CN104113367A - Feedback method in blended collaborative multipoint transmission system and related user equipment - Google Patents

Abstract

The invention discloses a feedback method executed by user equipment in a blended CoMP system and related user equipment. The method comprises the following steps: reference signals from a plurality of wireless transceiver stations are received; channel estimation is performed based on the received reference signals to obtain quantized channel direction information of the channel between the user equipment and each wireless transceiver station; the quantized channel direction information is fed back to each wireless transceiver station; special orthogonal reference signals or control signaling from the plurality of wireless transceiver stations are received; channel estimation is performed based on the received special orthogonal reference signals or control signalling to obtain quantized phase difference information between signals of wireless transceiver stations executing united launch JT; and the quantized phase difference information is fed back to a reference wireless transceiver station in the wireless transceiver stations. The invention further discloses a communication method which is used by combining with the feedback method and executed by the reference wireless transceiver station in the blended CoMP system and related wireless transceiver stations.

Description

Feedback method in mixing cooperative multicast system and relevant subscriber equipment

Technical field

The present invention relates to radio communication cooperative multipoint transmission (CoMP) technical field, be specifically related to the feedback method carried out by subscriber equipment in mixed C oMP system and relevant subscriber equipment, also relate to the communication means of being carried out by the reference wireless receiving and dispatching station in mixed C oMP system that is combined with to feedback method and relevant wireless receiving and dispatching station.

Background technology

Cooperative multipoint transmission (CoMP) is the multiple multipoint cooperative modes such as different radio frequency access point (RRU) cooperation in community, community and other affiliated relay cooperatives, minizone cooperation of passing through that propose around the target of IMT Advanced, reduces cell edge and disturbs, improves cell edge spectrum efficiency, increases effective technical measures that cover.

CoMP technology can be considered as multiple nodes to be controlled by the virtual unit of certain Centroid or super node, its shared data, channel condition information, and simultaneously, penetrate with taking place frequently.In order to make shared channel state information between multiple wireless receiving and dispatchings station, often adopt and quantize feedback technique, by the mode of feedback code book code word sequence number, make wireless receiving and dispatching station obtain impaction of partial channel state information, thereby go up the feedback overhead of minimizing system largely.

In the MU-MIMO system of Dan community, traditional quantification feedback technique, by channel directional information (CDI) and channel quality information (CQI) after feedback quantization, can obtain good systematic function.But, in CoMP system, continue to use traditional quantification feedback technique and may cause subscriber equipment, in the time receiving the signal of multiple wireless receiving and dispatchings station transmitting, the effect of signal cancellation occurs, thereby cause the decline of systematic function.

Summary of the invention

In view of apply the above defect of conventional quantization feedback technique in CoMP system, the object of the invention is to: propose feedback method that the subscriber equipment in a kind of mixed C oMP system of novelty carries out and relevant subscriber equipment, overcome the phase fuzzy problem that multicast communication causes, make user side receive signal coherence stack.

Another object of the present invention is to propose the communication means by the reference wireless receiving and dispatching station execution in mixed C oMP system that the feedback method novel to this be combined with and relevant wireless receiving and dispatching station.

For achieving the above object, according to a first aspect of the invention, provide a kind of feedback method of being carried out by the subscriber equipment in mixed C oMP system, comprised the following steps: i) receive the reference signal from multiple wireless receiving and dispatchings station; Ii) carry out channel estimating based on the reference signal receiving, obtain the channel directional information after the quantification of the channel between this subscriber equipment and each wireless receiving and dispatching station; Iii) the channel directional information after quantizing is fed back to each wireless receiving and dispatching station; Iv) receive special orthogonal reference signal or the control signal from multiple wireless receiving and dispatchings station, described special orthogonal reference signal is to adopt for the precoding of subscriber equipment structure to launch, and described control signal is the precoding for subscriber equipment structure to notification of user equipment; V) the special orthogonal reference signal based on receiving or control signal carry out channel estimating, obtain from the phase information after the quantification of carrying out between the signal at wireless receiving and dispatching station of JT; And vi) phase information after quantizing is fed back to the reference wireless receiving and dispatching station in wireless receiving and dispatching station.

