}^{-1}{f}_1,$ Wherein ${\hat{R}}_{\mathrm{nn},k}=\underset{i}{\overset{\mathrm{numInt}}{\mathrm{\Σ}}}{H}_i{H_i}^{*}+f_k{f}_k^{*}+N_{o}I.$

Because different data are launched to the multi-user in the different antennae position of transmitting terminal on identical running time-frequency resource, each user can produce interference to other user.Though can reduce each user's interference with certain methods (for example broken zero etc.), under the situation of reality,, all can have certain multi-user interference to exist at receiving terminal because quantize and other various error.Having under the situation of multi-user interference, because multi-user's pairing is to carry out at transmitting terminal, receiving terminal generally is difficult to do the following prediction of disturbing, so the accuracy of CQI is generally all lower.

Under the situation of MU-MIMO,, also can when calculating, CQI consider the interference that the multi-user brings roughly though receiving terminal can not accurately be known following multi-user's interference.One of them method is the calculating that might all do a SINR to all with the precoding of oneself matching, does average then.For example in Release 8, the code book of 2 antennas is:

When each user's order is 1, the selection of 4 numerals is arranged.If transmitting terminal is allowed nonopiate pairing,, that is to say 3 different possibilities of disturbing just then each user has 3 numerals to match.Under this situation, can calculate each possibility and remake then on average:

${\mathrm{SINR}}_{\mathrm{MU}}=\frac{1}{S-1}\underset{w_k\∈{\mathrm{Cint}}_n}{\overset{S-1}{\mathrm{\Σ}}}{f}_1^{*}{({\hat{R}}_{\mathrm{nn}}+\left({\mathrm{Hw}}_k\right){\left({\mathrm{Hw}}_k\right)}^{*})}^{-1}{f}_1,$ Wherein ${\hat{R}}_{\mathrm{nn}}=\underset{i}{\overset{\mathrm{nu}\min t}{\mathrm{\Σ}}}{H}_i{H_i}^{*}+N_{o}I.$

Wherein S is the quantity of numeral, promptly equals 4; w _kIt is the precoding of disturbing.Can do a general estimation with disturbing like this, but this method is only to be used to have the situation of code book, if there is not code book, the precoding of interference can have a lot of possibilities, just that cannot do a prediction.

Summary of the invention

Technical problem to be solved by this invention is to provide the feedback method of channel quality in a kind of multi-input multi-output system, to be used for receiving terminal to transmitting terminal feedback channel quality information.

In order to solve the problems of the technologies described above, the invention provides the feedback method of channel quality in a kind of multi-input multi-output system, be used for described multi-input multi-output system receiving terminal to transmitting terminal feedback channel quality information, wherein, described receiving terminal estimates that according to the passing interference in a current time interval current interference to after the influence of channel quality and obtaining described channel quality information, feeds back described channel quality information to described transmitting terminal.

Preferably, described receiving terminal is estimated described channel quality according to described passing interference, comprise the mean value that calculates described passing interference and estimate described channel quality, perhaps estimate described channel quality by the multi-user interference in the described time interval is filtered according to described mean value.

Further, described estimation comprises according to public guide frequency and demodulation pilot frequency and carrying out.

Again further, for the bilayer transmission of single user's multi-input multi-output system, when the quantity of public guide frequency port is less than number of transmit antennas,

Described receiving terminal is estimated the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to described public guide frequency _TXD

Described receiving terminal is estimated the equivalent channel vector of the equivalent channel vector sum second layer of acquisition ground floor according to demodulation pilot frequency;

Described receiving terminal obtains ground floor according to the equivalent channel of described ground floor vector not to be had interlayer interference and the ground floor channel quality indicator difference Δ CQI of interlayer interference is being arranged ₁

Described receiving terminal obtains the second layer according to the equivalent channel of described second layer vector not to be had interlayer interference and the second layer channel quality indicator difference Δ CQI of interlayer interference is being arranged ₂

Described receiving terminal is according to described Δ CQI ₁With Δ CQI ₂Obtain CQI mean value Δ CQI;

Described receiving terminal is with described CQI _TXDAnd Δ CQI feeds back to described transmitting terminal;

Wherein:

Described ${\mathrm{\ΔCQI}}_1=Q({\hat{f}}_1^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_1-{\hat{f}}_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_1);$

Described ${\mathrm{\ΔCQI}}_2=Q({\hat{f}}_2^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_2-{\hat{f}}_2^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_2);$

Described Δ CQI=(Δ CQI ₁+ Δ CQI ₂)/2;

T is the described time interval, and t is a current time;

For estimate the equivalent channel vector of the described ground floor of acquisition according to described demodulation pilot frequency;

For estimate the equivalent channel vector of the described second layer of acquisition according to described demodulation pilot frequency;

${\hat{R}}_{\mathrm{nn}}=\underset{i}{\overset{\mathrm{nu}\min t}{\mathrm{\Σ}}}{H}_i{H_i}^{*}+N_{o}I;$

Num int represents the number of interfered cell;

H _iThe expression presence of intercell interference;

H _i ^*Expression H _iTransposed matrix;

N _oI represents the white noise of Gaussian Profile;

f _Int(k) interlayer interference that obtains according to described demodulation pilot frequency of expression;

Q (x) expression is carried out quantization operations to x.

And described receiving terminal is further to described transmitting terminal feedback order indication (RI).

