CN101877684B - Method and device for determining precoding matrix - Google Patents

Abstract

The invention discloses a method and a device for determining a precoding matrix. The method comprises the following steps of: determining a first channel response matrix of the current measurement period; determining a second channel response matrix of the last measurement period; estimating an inter-cell channel phase difference according to the first channel response matrix and the second channel response matrix; compensating the inter-cell channel phase difference to the second channel response matrix to obtain a third channel response matrix; and selecting the precoding matrix according to the third channel response matrix under the precoding algorithm rule. The method and the device can solve the problem of non-relevance caused by the change of the user position due to feedback time delay in the prior art, and can improve the performance of precoding jointly by a plurality of cells.

Description

A kind of definite method and device of pre-coding matrix

Technical field

The present invention relates to wireless communication technology, particularly a kind of definite method and device of pre-coding matrix.

Background technology

International Telecommunication Union is next generation mobile communication system IMT-Advanced (International Mobile Telecommunications-Advanced; International mobile telecommunication optimization) performance has proposed very high requirement: the maximum system transmission bandwidth reaches 100MHz; The peak rate of up-downgoing transfer of data will reach 500Mbps and 1Gbps respectively, and system's average spectral efficiency (ase) especially edge spectrum efficiency has been proposed very concrete demand.In order to satisfy the requirement of the new system of IMT-Advanced; 3GPP (3rd Generation partnership project; 3 generation collaborative project) (LTE is the abbreviation of Long Term Evolution at its mobile cellular communication LTE-Advanced of system of future generation; Be the evolution system of 3-G (Generation Three mobile communication system), the LTE-Advanced system is the upgrading of LTE system) in proposed to adopt the multi-point cooperative transmission technology to improve the performance of system.

COMP (Coordinated multi-point transmission/reception, cooperative multipoint transmission and reception) is the cooperation between a plurality of transmission points that separate on the geographical position, and in general, a plurality of transmission points are different sub-districts.The multi-point cooperative transmission technical scheme mainly is divided into two types: combined dispatching with unite transmission.Combined dispatching is the coordination through the time between the sub-district, frequency and space resources, for the resource that different UE (User Equipment, subscriber equipment) distributes mutually orthogonal, avoids interference each other.The interference of minizone is the principal element of restriction cell edge UE performance, so combined dispatching just can improve the performance of cell edge UE through the interference that reduces the minizone.Fig. 1 is the combined dispatching sketch map; As shown in Figure 1; Through the combined dispatching of 3 sub-districts, three UE that may the phase mutual interference have dispatched on the mutually orthogonal resource and (have represented different resources with different line styles among the figure), have effectively avoided the interference between the sub-district.

The difference of associating delivery plan and combined dispatching scheme is can send data to UE simultaneously by a plurality of sub-districts, to strengthen UE reception signal.Fig. 2 as shown in the figure, has only a sub-district different to UE transmission data with the combined dispatching scheme for uniting the transmission sketch map, has a plurality of sub-districts to send data to UE simultaneously in the associating delivery plan, to strengthen the UE received signal.As shown in Figure 2, data are sent to a UE in three sub-districts on identical resource, and UE receives the signal of a plurality of sub-districts simultaneously.If all home cell are sent identical data and are given UE, can promote the signal quality of UE reception from the useful signal stack of a plurality of sub-districts, thereby improve the demodulation performance of UE, especially improve the performance of cell edge UE.

The LTE system has introduced based on the precoding technique of MIMO (Multiple Input Multiple Output, multiple-input, multiple-output) channel to improve spectrum efficiency.According to the coded quantization characteristic, can be divided into CodeBook (code book/code book) and None-CodeBook (no code book/code book) dual mode, its principle is:

The CodeBook mode; System defines the code book set of the pre-coding matrix of a quantification in advance; Typically be: after UE estimates channel information according to cell common pilots like closed loop precoding mode; From set, select a pre-coding matrix by certain criterion, the criterion of choosing can be maximization mutual information, maximization output Signal to Interference plus Noise Ratio etc.UE feeds back to the base station with the index of the pre-coding matrix of selecting in code book through up channel, and this index is designated as PMI (Precoding Matrix Indicator, channel status indication).The pre-coding matrix that should use this UE just can be confirmed in the base station by the index value of receiving.

The mode of None-CodeBook; There is not the code book set of predefined quantification; Can be according to property of channel reciprocity may, the upward signal that utilizes UE to send is estimated mimo channel information; Obtain pre-coding matrix according to certain criterion then, the criterion of choosing can be maximization received signal power, maximization output Signal to Interference plus Noise Ratio etc.Owing to utilized channel reciprocity, this mode to be more suitable for system in TDD (Time Division Duplex, time division duplex).

In the multi-plot joint delivery plan; Can precoding technique be applied between a plurality of antennas of diverse location sub-district; Difference is that the foundation that pre-coding matrix is chosen is the channel information of the antenna port of a plurality of sub-districts to UE; Be equivalent to the origin-location is concentrated many antennas of 1 sub-district of (10 times wavelength distance in), expanded to the antenna of a plurality of sub-districts of position dispersion (common more than 100 meters), number of antennas and distance all have certain increase.Being called for short this technology among the application is the multi-plot joint precoding technique.

The deficiency of prior art is, in the multi-plot joint precoding technique, does not consider the situation that UE moves, and does not therefore also have corresponding processing scheme.

Summary of the invention

The invention provides a kind of definite method and device of pre-coding matrix, in order to solving prior art in the multi-plot joint precoding technique, when UE moves to definite scheme of pre-coding matrix.