By associating feedback channel directional information and phase information, be respectively cooperative scheduling/collaborative wave beam forming (CS/CB at the cooperation mode at wireless receiving and dispatching station, Coordinated scheduling/beamforming) and multi-point joint transmitting (JT, Joint Transmission) mixed C oMP system in, wireless receiving and dispatching station can be adjusted by precoding phase place, overcome the phase fuzzy problem that multicast communication causes, make user side receive signal coherence stack.

Preferably, for subscriber equipment k, be as the criterion with following formula, point be used in to the bit number B of the channel directional information after the l feedback quantization of each wireless receiving and dispatching station _lbit number P with the phase information for to reference to after the feedback quantization of wireless receiving and dispatching station ₁:

max SINR _k

$\begin{array}{cc}s.t& \underset{l}{\mathrm{\Σ}}\end{array}{B}_l+P_1=B$

Wherein, B represents total number of bits of feedback that subscriber equipment k can be used for feeding back.

Based on the feedback overhead of above-mentioned allocation criteria reasonable distribution channel directional information and phase information, can when merging the impact that disappears mutually, improve the receiving end signal that reduces to cause because of phase ambiguity the utilization ratio of feedback bits.

Preferably, the step I of method according to a first aspect of the invention i) further comprises: calculate the channel information between each wireless receiving and dispatching station l and subscriber equipment k ; According to calculate normalized channel directional information; And according to by normalized channel directional information be quantified as B _lchannel directional information after the quantification of bit wherein, represent the code book of channel directional information, wherein, the complex space that represents N*M, N and M represent respectively the number of antennas of subscriber equipment k and wireless receiving and dispatching station l.

Preferably, v) further comprise according to the step of the method for first aspect present invention: according to calculate from the phase place angle of carrying out between the signal at each wireless receiving and dispatching station of JT, wherein, for the fixed phase with reference to wireless receiving and dispatching station; And according to by phase place angle theta _kbe quantified as P ₁phase information after the quantification of bit wherein, represent phase place code book, wherein,

According to a second aspect of the invention, provide a kind of communication means of being carried out by the reference wireless receiving and dispatching station of mixing in cooperative multicast system, having comprised: i) with reference to wireless receiving and dispatching station l _refreceive the channel directional information from the quantification of subscriber equipment k feedback ii) the channel directional information after the quantification based on receiving structure precoding; Iii) receive the phase information from the quantification of subscriber equipment k feedback and iv) phase information after quantification based on receiving carry out precoding phase compensation.

Preferably, i) further comprise according to the step I of the method for second aspect present invention: according to by the channel directional information polymerization after the quantification receiving; According to the transmitting pre-coding matrix of structure wireless receiving and dispatching station l; And right be normalized, and obtain after normalization k row, as with reference to wireless receiving and dispatching station l _refthe precoding for user k

Preferably, according to the step I of second aspect present invention v) in, according to carry out precoding phase compensation.

According to a third aspect of the invention we, a kind of subscriber equipment is provided, comprise: signal receiving unit, for receiving the reference signal from multiple wireless receiving and dispatchings station, described signal receiving unit is also for receiving special orthogonal reference signal or the control signal from multiple wireless receiving and dispatchings station, described special orthogonal reference signal is to adopt the precoding for subscriber equipment of constructing to launch, the precoding for subscriber equipment that described control signal is constructed to notification of user equipment; Channel directional information estimates and quantifying unit, for carrying out channel estimating according to the reference signal that receives, obtains the channel directional information after the quantification of the channel between this subscriber equipment and each wireless receiving and dispatching station; Feedback unit, for feeding back to each wireless receiving and dispatching station by the channel directional information after quantizing; And phase information estimates and quantifying unit, for carrying out channel estimating according to the special orthogonal reference signal or the control signal that receive, obtain from the phase information after the quantification of carrying out between the signal at wireless receiving and dispatching station of JT; Wherein, described feedback unit further feeds back to the reference wireless receiving and dispatching station in wireless receiving and dispatching station by the phase information after quantizing.