Further, described receiving terminal estimates that according to described passing interference current interference to the influence of channel quality and obtain the step of described channel quality information, comprising:

For the bilayer transmission of single user's multi-input multi-output system, when the quantity of public guide frequency port is less than number of transmit antennas,

Described receiving terminal is estimated the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to described public guide frequency _TXD

Described receiving terminal is estimated the equivalent channel vector of the equivalent channel vector sum second layer of acquisition ground floor according to demodulation pilot frequency;

Described receiving terminal obtains ground floor according to the equivalent channel of described ground floor vector not to be had interlayer interference and the ground floor channel quality indicator difference Δ CQI of interlayer interference is being arranged ₁

Described receiving terminal obtains the second layer according to the equivalent channel of described second layer vector not to be had interlayer interference and the second layer channel quality indicator difference Δ CQI of interlayer interference is being arranged ₂

Described receiving terminal is according to described Δ CQI ₁With Δ CQI ₂Obtain CQI mean value Δ CQI;

Described receiving terminal is 1 to the described RI of described transmitting terminal feedback, and feeds back described CQI simultaneously _TXDPerhaps described receiving terminal is 2 to the described RI of described transmitting terminal feedback, and feeds back described CQI simultaneously _TXDDifference CQI with described Δ CQI _E

Wherein:

Described ${\mathrm{\ΔCQI}}_1=Q({\hat{f}}_1^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_1-{\hat{f}}_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_1);$

Described ${\mathrm{\ΔCQI}}_2=Q({\hat{f}}_2^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_2-{\hat{f}}_2^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_2);$

Described Δ CQI=(Δ CQI ₁+ Δ CQI ₂)/2;

Described CQI _E=CQI _TXD-Δ CQI;

T is the described time interval, and t is a current time;

For estimate the equivalent channel vector of the described ground floor of acquisition according to described demodulation pilot frequency;

For estimate the equivalent channel vector of the described second layer of acquisition according to described demodulation pilot frequency;

${\hat{R}}_{\mathrm{nn}}=\underset{i}{\overset{\mathrm{nu}\min t}{\mathrm{\Σ}}}{H}_i{H_i}^{*}+N_{o}I;$

Num int represents the number of interfered cell;

H _iThe expression presence of intercell interference;

H _i ^*Expression H _iTransposed matrix;

N _oI represents the white noise of Gaussian Profile;

f _Int(k) interlayer interference that obtains according to described demodulation pilot frequency of expression;

Q (x) expression is carried out quantization operations to x.

And described receiving terminal estimates that according to described passing interference current interference to the influence of channel quality and obtain the step of described channel quality information, comprising:

Described receiving terminal is estimated the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to described public guide frequency _TXD

Described receiving terminal estimates to obtain the equivalent channel vector of ground floor according to described demodulation pilot frequency;

Described receiving terminal obtains not have multi-user interference and the glitch-free channel quality indicator difference Δ of multi-user CQI according to the equivalent channel vector of described ground floor _SM

Described receiving terminal is 1 to the described RI of described transmitting terminal feedback, and feeds back described CQI simultaneously _TXDPerhaps described receiving terminal is 2 to the described RI of described transmitting terminal feedback, and feeds back CQI simultaneously _TXD-Δ CQI _SM

Wherein: ${\mathrm{\ΔCQI}}_{\mathrm{SM}}=Q({\hat{f}}_1^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_1-{\hat{f}}_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_1);$

T is the described time interval, and t is a current time;

For estimate to obtain the equivalent channel vector of ground floor according to described demodulation pilot frequency;

${\hat{R}}_{\mathrm{nn}}=\underset{i}{\overset{\mathrm{nu}\min t}{\mathrm{\Σ}}}{H}_i{H_i}^{*}+N_{o}I;$

Num int represents the number of interfered cell;

H _iThe expression presence of intercell interference;

H _i ^*Expression H _iTransposed matrix;

N _oI represents the white noise of Gaussian Profile;

f _Int(k) interlayer interference that obtains according to described demodulation pilot frequency of expression;

Q (x) expression is carried out quantization operations to x.

Compared with prior art, the feedback method of channel quality in the multi-input multi-output system that the present invention proposes, receiving terminal can obtain more accurately channel quality information and feed back to transmitting terminal when having multilayer to disturb, and receiving terminal is not having to obtain to estimate preferably effect under the code book situation yet.

Description of drawings

Fig. 1 is the schematic flow sheet of first mode in the first embodiment of the invention;

Fig. 2 is the schematic flow sheet of second mode in the first embodiment of the invention;

Fig. 3 is the schematic flow sheet of cubic formula in the second embodiment of the invention;

Fig. 4 is the schematic flow sheet of the 5th mode in the second embodiment of the invention;

Fig. 5 schematic flow sheet that to be transmitting terminal of the present invention transmit according to the channel quality information of receiving terminal feedback;

Fig. 6 is the schematic flow sheet of fourth embodiment of the invention;

Fig. 7 is the schematic flow sheet of fifth embodiment of the invention;

Fig. 8 is the schematic flow sheet of sixth embodiment of the invention.

Embodiment

Describe embodiments of the present invention in detail below with reference to drawings and Examples, how the application technology means solve technical problem to the present invention whereby, and the implementation procedure of reaching technique effect can fully understand and implements according to this.

Receiving terminal is when calculating and feed back CQI or SINR among the present invention, estimate the influence of current interference according to passing interference to CQI or SINR, such as averaging by the end of working as the interference of previous T in the time interval, estimate current channel quality information according to this mean value to passing.After obtaining channel quality information, give transmitting terminal with the channel quality information feedback obtained, transmitting terminal carries out transmission with receiving terminal according to this channel quality information.

Estimate current interference according to passing interference, wherein a kind of method is to measure estimation by pilot tone.Comprise a kind of demodulation pilot frequency (Demodulation Reference Signal in the standard of LTE, DMRS), be the dedicated pilot of transmitting terminal (eNB) to each receiving terminal (UE) emission, this pilot tone need be passed through precoding processing when emission, the same with data precoding.Therefore be positioned at which layer as long as UE knows the channel of oneself, just can learn that other layer all is to disturb, can realize Interference Estimation from the DMRS of interfere with layer.