A kind of definite method of pre-coding matrix is provided in the embodiment of the invention, has comprised the steps:

Confirm first channel response matrix of this measuring period;

Confirmed the second channel response matrix of a last measuring period;

Estimate that according to first channel response matrix and second channel response matrix the minizone channel phase is poor;

Said minizone channel phase difference compensated to the second channel response matrix obtain the 3rd channel response matrix;

Select pre-coding matrix according to the 3rd channel response matrix by precoding algorithm principle.

Preferably, when confirming channel response matrix, comprising:

UE confirms channel response matrix according to the public guide frequency reference symbol of sub-district;

And/or channel response matrix is confirmed according to the uplink reference symbol that UE sends in the base station.

Preferably, during according to first channel response matrix and second channel response matrix estimation minizone channel phase difference, estimate by following formula:

Δφ _2，1(0)＝Φ(H ₂(1)，H ₂(0))-Φ(H ₁(1)，H ₁(0))，

Δφ _3，1(0)＝Φ(H ₃(1)，H ₃(0))-Φ(H ₁(1)，H ₁(0))，

Wherein, (x y) is two phase differences between the channel complex response, H to function phi ₁(0), H ₂(0), H ₃(0) is first channel response matrix, H ₁(1), H ₂(1), H ₃(1) is the second channel response matrix, Δ φ _2,1(0), Δ φ _3,1(0) poor for the minizone channel phase that estimates according to first channel response matrix and second channel response matrix.

Preferably, further comprise:

Minizone channel phase difference is carried out smoothing processing.

Preferably, smoothing processing is to be undertaken by following formula:

Δφ _2，1(n)＝Φ(H ₂(n+1)，H ₂(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _2，1＝(1-λ)·Δφ _2，1+λ·Δφ _2，1(n)；

Δφ _3，1(n)＝Φ(H ₃(n+1)，H ₃(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _3，1＝(1-λ)·Δφ _3，1+λ·Δφ _3，1(n)；

Wherein, λ is a smoothing factor, Δ φ _2,1(n), Δ φ _3,1(n) poor for the minizone channel phase that estimates according to channel response matrix and the channel response matrix of the n+1 time measuring period of the n time measuring period, Δ φ _2,1, Δ φ _3,1For that estimate according to the channel response matrix of the n time measuring period and the channel response matrix of the n+1 time measuring period and poor through the minizone channel phase of smoothing processing.

Preferably, said minizone channel phase difference is compensated when the second channel response matrix obtains the 3rd channel response matrix, compensates by following formula:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}\left(0\right)},$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}\left(0\right)},$

Wherein: Δ φ _2,1(0), Δ φ _3,1(0) poor for the minizone channel phase that estimates according to first channel response matrix and second channel response matrix, H ₁(1), H ₃(1) be the second channel response matrix, It is the 3rd channel response matrix.

Preferably, said minizone channel phase difference is compensated when the second channel response matrix obtains the 3rd channel response matrix, compensates by following formula:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}},$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}},$

Wherein: H ₁(1), H ₃(1) be the second channel response matrix, It is the 3rd channel response matrix.

Preferably, said minizone channel phase difference compensated to the second channel response matrix obtains the 3rd channel response matrix, comprising:

Based on minizone channel phase difference and obtain phase change speed measuring period;

Obtain reference channel and the transmitting channel time corresponding is poor;

Confirm offset according to said phase change speed and said time difference;

Said offset compensated to the second channel response matrix obtain the 3rd channel response matrix.

A kind of definite device of pre-coding matrix also is provided in the embodiment of the invention, has comprised:

The channel response matrix module is used for confirming first channel response matrix of this measuring period, and confirms the second channel response matrix of a last measuring period;

Phase difference module is used for estimating that according to first channel response matrix and second channel response matrix the minizone channel phase is poor;

Compensating module is used for said minizone channel phase difference compensated to the second channel response matrix and obtains the 3rd channel response matrix;

Select module, be used for selecting pre-coding matrix by precoding algorithm principle according to the 3rd channel response matrix.

Preferably, when said definite device was positioned at the base station, said channel response matrix module was further used for confirming channel response matrix according to the uplink reference symbol that UE sends.

Preferably, when said definite device was positioned at subscriber equipment, said channel response matrix module was further used for confirming channel response matrix according to the public guide frequency reference symbol of sub-district.

Preferably, said phase difference module is further used for estimating that according to first channel response matrix and second channel response matrix the minizone channel phase is poor by following formula that formula is:

Δφ _2，1(0)＝Φ(H ₂(1)，H ₂(0))-Φ(H ₁(1)，H ₁(0))，

Δφ _3，1(0)＝Φ(H ₃(1)，H ₃(0))-Φ(H ₁(1)，H ₁(0))，

Wherein, (x y) is two phase differences between the channel complex response, H to function phi ₁(0), H ₂(0), H ₃(0) is first channel response matrix, H ₁(1), H ₂(1), H ₃(1) is the second channel response matrix, Δ φ _2,1(0), Δ φ _3,1(0) poor for the minizone channel phase that estimates according to first channel response matrix and second channel response matrix.

Preferably, further comprise level and smooth module, be used for minizone channel phase difference is carried out smoothing processing.