Preferably, comprise according to the estimation of channel directional information and the quantifying unit of the subscriber equipment of third aspect present invention: channel information calculating part, for calculating the channel information between each wireless receiving and dispatching station l and subscriber equipment k normalization channel directional information calculating part, for basis calculate normalized channel directional information; And quantized channel directional information calculating part, for basis by normalized channel directional information be quantified as the channel directional information after the quantification of Bl bit wherein, represent the code book of channel directional information, wherein, the complex space that represents N*M, N and M represent respectively the number of antennas of subscriber equipment k and wireless receiving and dispatching station l.

Preferably, comprise according to phase information estimation and the quantifying unit of the subscriber equipment of third aspect present invention: phase place angle calculating part, for basis calculate from the phase place angle of carrying out between the signal at each wireless receiving and dispatching station of JT, wherein, for the fixed phase with reference to wireless receiving and dispatching station; And the poor information calculating part of Quantization phase, for basis by phase place angle theta _kbe quantified as P ₁phase information after the quantification of bit wherein, represent phase place code book, wherein,

According to a forth aspect of the invention, provide a kind of wireless receiving and dispatching station, having comprised: feedback information receiving element, for reference to wireless receiving and dispatching station l _refreceive the channel directional information from the quantification of subscriber equipment k feedback described feedback information receiving element also receives the phase information from the quantification of subscriber equipment k feedback precoding unit, for the channel directional information after the quantification based on receiving structure precoding; And precoding phase compensation unit, for the phase information after the quantification based on receiving carry out precoding phase compensation.

Preferably, comprise according to the precoding unit in the wireless receiving and dispatching station of fourth aspect present invention: channel directional information converging portion, for basis by the channel directional information polymerization after the quantification receiving; Pre-coding matrix structure portion, for basis the transmitting pre-coding matrix of structure wireless receiving and dispatching station l; And precoding forming portion, for right be normalized, and obtain after normalization k row, as with reference to wireless receiving and dispatching station l _refthe precoding for user k

Brief description of the drawings

By below in conjunction with brief description of the drawings the preferred embodiments of the present invention, will make of the present invention above-mentioned and other objects, features and advantages are clearer, wherein:

Fig. 1 shows the schematic diagram that can apply according to the mixed C oMP system of feedback method of the present invention;

Fig. 2 shows according to the flow chart of the feedback method of being carried out by the subscriber equipment in CoMP system of the present invention;

Fig. 3 shows according to the flow chart of the communication means of being carried out by the reference wireless receiving and dispatching station in CoMP system of the present invention;

Fig. 4 shows the schematic construction block diagram according to subscriber equipment of the present invention; And

Fig. 5 shows according to the schematic construction block diagram at wireless receiving and dispatching of the present invention station.

Embodiment

To a preferred embodiment of the present invention will be described in detail, in description process, having omitted is unnecessary details and function for the present invention with reference to the accompanying drawings, obscures to prevent that the understanding of the present invention from causing.

Fig. 1 shows the schematic diagram that can apply according to the mixed C oMP system of feedback method of the present invention.As shown in the figure, the coverage of community 1,3 falls in the coverage of community 2, and user k is positioned at the coverage of community 1 thereby is also positioned at the coverage of community 2.For user k, be CS/CB for community 1,3 provides the cooperation mode between the wireless receiving and dispatching station of wireless coverage, and between the wireless receiving and dispatching station of community 1,2, cooperation mode is JT.The number of transmit antennas at wireless receiving and dispatching station is M, and user's reception antenna number is N, number of users K, and total number of bits of feedback of user is B.It should be noted that, for the purpose of simple and clear, in Fig. 1, only show the CoMP system that comprises three wireless receiving and dispatching stations, it will be understood by those skilled in the art that method and apparatus of the present invention disclosed herein is applicable to the CoMP system that comprises three or more wireless receiving and dispatching stations.