Below be divided into MU-MIMO and SU-MIMO the computational methods of estimating CQI by DMRS are described respectively.

For the MU-MIMO situation

Under the situation of MU-MIMO, if total M user, then the CQI of user m ' and SINR are respectively:

${\mathrm{SINR}}_{\mathrm{MU},m\′}=f_{m\′}^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}\underset{m=1,m\≠m\′}{\overset{M}{\mathrm{\Σ}}}{f}_{\mathrm{int},m}\left(k\right)f_{\mathrm{int},m}{\left(k\right)}^{*})}^{-1}{f}_{m\′}$ Formula (5)

CQI _{MU, m '}=Q (SINR _{MU, m '}) formula (6)

Wherein, t represents the current time, and the T express time at interval;

f _int，m(t)＝H _int，m(t)w _int，m(t)；

Wherein, $\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}\underset{m=1,m\≠m\′}{\overset{M}{\mathrm{\Σ}}}{f}_{\mathrm{int},m}\left(k\right)f_{\mathrm{int},m}{\left(k\right)}^{*}$ The mean value of multi-user interference in the expression T time interval.

Q (x) expression in the formula (6) is carried out quantization operations to x.

F wherein _{Int, m}(t)=H _{Int, m}(t) w _{Int, m}(t) be through the multi-user interference after the precoding processing, can obtain according to DMRS.Current time is averaged processing to the interference of this section in the time before the T time period, perhaps can filter current time T time period multi-user interference before with filter.Certainly, T also can equal 1, does not promptly do on average, only does Interference Estimation according to current DMRS, and both T equaled 1 up-to-date style (5) and is expressed as:

${\mathrm{SINR}}_{\mathrm{MU},m\′}=f_{m\′}^{*}{({\hat{R}}_{\mathrm{nn}}+\underset{m=1,m\≠m\′}{\overset{M}{\mathrm{\Σ}}}{f}_{\mathrm{int},m}\left(t\right)f_{\mathrm{int},m}{\left(t\right)}^{*})}^{-1}{f}_{m\′}$ Formula (5-1)

Need to prove, carry out interference filter by filter, and T equal 1 the expression do not do average treatment, be equally applicable to the SU-MIMO situation.

Under multi-user's scene, disturbing mainly is the co-channel interference that produces with other users of sub-district, and these disturb all is through precoding processing, so the size of disturbing all depends on eNB with changing.For different e NB, adopt different pairing and precoding processing, thereby produce different interference.By statistics, can know that eNB produces the probable strength that disturbs, thereby an estimation is done in the influence of CQI disturbing before.

For the SU-MIMO situation

Under the situation of SU-MIMO, if double-deck transmission, the CQI of ground floor and the calculating of SINR can be write as:

${\mathrm{SINR}}_{\mathrm{SU},1}=f_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{f}_1$ Formula (7)

CQI _{SU, 1}=Q (SINR _{SU, 1}) formula (8)

F wherein _Int(t)=H (t) w ₂(t).

Wherein, $\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*}$ The mean value of multi-user interference in the expression T time interval.

Wherein, H (t) w ₂(t) be by the interlayer interference after the precoding processing, can obtain from DMRS.The same with multi-user's scene, current time is averaged processing to the interference of this section in the time before the T time period, perhaps can filter current time T time period multilayer before and disturb with filter.

For the second layer, computational methods are the same with ground floor, that is:

The Signal to Interference plus Noise Ratio SINR of the second layer in the double-deck transmission _{SU, 2}And channel quality indicator CQI _{SU, 2}Be respectively:

${\mathrm{SINR}}_{\mathrm{SU},2}=f_2^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{f}_2$ Formula (7-1)

CQI _{SU, 2}=Q (SINR _{SU, 2}) formula (8-1)

Wherein:

f _iEquivalent channel vector for layer i;

${\hat{R}}_{\mathrm{nn}}=\underset{i}{\overset{\mathrm{nu}\min t}{\mathrm{\Σ}}}{H}_i{H_i}^{*}+N_{o}I;$

Num int represents the number of interfered cell;

H _iThe expression presence of intercell interference;

H _i ^*Expression H _iTransposed matrix;

N _oI represents the white noise of Gaussian Profile;

Q (x) expression is carried out quantization operations to x;

F wherein _Int(t)=H (t) w ₁(t), H (t) w ₁(t) be by the interlayer interference after the precoding processing, can obtain from DMRS.

Wherein, $\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*}$ The mean value of multi-user interference in the expression T time interval.

Certainly, T also can equal 1, does not promptly do on average, only does Interference Estimation according to current DMRS, and both T equaled 1 up-to-date style (7) and is expressed as:

${\mathrm{SINR}}_{\mathrm{SU},1}=f_1^{*}{({\hat{R}}_{\mathrm{nn}}+f_{\mathrm{int}}\left(t\right)f_{\mathrm{int}}{\left(t\right)}^{*})}^{-1}{f}_1$ Formula (7-2)

Formula (7-1) is expressed as:

${\mathrm{SINR}}_{\mathrm{SU},2}=f_2^{*}{({\hat{R}}_{\mathrm{nn}}+f_{\mathrm{int}}\left(t\right)f_{\mathrm{int}}{\left(t\right)}^{*})}^{-1}{f}_2$ Formula (7-3)

Utilize embodiment how explanation is come the calculating channel quality by demodulation pilot frequency below.

First embodiment

In LTE Release 8,, belong to a kind of single current wave beam forming (Beamforming, BF) The Application of Technology based on the transmission of single antenna port 5.In order to strengthen the performance of descending non-code book transmission means, in the enhancing version Release 9 of LTE, a kind of new transmission means has been proposed, belong to a kind of order and be 2 non-code book spatial multiplexing mode, just adopted the transmission of two antenna ports of double-current BF technology.