Preferably, said level and smooth module is further used for carrying out smoothing processing by following formula:

Δφ _2，1(n)＝Φ(H ₂(n+1)，H ₂(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _2，1＝(1-λ)·Δφ _2，1+λ·Δφ _2，1(n)；

Δφ _3，1(n)＝Φ(H ₃(n+1)，H ₃(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _3，1＝(1-λ)·Δφ _3，1+λ·Δφ _3，1(n)；

Wherein, λ is a smoothing factor, Δ φ _2,1(n), Δ φ _3,1(n) poor for the minizone channel phase that estimates according to channel response matrix and the channel response matrix of the n+1 time measuring period of the n time measuring period, Δ φ _2,1, Δ φ _3,1For that estimate according to the channel response matrix of the n time measuring period and the channel response matrix of the n+1 time measuring period and poor through the minizone channel phase of smoothing processing.

Preferably, said compensating module is further used for by following formula said minizone channel phase difference being compensated to the second channel response matrix and obtains the 3rd channel response matrix, and formula is:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}\left(0\right)},$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}\left(0\right)},$

Wherein: Δ φ _2,1(0), Δ φ _3,1(0) poor for the minizone channel phase that estimates according to first channel response matrix and second channel response matrix, H ₁(1), H ₃(1) be the second channel response matrix, It is the 3rd channel response matrix.

Preferably, said compensating module is further used for by following formula said minizone channel phase difference being compensated to the second channel response matrix and obtains the 3rd channel response matrix, and formula is:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}},$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}},$

Wherein: H ₁(1), H ₃(1) be the second channel response matrix,

It is the 3rd channel response matrix.

Preferably, said compensating module comprises:

Speed unit is used for according to minizone channel phase difference and obtains phase change speed measuring period;

The time difference unit is used to obtain reference channel and the transmitting channel time corresponding is poor;

The offset unit is used for confirming offset according to said phase change speed and said time difference;

Compensating unit is used for said offset compensated to the second channel response matrix and obtains the 3rd channel response matrix.

Beneficial effect of the present invention is following:

The present invention confirmed first channel response matrix of this measuring period and the second channel response matrix of a last measuring period when implementing; And estimate that according to first channel response matrix and second channel response matrix the minizone channel phase is poor; Then said minizone channel phase difference is compensated to the second channel response matrix and obtain the 3rd channel response matrix; Select pre-coding matrix according to the 3rd channel response matrix by precoding algorithm principle at last.Owing to be not as prior art, to be to select pre-coding matrix in implementing according to the second channel response matrix; But according to selecting pre-coding matrix with the 3rd channel response matrix that obtains after the compensation of minizone channel phase difference; Therefore; The deficiency that occurs irrelevance because of feedback time after postponing to cause customer location to move can be solved in the prior art, also therefore the performance of multi-plot joint precoding can be improved.

Description of drawings

Fig. 1 is a combined dispatching sketch map in the background technology;

Fig. 2 unites the transmission sketch map in the background technology;

Fig. 3 moves the variation sketch map in the embodiment of the invention with UE under the different antennae of sub-district;

Fig. 4 moves the variation sketch map for UE under the different districts different antennae in the embodiment of the invention;

Fig. 5 is definite method implementing procedure sketch map of pre-coding matrix in the embodiment of the invention;

Fig. 6 is based on the phase compensation implementing procedure sketch map of UE in the embodiment of the invention;

Fig. 7 is based on the phase compensation implementing procedure sketch map of base station in the embodiment of the invention;

Fig. 8 is definite apparatus structure sketch map of pre-coding matrix in the embodiment of the invention.

Embodiment

Describe below in conjunction with the accompanying drawing specific embodiments of the invention.

The inventor notices in the invention process: in precoding technique; No matter be to utilize the PMI of UE feedback to carry out choosing of pre-coding matrix; Still utilize uplink channel estimation information to carry out confirming of code book; The channel of institute's reference sends to final precoding during codebook selecting, all has certain delay, is generally the 10ms magnitude.Fig. 3 is for to move the variation sketch map with UE under the different antennae of sub-district; As shown in the figure; When a plurality of antennas of transmitting terminal are positioned at same website (in 10 times of wavelength of spacing); When the time of UE about 10ms was moved a less distance (1-10 centimetre) Δ d, the distance of a plurality of antennas of same website increased 1cm basically simultaneously, and signal propagates into 2 paths that different antennae experienced also to be changed basically simultaneously; So it is essentially identical for two antennas that corresponding channel phase changes; And precoding technique need solve is the relative channel response information between 2 antennas, so in this case, the delay of 10ms magnitude is little to the performance impact of precoding.

Fig. 4 moves the variation sketch map for UE under the different districts different antennae; As shown in the figure; When adopting the multi-plot joint precoding; Because different antennas is positioned at different positions; When UE moves a less distance, delta d (is example with 2cm), under the ideal situation, on the antenna 1 of sub-district 1; Propagation distance increases 2cm simultaneously; The phase change of corresponding

, and on the antenna 2 of sub-district 2, propagation distance reduces 2cm simultaneously; The phase change of corresponding

; When operating frequency was 2GHz, wavelength was 15cm to antenna phase relative variation between such two sub-districts for

, and the variation of phase place has surpassed pi/2.Generally, the UE translational speed of GSM can be up to 120km/h, just 30m/s; The feedback delay of 10ms just, the user has moved 30cm, like this; The antenna channel characteristic of two different districts is owing to small time delay reason, the channel when selecting channel and the data of the reference of pre-coding matrix institute really to send; It is very low that correlation is fastened in the relative phase pass, thereby make existing multi-plot joint precoding technique not play a role.