Fig. 2 shows the feedback method of being carried out by the subscriber equipment mixing in cooperative multipoint transmission (CoMP) system according to of the present invention.As shown in Figure 2, the method originates in step S210, and wherein, subscriber equipment receives the reference signal from multiple wireless receiving and dispatchings station.Then, method advances to step S220.

In step S220, subscriber equipment carries out channel estimating based on the reference signal receiving, and obtains the channel directional information after the quantification of the channel between this subscriber equipment and each wireless receiving and dispatching station.

As the example implementation of obtaining the channel directional information after quantification, first subscriber equipment calculates the channel information between each wireless receiving and dispatching station l and subscriber equipment k then, according to calculate normalized channel directional information.Finally, according to by normalized channel directional information be quantified as B _lchannel directional information after the quantification of bit wherein, represent the code book of channel directional information, wherein, the complex space that represents N*M, N and M represent respectively the number of antennas of subscriber equipment k and wireless receiving and dispatching station l.

Then,, in step S230, by subscriber equipment, the channel directional information after quantizing is fed back to each wireless receiving and dispatching station.

Then, in step S240, subscriber equipment receives special orthogonal reference signal or the control signal from multiple wireless receiving and dispatchings station, wherein, described special orthogonal reference signal is to adopt for the precoding of subscriber equipment structure to launch, and described control signal is the precoding for subscriber equipment structure to notification of user equipment.Then, method advances to step S250.

In step S250, special orthogonal reference signal or the control signal of subscriber equipment based on receiving carries out channel estimating, obtains combining the phase information after the quantification between the signal at wireless receiving and dispatching station of transmitting (JT) from execution.

As the example implementation of obtaining the phase information after quantification, subscriber equipment is basis first calculate from the phase place angle of carrying out between the signal at each wireless receiving and dispatching station of JT, wherein, for the fixed phase with reference to wireless receiving and dispatching station, the described arbitrary wireless receiving and dispatching station participating in execution JT wireless receiving and dispatching station that can be set to reference to wireless receiving and dispatching station.Then, subscriber equipment basis by phase place angle theta _kbe quantified as P ₁phase information after the quantification of bit wherein, represent phase place code book, wherein, because phase difference has periodically, P ₁individual quantization bit is suitable for quantizing and the basic cycle in the corresponding phase difference at any angle of certain angle.

Then,, in step S260, the phase information after quantizing is fed back to the reference wireless receiving and dispatching station in wireless receiving and dispatching station by subscriber equipment.

In one embodiment, except channel directional information and phase information, subscriber equipment also feeds back CQI.

In the time that the number K of subscriber equipment is greater than the transmitting antenna M at wireless receiving and dispatching station, wireless receiving and dispatching station is preferably selected subscriber equipment.

In order further to improve the utilization ratio of feedback resources, for subscriber equipment k, be as the criterion with following formula, point be used in to the bit number B of the channel directional information after the l feedback quantization of each wireless receiving and dispatching station _lbit number P with the phase information for to reference to after the feedback quantization of wireless receiving and dispatching station ₁:

max SIN _k

$\begin{array}{cc}s.t& \underset{l}{\mathrm{\Σ}}\end{array}{B}_l+P_1=B$

Wherein, B represents total number of bits of feedback that subscriber equipment k can be used for feeding back.

Below, taking the CoMP system that comprises three wireless receiving and dispatching stations shown in Fig. 1 as example, suppose that the wireless receiving and dispatching station of community 2, for reference to wireless receiving and dispatching station, illustrates B _land P ₁concrete method for solving.