Under single user's double fluid BF scene, because be not based on the mode of code book, eNB can oneself determine the method for precoding processing.Though eNB generally makes two-layer precoding vector orthogonalization, because the various errors of real system, when signal arrived UE, the interference of interlayer was difficult to avoid, and can carry out the calculating of CQI with the average method of interference in this case:

The CQI of ground floor is:

${\mathrm{SINR}}_{\mathrm{SU},1}=f_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{f}_1$ Formula (9)

CQI _{SU, 1}=Q (SINR _{SU, 1}) formula (10)

F wherein _Int(t)=H (t) w ₂(t).

The CQI of the second layer is:

${\mathrm{SINR}}_{\mathrm{SU},2}=f_2^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{f}_2$ Formula (11)

CQI _{SU, 2}=Q (SINR _{SU, 2}) formula (12)

F wherein _Int(t)=H (t) w ₁(t).

When receiving terminal feedback SINR or CQI (CQI is that example describes with feedback), include following first, second and third totally three kinds of modes:

First mode

UE directly feeds back two CQI, i.e. CQI _{SU, 1}And CQI _{SU, 2}

Fig. 1 is when the quantity of public guide frequency CRS (Common Reference Signal) port (port) is no less than number of transmit antennas, and receiving terminal feedback channel quality information is given the schematic flow sheet of first mode of transmitting terminal in the SU-MIMO system.As shown in Figure 1, this flow process mainly comprises the steps:

Step S110, UE estimates channel matrix H according to public guide frequency CRS (Common Reference Signal);

Step S120, UE obtains two characteristic vectors according to this channel matrix H;

Step S130, UE obtain the equivalent channel vector f of ground floor according to these two characteristic vectors ₁Equivalent channel vector f with the second layer ₂

Step S140, UE calculate the mean value of interlayer interference according to DMRS;

Step S150, UE is according to this mean value and this f ₁And f ₂, obtain the ground floor channel quality indicator CQI _{SU, 1}With second layer channel quality indicator CQI _{SU, 2}

Step S160, UE is with this CQI _{SU, 1}And CQI _{SU, 2}Feed back to transmitting terminal.

Second mode

Above-mentioned first mode is based on the channel that UE can be known all antennas, this needs the quantity of CRS port to be no less than number of transmit antennas, for example the quantity of maximum CRS is 4 in Release 8, if transmitting terminal has 8 antennas, this moment, above-mentioned first mode was then inapplicable.

When the quantity of CRS port (port) was less than number of transmit antennas, (used CQI here to feed back CQI with the transmit diversity form of the transmission that is similar to Release 8 ports 5 _TXDRepresent), based on average interlayer interference CQI is turned down then, obtain the equivalent channel vector f of ground floor according to DMRS ₁Equivalent channel vector f with the second layer ₂, use respectively at this

With

The equivalent channel vector f of the ground floor that expression estimates according to DMRS ₁Equivalent channel vector f with the second layer ₂So the SINR of ground floor when interlayer interference is arranged is:

${\mathrm{SINR}}_{\mathrm{SU},1}={\hat{f}}_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_1$ Formula (13)

Ground floor is not having interlayer interference and is having the ground floor CQI difference of interlayer interference to be:

${\mathrm{\ΔCQI}}_1=Q({\hat{f}}_1^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_1-{\hat{f}}_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_1)$ Formula (14)

Use the process the same, can obtain the second layer CQI difference of the second layer when not having interlayer interference and interlayer interference is arranged and be with ground floor:

${\mathrm{\ΔCQI}}_2=Q({\hat{f}}_2^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_2-{\hat{f}}_2^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_2)$ Formula (15)

Calculate the CQI mean value of ground floor CQI difference and second layer CQI difference:

Δ CQI=(Δ CQI ₁+ Δ CQI ₂)/2 formulas (16)

According to CQI _TXDAnd this CQI mean value obtains the CQI estimated value:

CQI _E=CQI _TXD-Δ CQI formula (17)

Receiving terminal is with this CQI estimated value CQI _EFeed back to transmitting terminal, so just can all be reflected in CQI to the interlayer interference that estimates _EIn the computational process.Transmitting terminal eNB receives CQI _EAfter estimate that according to eNB oneself two characteristic vectors of channel do the adjustment of CQI between the different layers again.Fig. 2 is the schematic flow sheet of above-mentioned second mode of the present invention.As shown in Figure 2, this flow process mainly comprises the steps:

Step S210, UE estimate the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to public guide frequency CRS _TXD

Step S220, UE estimate the equivalent channel vector of ground floor according to DMRS

Equivalent channel vector with the second layer

Step S230, UE is according to being somebody's turn to do

Calculating ground floor is not having interlayer interference and the ground floor CQI difference DELTA CQI of interlayer interference is being arranged ₁

Step S240, UE is according to being somebody's turn to do

Calculating the second layer is not having interlayer interference and the second layer CQI difference DELTA CQI of interlayer interference is being arranged ₂

Step S250 is according to this ground floor CQI difference DELTA CQI ₁With second layer CQI difference DELTA CQI ₂Obtain CQI mean value Δ CQI=(Δ CQI ₁+ Δ CQI ₂)/2;

Step S260, UE is according to this CQI _TXDAnd CQI mean value Δ CQI obtains CQI estimated value CQI _E=CQI _TXD-Δ CQI feeds back to transmitting terminal.

Third Way

Compare with aforesaid second mode, Third Way is after obtaining ground floor CQI difference and second layer CQI difference, according to ground floor CQI difference and second layer CQI difference, and CQI _TXDObtain:

Ground floor CQI estimated value is:

CQI _1E=CQI _TXD-Δ CQI ₁Formula (18)

Second layer CQI estimated value is:

CQI _2E=CQI _TXD-Δ CQI ₂Formula (19)

Receiving terminal is with this ground floor CQI estimated value CQI _1EAnd second layer CQI estimated value CQI _2EFeed back to transmitting terminal.