Given this; In 3GPP Long Term Evolution LTE-Advanced system multi-cell synergetic transmission, in the collaborative transmission of closed loop precoding, should predict and compensate owing to user after the channel latency moves the minizone phase change of bringing; Promptly; Should predict and calibrate the minizone channel phase, thus solve the user to the channel between the different districts because the irrelevance of feedback time after postponing to cause customer location to move, thereby improve the performance of multi-plot joint precoding.

Because in GSM, user movement direction and speed have certain correlation usually, in 1 second time, the variation of the direction of motion and the variation of speed are all very little.Therefore; Above-mentioned because the small location variation of user that feedback delay (10ms magnitude) brings is relatively stable, so the phase change speed of minizone antenna channel response is also relatively stable, utilizes this characteristics; Can predict this metastable phase change speed; Then according to the difference of reference channel time point and data precoding transmitting time, the channel of minizone is compensated the associating precoding that data are sent after being used at last again.Carry out the explanation of execution mode below.

Fig. 5 is definite method implementing procedure sketch map of pre-coding matrix, can comprise the steps: in the enforcement

Step 501, confirm first channel response matrix of this measuring period;

The second channel response matrix of step 502, a definite last measuring period;

Step 503, poor according to first channel response matrix and second channel response matrix estimation minizone channel phase;

Step 504, said minizone channel phase difference compensated to the second channel response matrix obtain the 3rd channel response matrix;

Step 505, select pre-coding matrix by precoding algorithm principle according to the 3rd channel response matrix.

In the enforcement, when step 501,502 is confirmed channel response matrix, can comprise:

UE confirms channel response matrix according to the public guide frequency reference symbol of sub-district;

And/or channel response matrix is confirmed according to the uplink reference symbol that UE sends in the base station.

Be to confirm pre-coding matrix owing to confirm the purpose of channel response matrix during the present invention implements; And definite minizone channel phase is poor, therefore, and in the practical implementation; Except aforesaid way, other modes that can be used in definite channel response matrix of this purpose also can adopt.

Step 503 estimate minizone channel phase difference according to first channel response matrix and second channel response matrix the time, can be undertaken by following formula:

Δφ _2，1(0)＝Φ(H ₂(1)，H ₂(0))-Φ(H ₁(1)，H ₁(0))，

Δφ _3，1(0)＝Φ(H ₃(1)，H ₃(0))-Φ(H ₁(1)，H ₁(0))，

Wherein, (x y) is two phase differences between the channel complex response, H to function phi ₁(0), H ₂(0), H ₃(0) is first channel response matrix, H ₁(1), H ₂(1), H ₃(1) is the second channel response matrix.

For the prediction of minizone channel phase difference, can also adopt certain smoothing factor λ to carry out smoothing processing, can further include in therefore implementing:

Minizone channel phase difference is carried out smoothing processing.

Concrete smoothing processing can be undertaken by following formula:

Δφ _2，1(n)＝Φ(H ₂(n+1)，H ₂(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _2，1＝(1-λ)·Δφ _2，1+λ·Δφ _2，1(n)；

Δφ _3，1(n)＝Φ(H ₃(n+1)，H ₃(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _3，1＝(1-λ)·Δφ _3，1+λ·Δφ _3，1(n)；

Wherein, λ is a smoothing factor.Smoothing factor is generally got a representative value between (0-1) in the enforcement, as 0.25,0.125 etc., can certainly adjust according to the correlation of scene and phase change.

Adopt the smoothing processing of other mode also to be fine in the enforcement, for example use the formula of other various known smothing filterings to carry out smoothing processing.

In step 504 said minizone channel phase difference is compensated to the second channel response matrix and to obtain in the 3rd channel response matrix, can be undertaken by following formula:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}\left(0\right)},$

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}\left(0\right)},$

Wherein: Δ φ _2,1(0), Δ φ _3,1(0) poor for the minizone channel phase that estimates according to first channel response matrix and second channel response matrix, H ₁(1), H ₃(1) be the second channel response matrix,

It is the 3rd channel response matrix.

Above processing be the execution mode under situation uniformly-spaced, down in the face of not being that compensation execution mode under the equally spaced situation describes.

Said minizone channel phase difference compensated to the second channel response matrix obtains the 3rd channel response matrix, can also comprise:

Based on minizone channel phase difference and obtain phase change speed measuring period, in the enforcement, a kind of simple mode is can obtain phase change speed with minizone channel phase difference after divided by measuring period;

Obtain reference channel and the transmitting channel time corresponding is poor;

Obtain this time difference and be because the precoding vector above the transmitting channel is based on the channel estimation value that reference channel obtains and calculate; That is to say that elder generation obtains precoding according to the reference channel in the moment 1; Be used for then 2 removing to send signal, this value that this time difference just is meant constantly.

Confirm offset according to said phase change speed and said time difference, in the enforcement, a kind of simple mode is phase change speed to be multiply by the time difference just can determine offset;

Said offset compensated to the second channel response matrix obtain the 3rd channel response matrix.

It is thus clear that, when phase compensation,, can obtain phase change speed with phase change divided by the time if not equally spaced scheduling and prediction, the speed of phase change multiply by reference channel and the transmitting channel time corresponding difference value of being compensated.

After compensation, obtain the 3rd channel response matrix; Compare with the second channel matrix, obviously this matrix has considered that feedback time postpones institute's influence in generation, therefore;, step 505 just can solve user above-mentioned when selecting pre-coding matrix according to the 3rd channel response matrix to the channel between the different districts; Because feedback time postpones, the deficiency of the irrelevance after customer location moves can improve the performance of multi-plot joint precoding.

Routine with UE respectively, base station side more below embodiment describes.

Embodiment one

Fig. 6 is the phase compensation implementing procedure sketch map based on UE, and is as shown in the figure, can comprise:

After step 601, UE insert, the public guide frequency reference symbol of the COMP sub-district that the reception network side issues.

Step 602, UE are measured the channel complex response matrix from a plurality of antenna in cell according to the public guide frequency reference symbol of sub-district.

Associating precoding with 3 sub-districts in the enforcement is an example, is respectively H ₁(0), H ₂(0), H ₃(0).

Step 603, UE according to precoding algorithm principle, select pre-coding matrix according to above channel response matrix, and feedback.

After step 604, the elapsed time cycle T, UE measures the channel complex response matrix from a plurality of antenna in cell once more.

Be designated as H in the enforcement respectively ₁(1), H ₂(1), H ₃(1);

Cycle can be got 10ms in force usually; Be that 10ms only is used to instruct specifically embodiment of the present invention how of those skilled in the art with the T value in force; But do not mean only can use to be set to 10ms one value, can combine demand in practice to confirm corresponding value in the implementation process.

Step 605, UE estimate that according to the channel response of twice of front and back the minizone channel phase is poor.

Can be undertaken by following formula in the practical implementation:

Δφ _2，1(0)＝Φ(H ₂(1)，H ₂(0))-Φ(H ₁(1)，H ₁(0))，

Δ φ _3,1(0)=Φ (H ₃(1), H ₃(0))-Φ (H ₁(1), H ₁(0)) formula (1)

Wherein, (x y) for calculating the phase difference between two channel complex responses, as channel response x, when y is matrix, can get the phase difference of corresponding element to function phi, and correspondence is output as the phase difference matrix.

Step 606, with the phase difference of top estimation, compensate on the channel response matrix, according to precoding algorithm principle, select the precoding square to fall, and feedback.

In the enforcement, the channel response matrix of compensation is H ₂(1), H ₃(1) on;

According to precoding algorithm principle, when selecting pre-coding matrix, identical with step 603;

Specifically when compensation, can compensate by following formula:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}\left(0\right)}$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{J\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}\left(0\right)}$ Formula (2)

Work as H ₂(1), H ₃When (1) being matrix, above computing is multiplied each other for the matrix corresponding element.

In the operation of UE repeating step 604 to step 606, for the prediction of minizone channel phase difference,

Can adopt certain smoothing factor λ to carry out smoothing processing, specifically can adopt following formula:

Δφ _2，1(n)＝Φ(H ₂(n+1)，H ₂(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _2，1＝(1-λ)·Δφ _2，1+λ·Δφ _2，1(n)

Δφ _3，1(n)＝Φ(H ₃(n+1)，H ₃(n))-Φ(H ₁(n+1)，H ₁(n))

Δ φ _3,1=(1-λ) Δ φ _3,1+ λ Δ φ _3,1(n) formula (3)

Embodiment two

Phase compensation mode principle based on the base station is identical with UE phase compensation, and just channel response is estimated according to up channel in the base station, and the predicted phase rotation.

Fig. 7 is the phase compensation implementing procedure sketch map based on the base station, and is as shown in the figure, can comprise:

After step 701, UE inserted, network was according to certain dispatching method, and scheduling UE sends uplink reference symbol.

The uplink reference symbol that send according to UE step 702, each sub-district is estimated channel response.

Associating precoding with 3 sub-districts in the enforcement is an example, is respectively H ₁(0), H ₂(0), H ₃(0).

Step 703, merge the sub-district channel response matrix is passed to the home cell of UE, home cell, is selected pre-coding matrix, and is notified each COMP sub-district according to precoding algorithm principle according to above channel response matrix.

After step 704, the elapsed time cycle T, UE is measured once more to each self-channel complex response matrix in each sub-district, and channel response is passed to home cell.

The matrix that to measure once more in the enforcement is designated as: H ₁(1), H ₂(1), H ₃(1).

Step 705, home cell estimate that according to the channel response of twice of front and back the minizone channel phase is poor.

Can be undertaken by following formula in the practical implementation:

Δφ _2，1(0)＝Φ(H ₂(1)，H ₂(0))-Φ(H ₁(1)，H ₁(0))，

Δ φ _3,1(0)=Φ (H ₃(1), H ₃(0))-Φ (H ₁(1), H ₁(0)) formula (1)

Wherein, (x y) for calculating the phase difference between two channel complex responses, as channel response x, when y is matrix, can get the phase difference of corresponding element to function phi, and correspondence is output as the phase difference matrix.

Step 706, with the phase difference of top estimation, compensate on the channel response matrix, according to precoding algorithm principle, select pre-coding matrix, and notify each COMP sub-district.

In the enforcement, the channel response matrix of compensation is H ₂(1), H ₃(1) on;

According to precoding algorithm principle, when selecting pre-coding matrix, identical with step 603;

Specifically when compensation, can compensate by following formula:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}\left(0\right)}$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{J\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}\left(0\right)}$ Formula (2)

Work as H ₂(1), H ₃When (1) being matrix, above computing is multiplied each other for the matrix corresponding element.