Second embodiment

Double fluid BF also can support multiuser MIMO, and each user only accounts for a stream (order is 1).It is 2 that first embodiment requires the order of single subscriber channel, if the order of channel is 1, then needs multiuser MIMO to do spatial reuse.If the order of channel is 1 not have the user to do pairing again, then need to adopt single user's single current BF.In this single current BF pattern, support the switching of dynamic single user's single current BF and multi-user BF, present embodiment adopts the feedback method of differential CQI.

At first calculate the CQI of single current BF:

${\mathrm{CQI}}_{\mathrm{SU},1}=Q\left({\mathrm{SINR}}_{\mathrm{SU},1}\right)=Q\left(f_1^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{f}_1\right)$ Formula (20)

And then the difference DELTA CQI between calculating single current BF and the double-current BF _SD:

${\mathrm{\ΔCQI}}_{\mathrm{SD}}={\mathrm{CQI}}_{\mathrm{SU},1}-Q\left({\mathrm{SINR}}_{\mathrm{MU}}\right)$

$={\mathrm{CQI}}_{\mathrm{SU},1}-Q\left(f_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{f}_1\right)$ Formula (21)

Receiving terminal is with this Δ CQI _SDAfter feeding back to transmitting terminal eNB, if eNB finds two users to do pairing, can be from CQI _{SU, 1}With Δ CQI _SDCalculate multi-user's CQI _MU=CQI _{SU, 1}-Δ CQI _SDIf do not have the user to do pairing and just use CQI _{SU, 1}Do single user's transmission.

When receiving terminal feedback SINR or CQI (CQI is that example describes with feedback), include the following the 4th and the 5th and be total to dual mode:

Cubic formula

The manner is to utilize the mode of difference to feed back CQI, supports dynamic single user and multi-user's switching, for example under order is 1 situation, because have only one deck, does not have the interference of multilayer, and the glitch-free CQI of single user is:

${\mathrm{CQI}}_{\mathrm{SU},1}=Q\left({\mathrm{SINR}}_{\mathrm{SU},1}\right)=Q\left(f_1^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{f}_1\right)$ Formula (22)

The difference of itself and multi-user CQI is:

${\mathrm{\ΔCQI}}_{\mathrm{SM}}={\mathrm{CQI}}_{\mathrm{SU},1}-Q\left({\mathrm{SINR}}_{\mathrm{MU}}\right)$

$={\mathrm{CQI}}_{\mathrm{SU},1}-Q\left(f_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{f}_1\right)$ Formula (23)

Because multi-user's CQI is the CQI that is lower than single user, so Δ CQI _SMBe positive number, quantizing Δ CQI _SMIn time, can feed back with the bit more a little less than CQI, for example CQI _{SU, 1}Be to quantize, can quantize with 3 bits with 5 bits.

Fig. 3 is the schematic flow sheet of the above-mentioned cubic formula of the present invention.As shown in Figure 3, this flow process mainly comprises the steps:

Step S310, UE estimates channel matrix H according to public guide frequency CRS;

Step S320, UE obtains a characteristic vector the strongest according to this channel matrix H;

Step S330, UE obtain the equivalent channel vector f of ground floor according to this strongest characteristic vector ₁

Step S340, UE calculate the mean value of multi-user interference according to DMRS $\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*};$

Step S350, UE is according to this f ₁, obtain single user's clear channel quality indicator CQI _{SU, 1}

Step S360, UE is according to this mean value and this f ₁, obtain this list user clear channel quality indicator CQI _{SU, 1}Difference DELTA CQI with multi-user CQI _SM

Step S370, UE is with this CQI _{SU, 1}With Δ CQI _SMFeed back to transmitting terminal.

The 5th mode

The manner is to obtain the equivalent channel vector f of ground floor from CRS at UE ₁Situation under (quantity such as CRS port is no less than number of transmit antennas), can estimate to obtain the equivalent channel vector f of ground floor according to DMRS ₁, in this usefulness

Represent the amount that estimates according to DMRS, thus with the noiseless CQI of single user _{SU, 1}Difference be:

${\mathrm{\ΔCQI}}_{\mathrm{SM}}=Q({\hat{f}}_1^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_1-{\hat{f}}_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_1)$ Formula (24)

In this case, receiving terminal is to the CQI of transmitting terminal feedback with the transmit diversity form of the transmission of Release 8 ports 5 _TXDAnd this Δ CQI _SM

Fig. 4 is the schematic flow sheet of above-mentioned the 5th mode of the present invention.As shown in Figure 4, this flow process mainly comprises the steps:

Step S410, UE estimate the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to public guide frequency CRS _TXD

Step S420, UE estimate the equivalent channel vector of ground floor according to DMRS

Step S430, UE is according to the equivalent channel vector of this ground floor

Calculating is not having multi-user interference and the CQI difference DELTA CQI that multi-user interference is arranged _SM

Step S440, UE is with this CQI _TXDAnd this Δ CQI _SMFeed back to transmitting terminal.