In the operation of base station repeating step 704 to 706, for the prediction of minizone channel phase difference, can adopt certain smoothing factor λ to carry out smoothing processing, specifically can adopt following formula:

Δφ _2，1(n)＝Φ(H ₂(n+1)，H ₂(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _2，1＝(1-λ)·Δφ _2，1+λ·Δφ _2，1(n)

Δφ _3，1(n)＝Φ(H ₃(n+1)，H ₃(n))-Φ(H ₁(n+1)，H ₁(n))

Δ φ _3,1=(1-λ) Δ φ _3,1+ λ Δ φ _3,1(n) formula (3)

Based on same inventive concept; A kind of definite device of pre-coding matrix also is provided in the embodiment of the invention; Because the principle of this device solves problem is similar with definite method of pre-coding matrix, so the enforcement of this device can repeat part and not give unnecessary details referring to the enforcement of method.

Fig. 8 is definite apparatus structure sketch map of pre-coding matrix, and is as shown in the figure, confirms can comprise in the device:

Channel response matrix module 801 is used for confirming first channel response matrix of this measuring period, and confirms the second channel response matrix of a last measuring period;

Phase difference module 802 is used for estimating that according to first channel response matrix and second channel response matrix the minizone channel phase is poor;

Compensating module 803 is used for said minizone channel phase difference compensated to the second channel response matrix and obtains the 3rd channel response matrix;

Select module 804, be used for selecting pre-coding matrix by precoding algorithm principle according to the 3rd channel response matrix.

During enforcement, channel response matrix module 801 is confirmed first channel response matrix of this measuring period, and the second channel response matrix of confirming a last measuring period; Phase difference module 802 estimates that according to first channel response matrix and second channel response matrix the minizone channel phase is poor then; Compensating module 803 compensates minizone channel phase difference to the second channel response matrix and obtains the 3rd channel response matrix; Selecting module 804 at last is to select pre-coding matrix according to the 3rd channel response matrix by precoding algorithm principle, rather than as prior art, selects pre-coding matrix according to the second channel response matrix by precoding algorithm principle.

In the utilization of confirming device, can device be installed in UE and go up use, also can be installed in and supply the base station use on the base station, can know through embodiment one and two:

When definite device was positioned on the base station, the channel response matrix module can be further used for confirming channel response matrix based on the uplink reference symbol that UE sends.

When definite device was positioned on the subscriber equipment, the channel response matrix module can be further used for confirming channel response matrix according to the public guide frequency reference symbol of sub-district.

In the enforcement, phase difference module can be further used for estimating that according to first channel response matrix and second channel response matrix the minizone channel phase is poor by following formula that formula is:

Δφ _2，1(0)＝Φ(H ₂(1)，H ₂(0))-Φ(H ₁(1)，H ₁(0))，

Δφ _3，1(0)＝Φ(H ₃(1)，H ₃(0))-Φ(H ₁(1)，H ₁(0))，

Wherein, (x y) is two phase differences between the channel complex response, H to function phi ₁(0), H ₂(0), H ₃(0) is first channel response matrix, H ₁(1), H ₂(1), H ₃(1) is the second channel response matrix.

Confirm to can further include in the device level and smooth module 805, link to each other, be used for minizone channel phase difference is carried out smoothing processing with phase difference module.

Level and smooth module can also be further used for carrying out smoothing processing by following formula:

Δφ _2，1(n)＝Φ(H ₂(n+1)，H ₂(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _2，1＝(1-λ)·Δφ _2，1+λ·Δφ _2，1(n)；

Δφ _3，1(n)＝Φ(H ₃(n+1)，H ₃(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _3，1＝(1-λ)·Δφ _3，1+λ·Δφ _3，1(n)；

Wherein, λ is a smoothing factor.

In the enforcement, compensating module can be further used for by following formula said minizone channel phase difference being compensated to the second channel response matrix and obtain the 3rd channel response matrix, and formula is:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}\left(0\right)},$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}\left(0\right)},$

Wherein: Δ φ _2,1(0), Δ φ _3,1(0) poor for the minizone channel phase that estimates according to first channel response matrix and second channel response matrix, H ₁(1), H ₃(1) be the second channel response matrix,

It is the 3rd channel response matrix.

Above-mentioned compensating module is the execution mode under the equidistant situation, introduces the compensating module under the non-equidistance below, and compensating module comprises in this scheme:

Speed unit is used for according to minizone channel phase difference and obtains phase change speed measuring period;

The time difference unit is used to obtain reference channel and the transmitting channel time corresponding is poor;

The offset unit is used for confirming offset according to said phase change speed and said time difference;

Compensating unit is used for said offset compensated to the second channel response matrix and obtains the 3rd channel response matrix.

For the convenience of describing, the each several part of the above device is divided into various modules with function or the unit is described respectively.Certainly, when embodiment of the present invention, can in same or a plurality of softwares or hardware, realize the function of each module or unit.

Visible by above-mentioned execution mode; The scheme of the associating precoding that the present invention provides in implementing; After prediction UE changes to the channel phase between the diverse location antenna in cell; To the reference channel of estimating, just utilize the channel parameter after compensating to carry out the calculating of pre-coding matrix then the Phase Shift Offset of predicting, and be used for later data transmission.Owing to actually carry out channel that pre-coding matrix confirms through overcompensation, therefore just can solve the deficiency that occurs irrelevance after customer location that feedback time postpones to cause moves, also therefore can improve the performance of multi-plot joint precoding.