Need to prove that above-mentioned first embodiment and second embodiment can use with, it is 2 o'clock that Fig. 2 is the highest order of channel, the schematic flow sheet that the channel quality information that transmitting terminal feeds back according to receiving terminal transmits.As shown in Figure 5, when first embodiment and second embodiment used with, the channel quality that transmitting terminal feeds back according to receiving terminal transmitted mainly and comprises the steps:

Step S510, the order of receiving terminal UE calculating channel;

Step S520 judges whether the order of this channel is 1, and being changes step S530 for 1, otherwise changes step S550;

Step S530, UE calculate single user's clear channel quality indicator CQI _{SU, 1}

Step S540, UE calculate this list user clear channel quality indicator CQI _{SU, 1}With the difference DELTA CQI of multiuser channel quality indicator, and should list user clear channel quality indicator CQI _{SU, 1}And this difference DELTA CQI feeds back to transmitting terminal eNB, commentaries on classics step S560;

Step S550, UE calculates double-deck channel quality, obtains the ground floor channel quality indicator CQI _{SU, 1}And second layer channel quality indicator CQI _{SU, 2}, and with this ground floor channel quality indicator CQI _{SU, 1}And second layer channel quality indicator CQI _{SU, 2}Feed back to transmitting terminal, change step S590;

Step S560, transmitting terminal attempt carrying out multi-user's pairing, and judge whether success of pairing, and be successful then change step S570, otherwise commentaries on classics step S580;

Step S570, transmitting terminal adopt multi-user's double fluid BF to carry out message transmission;

Step S580, transmitting terminal adopt single user's single current BF to carry out message transmission;

Step S590, transmitting terminal adopt single user's double fluid BF to carry out message transmission.

The 3rd embodiment

The pattern 5 of the Release 8 of LTE is supported the transmission based on the multiuser MIMO of code book.In Release 10 versions that strengthen Long Term Evolution (LTE-Advanced), UE also can be based on code book in feedback CQI and PMI, but in order to strengthen the performance of MU-MIMO, still can support the transmission of non-code book multiuser MIMO in the time of the eNB transmission.Under this pattern, because also be to use DMRS to come demodulation, so the execution mode of multi-user's double fluid BF also can adopt DMRS to estimate to disturb equally.With multi-user's double fluid BF difference, mainly be can be multiplexing more than two users.Below be exactly under M user's situation, the CQI computational methods of user m ':

${\mathrm{SINR}}_{\mathrm{MU},m\′}=f_{m\′}^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}\underset{m=1,m\≠m\′}{\overset{M}{\mathrm{\Σ}}}{f}_{\mathrm{int},m}\left(k\right)f_{\mathrm{int},m}{\left(k\right)}^{*})}^{-1}{f}_{m\′}$ Formula (25)

CQI _{MU, m '}=Q (SINR _{MU, m '}) formula (26)

F wherein _{Int, m}(t)=H _{Int, m}(t) w _{Int, m}(t).

H wherein _{Int, m}(t) w _{Int, m}(t) be by the interference after the precoding processing, can obtain according to DMRS from user m generation.All users' interference is added up, and reoperate time is average (in (25) then

Shown in be the average treatment of time), obtain channel quality information as the formula (26).Time on average be by now with the estimation of the interference between before the T calculate one average, the multi-user interference before perhaps can filtering with filter.

Certainly, time interval T is 1 o'clock, and formula (25) is:

${\mathrm{SINR}}_{\mathrm{MU},m\′}=f_{m\′}^{*}{({\hat{R}}_{\mathrm{nn}}+\underset{m=1,m\≠m\′}{\overset{M}{\mathrm{\Σ}}}{f}_{\mathrm{int},m}\left(k\right)f_{\mathrm{int},m}{\left(k\right)}^{*})}^{-1}{f}_{m\′}$ Formula (25-1)

F wherein _{M '}=Hw _M/Be equivalent channel vector by the user m ' after the precoding processing, precoding w _M/Be based on that code book selects.

The 4th embodiment

Under the scene of single user BF, another kind of feedback system is the feedback model of reusing mode 3 among the LTE Release 8, and form original in the mode 3 is made adjustment.

In mode 3, the UE feedback data is that RI and CQI are arranged, when RI is 1, the suggestion transmission mode of UE is transmit diversity (Transmit diversity), when RI is 2, the suggestion transmission mode of UE is Open-Loop Spatial Multiplexing (Open loop spatial multiplexing), and UE is CQI of feedback at any RI.

Under single user's double fluid BF scene, if support the switching of dynamic single current BF and double-current BF, eNB preferably has CQI _TXDAnd CQI _E, CQI wherein _E=CQI _TXD-Δ CQI calculates acquisition with second mode of aforementioned first embodiment.By the form of re-use pattern therefor 3, UE is at different time feedback CQI _TXDOr CQI _E, then with RI notify eNB this be CQI _TXDPerhaps CQI _EIn the time of RI=1, that UE feeds back is CQI _TXDIn the time of RI=2, that UE feeds back is exactly CQI _EENB just can have single current BF two CQIs relative with double-current BF like this, eNB can do rank adaptation (rank adaptation) processing together according to these two CQI and eNB estimated channel characteristic value then, and then selects the transmission mode of single current BF or double-current BF.

Fig. 6 is the schematic flow sheet of fourth embodiment of the invention.As shown in Figure 6, fourth embodiment of the invention mainly comprises the steps:

Step S610, UE estimate the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to public guide frequency CRS _TXD

Step S620, UE estimate the equivalent channel vector of ground floor according to DMRS

Equivalent channel vector with the second layer

Step S630, UE is according to being somebody's turn to do Calculating ground floor is not having interlayer interference and the ground floor CQI difference DELTA CQI of interlayer interference is being arranged ₁

Step S640, UE is according to being somebody's turn to do

Calculating the second layer is not having interlayer interference and the second layer CQI difference DELTA CQI of interlayer interference is being arranged ₂

Step S650 is according to this ground floor CQI difference DELTA CQI ₁With second layer CQI difference DELTA CQI ₂Obtain CQI mean value Δ CQI=(Δ CQI ₁+ Δ CQI ₂)/2;

Step S660, UE is according to this CQI _TXDFeed back to transmitting terminal, also feed back this CQI of RI=1 notice eNB simultaneously _TXDBe the CQI of single current BF;

Step S670, at another one time (for example next feedback cycle), UE is according to this CQI _TXDAnd CQI mean value Δ CQI obtains CQI estimated value CQI _E=CQI _TXD-Δ CQI is with this CQI _EFeed back to transmitting terminal, also feed back RI=2 simultaneously, this CQI of notice eNB _EBe the CQI of double-current BF;

Step S680, eNB is according to the own estimated channel data of eNB (for example channel characteristic value), and CQI _TXDPerhaps CQI _EThe sum of ranks Modulation and Coding Scheme of selection actual transmissions (Modulation CodingScheme, MCS).

The 5th embodiment

Feedback system in the present embodiment adopts new feedback model, and UE feeds back CQI simultaneously _TXDWith Δ CQI.Fig. 7 is the schematic flow sheet of fifth embodiment of the invention.As shown in Figure 7, fifth embodiment of the invention mainly comprises the steps:

Step S710, UE estimate the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to public guide frequency CRS _TXD

Step S720, UE estimate the equivalent channel vector of ground floor according to DMRS

Equivalent channel vector with the second layer

Step S730, UE is according to being somebody's turn to do

Calculating ground floor is not having interlayer interference and the ground floor CQI difference DELTA CQI of interlayer interference is being arranged ₁

Step S740, UE is according to being somebody's turn to do

Calculating the second layer is not having interlayer interference and the second layer CQI difference DELTA CQI of interlayer interference is being arranged ₂

Step S750 is according to this ground floor CQI difference DELTA CQI ₁With second layer CQI difference DELTA CQI ₂Obtain CQI mean value Δ CQI=(Δ CQI ₁+ Δ CQI ₂)/2;

Step S760, UE is with this CQI _TXDCQI feeds back to eNB with Δ;

Step S770, eNB can be according to CQI _TXD, Δ CQI and the own estimated channel data of eNB (for example channel characteristic value) select the sum of ranks MCS of actual transmissions.

The 6th embodiment

Aforementioned the 4th embodiment also can be used in multi-user's scene, reuses the feedback model of mode 3 among the LTE Release 8 equally.In the time of RI=1, that UE feeds back is exactly CQI _TXDIn the time of RI=2, that UE feeds back is exactly CQI _TXD-Δ CQI _SM, Δ CQI _SMRepresenting multi-user interference to the influence that CQI brings, is the same account form acquisition with second embodiment the 5th mode.

Fig. 8 is the schematic flow sheet of the inventive method the 6th embodiment.As shown in Figure 8, sixth embodiment of the invention mainly comprises the steps:

Step S810, UE estimate the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to public guide frequency CRS _TXD

Step S820, UE estimate the equivalent channel vector of ground floor according to DMRS

Step S830, UE is according to the equivalent channel vector of this ground floor

Calculating is not having multi-user interference and the CQI difference DELTA CQI that multi-user interference is arranged _SM

Step S840, UE is with this CQI _TXDFeed back to transmitting terminal, also feed back RI=1 simultaneously, this CQI of notice eNB _TXDBe the CQI of single user's single current BF;

Step S850, at another one time (for example next feedback cycle), UE is with this CQI _TXD-Δ CQI _SMFeed back to transmitting terminal, also feed back RI=2 simultaneously, this CQI of notice eNB _TXD-Δ CQI _SMBe multi-user's CQI;

Step S860, eNB can be according to own estimated channel data (for example channel characteristic value), and CQI _TXDPerhaps CQI _TXD-Δ CQI _SMSelect the sum of ranks MCS of actual transmissions.

Though the disclosed execution mode of the present invention as above, the execution mode that described content just adopts for the ease of understanding the present invention is not in order to limit the present invention.Technical staff in any the technical field of the invention; under the prerequisite that does not break away from the disclosed spirit and scope of the present invention; can do any modification and variation what implement in form and on the details; but scope of patent protection of the present invention still must be as the criterion with the scope that appending claims was defined.

Claims (7)

1, the feedback method of channel quality in a kind of multi-input multi-output system, be used for described multi-input multi-output system receiving terminal to transmitting terminal feedback channel quality information, it is characterized in that, described receiving terminal estimates that according to the passing interference in a current time interval current interference to after the influence of channel quality and obtaining described channel quality information, feeds back described channel quality information to described transmitting terminal.

2, the method for claim 1 is characterized in that:

Described receiving terminal is estimated described channel quality according to described passing interference, comprise the mean value that calculates described passing interference and estimate described channel quality, perhaps estimate described channel quality by the multi-user interference in the described time interval is filtered according to described mean value.

3, method as claimed in claim 2 is characterized in that:

Described estimation comprises according to public guide frequency and demodulation pilot frequency and carrying out.

4, method as claimed in claim 3 is characterized in that:

For the bilayer transmission of single user's multi-input multi-output system, when the quantity of public guide frequency port is less than number of transmit antennas,

Described receiving terminal is estimated the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to described public guide frequency _TXD

Described receiving terminal is estimated the equivalent channel vector of the equivalent channel vector sum second layer of acquisition ground floor according to demodulation pilot frequency;

Described receiving terminal obtains ground floor according to the equivalent channel of described ground floor vector not to be had interlayer interference and the ground floor channel quality indicator difference Δ CQI of interlayer interference is being arranged ₁

Described receiving terminal obtains the second layer according to the equivalent channel of described second layer vector not to be had interlayer interference and the second layer channel quality indicator difference Δ CQI of interlayer interference is being arranged ₂

Described receiving terminal is according to described Δ CQI ₁With Δ CQI ₂Obtain CQI mean value Δ CQI;

Described receiving terminal is with described CQI _TXDAnd Δ CQI feeds back to described transmitting terminal;

Wherein:

Described ${\mathrm{\ΔCQI}}_1=Q({\hat{f}}_1^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_1-{\hat{f}}_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_1);$