Further, predict that each cell channel phase change can be by UE based on down channel estimated value prediction, like public guide frequency reference symbol prediction based on the sub-district, also can be by network based on the uplink channel estimation value prediction, as predicting based on uplink reference symbol;

Further, the scheme that also provides prediction minizone channel phase to change in the enforcement is: based on the corresponding channel response of historical each some cycle time, ask the phase difference of each corresponding each element in the channel response matrix, and concrete processing formula, like formula (1);

Further, can also carry out smoothing processing according to certain smoothing factor to the phase difference of each prediction, and concrete processing formula, like formula (3);

Further, also provide the scheme of phase compensation to be in the enforcement: to each element of channel response matrix, and concrete processing formula is like formula (2) with the phase difference compensation of prediction;

Further, when phase compensation,, can obtain phase change speed, the speed of phase change multiply by reference channel and the transmitting channel time corresponding difference value of being compensated with phase change divided by the time if not equally spaced scheduling and prediction.

It is thus clear that each technical scheme among the embodiment can effectively compensate the minizone of diverse location owing to the influence that the corresponding slight distance of UE feedback delay moves the phase change of bringing, and can improve the performance of multi-plot joint transfer of data.

Those skilled in the art should understand that embodiments of the invention can be provided as method, system or computer program.Therefore, the present invention can adopt the form of the embodiment of complete hardware embodiment, complete software implementation example or combination software and hardware aspect.And the present invention can be employed in the form that one or more computer-usable storage medium (including but not limited to magnetic disc store, CD-ROM, optical memory etc.) that wherein include computer usable program code go up the computer program of implementing.

The present invention is that reference is described according to the flow chart and/or the block diagram of method, equipment (system) and the computer program of the embodiment of the invention.Should understand can be by the flow process in each flow process in computer program instructions realization flow figure and/or the block diagram and/or square frame and flow chart and/or the block diagram and/or the combination of square frame.Can provide these computer program instructions to the processor of all-purpose computer, special-purpose computer, Embedded Processor or other programmable data processing device to produce a machine, make the instruction of carrying out through the processor of computer or other programmable data processing device produce to be used for the device of the function that is implemented in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame appointments.

These computer program instructions also can be stored in ability vectoring computer or the computer-readable memory of other programmable data processing device with ad hoc fashion work; Make the instruction that is stored in this computer-readable memory produce the manufacture that comprises command device, this command device is implemented in the function of appointment in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame.

These computer program instructions also can be loaded on computer or other programmable data processing device; Make on computer or other programmable devices and to carry out the sequence of operations step producing computer implemented processing, thereby the instruction of on computer or other programmable devices, carrying out is provided for being implemented in the step of the function of appointment in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame.

Although described the preferred embodiments of the present invention, in a single day those skilled in the art get the basic inventive concept could of cicada, then can make other change and modification to these embodiment.So accompanying claims is intended to be interpreted as all changes and the modification that comprises preferred embodiment and fall into the scope of the invention.Obviously, those skilled in the art can carry out various changes and modification to the present invention and not break away from the spirit and scope of the present invention.Like this, belong within the scope of claim of the present invention and equivalent technologies thereof if of the present invention these are revised with modification, then the present invention also is intended to comprise these changes and modification interior.

Claims (17)

1. definite method of a pre-coding matrix is characterized in that, comprises the steps:

Confirm first channel response matrix of this measuring period;

Confirmed the second channel response matrix of a last measuring period;

Estimate that according to first channel response matrix and second channel response matrix the minizone channel phase is poor;

Said minizone channel phase difference compensated to the second channel response matrix obtain the 3rd channel response matrix;

Select pre-coding matrix according to the 3rd channel response matrix by precoding algorithm principle.

2. the method for claim 1 is characterized in that, when confirming channel response matrix, comprising:

UE confirms channel response matrix according to the public guide frequency reference symbol of sub-district;

And/or channel response matrix is confirmed according to the uplink reference symbol that UE sends in the base station.

3. the method for claim 1 is characterized in that, during according to first channel response matrix and second channel response matrix estimation minizone channel phase difference, estimates by following formula:

Δφ _2，1(0)＝Φ(H ₂(1)，H ₂(0))-Φ(H ₁(1)，H ₁(0))，

Δφ _3，1(0)＝Φ(H ₃(1)，H ₃(0))-Φ(H ₁(1)，H ₁(0))，

Wherein, (x y) is two phase differences between the channel complex response, H to function phi ₁(0), H ₂(0), H ₃(0) is first channel response matrix, H ₁(1), H ₂(1), H ₃(1) is the second channel response matrix, Δ φ _2,1(0), Δ φ _3,1(0) poor for the minizone channel phase that estimates according to first channel response matrix and second channel response matrix.

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

Minizone channel phase difference is carried out smoothing processing.

5. method as claimed in claim 4 is characterized in that, smoothing processing is undertaken by following formula:

Δφ _2，1(n)＝Φ(H ₂(n+1)，H ₂(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _2，1＝(1-λ)·Δφ _2，1+λ·Δφ _2，1(n)；

Δφ _3，1(n)＝Φ(H ₃(n+1)，H ₃(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _3，1＝(1-λ)·Δφ _3，1+λ·Δφ _3，1(n)；

Wherein, λ is a smoothing factor, Δ φ _2,1(n), Δ φ _3,1(n) poor for the minizone channel phase that estimates according to channel response matrix and the channel response matrix of the n+1 time measuring period of the n time measuring period, Δ φ _2,1, Δ φ _3,1For that estimate according to the channel response matrix of the n time measuring period and the channel response matrix of the n+1 time measuring period and poor through the minizone channel phase of smoothing processing.