Described ${\mathrm{\ΔCQI}}_2=Q({\hat{f}}_2^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_2-{\hat{f}}_2^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_2);$

Described Δ CQI=(Δ CQI ₁+ Δ CQI ₂)/2;

T is the described time interval, and t is a current time;

For estimate the equivalent channel vector of the described ground floor of acquisition according to described demodulation pilot frequency;

For estimate the equivalent channel vector of the described second layer of acquisition according to described demodulation pilot frequency;

${\hat{R}}_{\mathrm{nn}}=\underset{i}{\overset{\mathrm{nu}\min t}{\mathrm{\Σ}}}{H}_i{H_i}^{*}+N_{o}I;$

Num int represents the number of interfered cell;

H _iThe expression presence of intercell interference;

H _i ^*Expression H _iTransposed matrix;

N _oI represents the white noise of Gaussian Profile;

f _Int(k) interlayer interference that obtains according to described demodulation pilot frequency of expression;

Q (x) expression is carried out quantization operations to x.

5, method as claimed in claim 3 is characterized in that:

Described receiving terminal is further to described transmitting terminal feedback order indication (RI).

6, method as claimed in claim 5 is characterized in that, described receiving terminal estimates that according to described passing interference current interference to the influence of channel quality and obtain the step of described channel quality information, comprising:

For the bilayer transmission of single user's multi-input multi-output system, when the quantity of public guide frequency port is less than number of transmit antennas,

Described receiving terminal is estimated the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to described public guide frequency _TXD

Described receiving terminal is estimated the equivalent channel vector of the equivalent channel vector sum second layer of acquisition ground floor according to demodulation pilot frequency;

Described receiving terminal obtains ground floor according to the equivalent channel of described ground floor vector not to be had interlayer interference and the ground floor channel quality indicator difference Δ CQI of interlayer interference is being arranged ₁

Described receiving terminal obtains the second layer according to the equivalent channel of described second layer vector not to be had interlayer interference and the second layer channel quality indicator difference Δ CQI of interlayer interference is being arranged ₂

Described receiving terminal is according to described Δ CQI ₁With Δ CQI ₂Obtain CQI mean value Δ CQI;

Described receiving terminal is 1 to the described RI of described transmitting terminal feedback, and feeds back described CQI simultaneously _TXDPerhaps described receiving terminal is 2 to the described RI of described transmitting terminal feedback, and feeds back described CQI simultaneously _TXDDifference CQI with described Δ CQI _E

Wherein:

Described ${\mathrm{\ΔCQI}}_1=Q({\hat{f}}_1^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_1-{\hat{f}}_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_1);$

Described ${\mathrm{\ΔCQI}}_2=Q({\hat{f}}_2^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_2-{\hat{f}}_2^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_2);$

Described Δ CQI=(Δ CQI ₁+ Δ CQI ₂)/2;

Described CQ _IE=CQI _TXD-Δ CQI;

T is the described time interval, and t is a current time;

For estimate the equivalent channel vector of the described ground floor of acquisition according to described demodulation pilot frequency;

For estimate the equivalent channel vector of the described second layer of acquisition according to described demodulation pilot frequency;

${\hat{R}}_{\mathrm{nn}}=\underset{i}{\overset{\mathrm{nu}\min t}{\mathrm{\Σ}}}{H}_i{H_i}^{*}+N_{o}I;$

Num int represents the number of interfered cell;

H _iThe expression presence of intercell interference;

H _i ^*Expression H _iTransposed matrix;

N _oI represents the white noise of Gaussian Profile;

f _Int(k) interlayer interference that obtains according to described demodulation pilot frequency of expression;

Q (x) expression is carried out quantization operations to x.

7, method as claimed in claim 5 is characterized in that, described receiving terminal estimates that according to described passing interference current interference to the influence of channel quality and obtain the step of described channel quality information, comprising:

Described receiving terminal is estimated the channel quality indicator CQI of the transmit diversity form of Release 8 ports 5 according to described public guide frequency _TXD

Described receiving terminal estimates to obtain the equivalent channel vector of ground floor according to described demodulation pilot frequency;

Described receiving terminal obtains not have multi-user interference and the glitch-free channel quality indicator difference Δ of multi-user CQI according to the equivalent channel vector of described ground floor _SM

Described receiving terminal is 1 to the described RI of described transmitting terminal feedback, and feeds back described CQI simultaneously _TXDPerhaps described receiving terminal is 2 to the described RI of described transmitting terminal feedback, and feeds back CQI simultaneously _TXD-Δ CQI _SM

Wherein: ${\mathrm{\ΔCQI}}_{\mathrm{SM}}=Q({\hat{f}}_1^{*}{\hat{R}}_{\mathrm{nn}}^{-1}{\hat{f}}_1-{\hat{f}}_1^{*}{({\hat{R}}_{\mathrm{nn}}+\frac{1}{T}\underset{k=t-(T-1)}{\overset{t}{\mathrm{\Σ}}}{f}_{\mathrm{int}}\left(k\right)f_{\mathrm{int}}{\left(k\right)}^{*})}^{-1}{\hat{f}}_1);$

T is the described time interval, and t is a current time;

For estimate to obtain the equivalent channel vector of ground floor according to described demodulation pilot frequency;

${\hat{R}}_{\mathrm{nn}}=\underset{i}{\overset{\mathrm{nu}\min t}{\mathrm{\Σ}}}{H}_i{H_i}^{*}+N_{o}I;$

Num int represents the number of interfered cell;

H _iThe expression presence of intercell interference;

H _i ^*Expression H _iTransposed matrix;

N _oI represents the white noise of Gaussian Profile;

f _Int(k) interlayer interference that obtains according to described demodulation pilot frequency of expression;

Q (x) expression is carried out quantization operations to x.

Images