6. like the arbitrary described method of claim 1 to 4, it is characterized in that, said minizone channel phase difference compensated when the second channel response matrix obtains the 3rd channel response matrix, compensate by following formula:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}\left(0\right)},$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}\left(0\right)},$

Wherein: Δ φ _2,1(0), Δ φ _3,1(0) poor for the minizone channel phase that estimates according to first channel response matrix and second channel response matrix, H ₂(1), H ₃(1) be the second channel response matrix,

It is the 3rd channel response matrix.

7. method as claimed in claim 5 is characterized in that, said minizone channel phase difference is compensated when the second channel response matrix obtains the 3rd channel response matrix, compensates by following formula:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}},$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}},$

Wherein: H ₂(1), H ₃(1) be the second channel response matrix,

It is the 3rd channel response matrix.

8. like the arbitrary described method of claim 1 to 5, it is characterized in that, said minizone channel phase difference compensated to the second channel response matrix obtain the 3rd channel response matrix, comprising:

Based on minizone channel phase difference and obtain phase change speed measuring period;

Obtain reference channel and the transmitting channel time corresponding is poor;

Confirm offset according to said phase change speed and said time difference;

Said offset compensated to the second channel response matrix obtain the 3rd channel response matrix.

9. definite device of a pre-coding matrix is characterized in that, comprising:

The channel response matrix module is used for confirming first channel response matrix of this measuring period, and confirms the second channel response matrix of a last measuring period;

Phase difference module is used for estimating that according to first channel response matrix and second channel response matrix the minizone channel phase is poor;

Compensating module is used for said minizone channel phase difference compensated to the second channel response matrix and obtains the 3rd channel response matrix;

Select module, be used for selecting pre-coding matrix by precoding algorithm principle according to the 3rd channel response matrix.

10. definite device as claimed in claim 9 is characterized in that, when said definite device was positioned at the base station, said channel response matrix module was further used for confirming channel response matrix according to the uplink reference symbol that UE sends.

11. definite device as claimed in claim 9 is characterized in that, when said definite device was positioned at subscriber equipment, said channel response matrix module was further used for confirming channel response matrix according to the public guide frequency reference symbol of sub-district.

12. definite device as claimed in claim 9 is characterized in that, said phase difference module is further used for estimating that according to first channel response matrix and second channel response matrix the minizone channel phase is poor by following formula that formula is:

Δφ _2，1(0)＝Φ(H ₂(1)，H ₂(0))-Φ(H ₁(1)，H ₁(0))，

Δφ _3，1(0)＝Φ(H ₃(1)，H ₃(0))-Φ(H ₁(1)，H ₁(0))，

Wherein, (x y) is two phase differences between the channel complex response, H to function phi ₁(0), H ₂(0), H ₃(0) is first channel response matrix, H ₁(1), H ₂(1), H ₃(1) is the second channel response matrix, Δ φ _2,1(0), Δ φ _3,1(0) poor for the minizone channel phase that estimates according to first channel response matrix and second channel response matrix.

13. definite device as claimed in claim 12 is characterized in that, further comprises level and smooth module, is used for minizone channel phase difference is carried out smoothing processing.

14. definite device as claimed in claim 13 is characterized in that, said level and smooth module is further used for carrying out smoothing processing by following formula:

Δφ _2，1(n)＝Φ(H ₂(n+1)，H ₂(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _2，1＝(1-λ)·Δφ _2，1+λ·Δφ _2，1(n)；

Δφ _3，1(n)＝Φ(H ₃(n+1)，H ₃(n))-Φ(H ₁(n+1)，H ₁(n))，

Δφ _3，1＝(1-λ)·Δφ _3，1+λ·Δφ _3，1(n)；

Wherein, λ is a smoothing factor, Δ φ _2,1(n), Δ φ _3,1(n) poor for the minizone channel phase that estimates according to channel response matrix and the channel response matrix of the n+1 time measuring period of the n time measuring period, Δ φ _2,1, Δ φ _3,1For that estimate according to the channel response matrix of the n time measuring period and the channel response matrix of the n+1 time measuring period and poor through the minizone channel phase of smoothing processing.

15., it is characterized in that said compensating module is further used for by following formula said minizone channel phase difference being compensated to the second channel response matrix and obtains the 3rd channel response matrix like the arbitrary described definite device of claim 9 to 13, formula is:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}\left(0\right)},$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}\left(0\right)},$

Wherein: Δ φ _2,1(0), Δ φ _3,1(0) poor for the minizone channel phase that estimates according to first channel response matrix and second channel response matrix, H ₂(1), H ₃(1) be the second channel response matrix,

It is the 3rd channel response matrix.

16. definite device as claimed in claim 14 is characterized in that, said compensating module is further used for by following formula said minizone channel phase difference being compensated to the second channel response matrix and obtains the 3rd channel response matrix, and formula is:

${\hat{H}}_2\left(1\right)=H_2\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{2,1}}},$

${\hat{H}}_3\left(1\right)=H_3\left(1\right)\·e^{-\mathrm{j\Δ}{\mathrm{\φ}}_{\mathrm{3,1}}},$

Wherein: H ₂(1), H ₃(1) be the second channel response matrix,

It is the 3rd channel response matrix.

17., it is characterized in that said compensating module comprises like the arbitrary described definite device of claim 9 to 14:

Speed unit is used for according to minizone channel phase difference and obtains phase change speed measuring period;

The time difference unit is used to obtain reference channel and the transmitting channel time corresponding is poor;

The offset unit is used for confirming offset according to said phase change speed and said time difference;

Compensating unit is used for said offset compensated to the second channel response matrix and obtains the 3rd channel response matrix.

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