The power P mean allocation of assumed wireless transmitting-receiving station to customer traffic, the reception signal of user k can be expressed as:

$y_k=\sqrt{\mathrm{\ρ}}(\sqrt{2}{h}_k^1{w}_k^1+h_k^2{\stackrel{\‾}{w}}_k^2)s_k+\sqrt{\mathrm{\ρ}}\underset{\stackrel{i\≠k}{i=1}}{\overset{K}{\mathrm{\Σ}}}(\sqrt{2}{h}_k^1{w}_i^1+h_k^2{\stackrel{\‾}{w}}_i^2)s_i\sqrt{\mathrm{\ρ}}\underset{j=1}{\overset{K}{\mathrm{\Σ}}}(\mathrm{\α}\sqrt{2}{h}_k^3{w}_j^3+h_k^2{\stackrel{\‾}{w}}_j^2)s_j+n_k---\left(1\right)$

In formula, s _krepresent the transmission data of user k, and E[|s _k| ²]=1, n _kfor background noise, α ∈ [0,1] represents large scale fading factor, and order:

$D_1={\left|\sqrt{2}\right|\left|h_k^1\right||{\tilde{h}}_k^1{w}_k^1+|\left|h_k^2\right|\left|{\tilde{h}}_k^2{\stackrel{\―}{w}}_k^2\right|}^2,$ $D_2=\underset{\stackrel{i\≠k}{i=1}}{\overset{K}{\mathrm{\Σ}}}{\left|\sqrt{2|}\right|\left|h_k^1\right||{\tilde{h}}_k^1{w}_i^1+|\left|h_k^2\right|\left|h_k^2{\stackrel{\‾}{w}}_i^2\right|}^2,$

$D_3=\underset{j=1}{\overset{K}{\mathrm{\Σ}}}{\left|\sqrt{2\mathrm{\α}}\right|\left|h_k^3\right||{\tilde{h}}_k^3{w}_j^3+|\left|h_k^2\right|\left|{\tilde{h}}_k^2{\stackrel{\‾}{w}}_j^2\right|}^2,$

The SINR of user k end can be expressed as:

$E\left\{{\mathrm{SINR}}_k\right\}=E\left\{\frac{D_1}{D_2+D_3+1}\right\}$ (2)

$\≥\frac{E{\{D}_1\}}{E\left\{D_2\right\}+E\left\{D_3\right\}+1}$

Article " Multi-Antenna Downlink Channels with Limited Feedback and User Selection " (referring to " Selected Areas in Communications; IEEE Journal on Volume25; Issue7, September2007Page (s): 1478-1491. ") by Taesang Yoo is known:

${\left|{\tilde{h}}_k{w}_k\right|}^2~\mathrm{Beta}(1,M-1)---\left(3\right)$

$E{\{\left|{\tilde{h}}_k{w}_k\right|}^2\}=E\{\mathrm{\β}(1,M-1)\}=1/M---\left(4\right)$

Article " Two-cell MISO Interfering Broadcast Channel with Limited Feedback::Adaptive Feedback Strategy and Multiplexing Gains. " (referring to " Communications (ICC); IEEE International Conference on, 2011 ") by Namyoon Lee is known:

Channel Modeling of the present invention is the separate and same multiple Gaussian channel distributing, but does not affect the realization of the present invention in other Channel Modeling.Calculated from Random Matrices Theory and statistical theory:

$E{\{\left|\right|h_k^l\left|\right|}^2\}=M,E\{\left|\right|h_k^l\left|\right|\}=\frac{\mathrm{\Γ}(M+1/2)}{\mathrm{\Γ}\left(M\right)}\stackrel{\mathrm{\Δ}}{=}\mathrm{\τ}---\left(7\right)$

Can obtain according to formula (3) and statistical theory calculating its average obtains

$E\left\{\right|{\tilde{h}}_k^1{w}_k^1\left|\right\}=(M-1)\·B(\frac{3}{2},M-1)\stackrel{\mathrm{\Δ}}{=}{\mathrm{\υ}}_1---\left(8\right)$

By Orthogonal Decomposition, obtain

Due to | g _kw _i| ²～Beta (1, M-2), | g _kw _i|～Kumaraswamy (2, M-2), can obtain by calculating $E\left\{\right|{\tilde{h}}_k{w}_i\left|\right\}$ The upper bound

$E\left\{\right|{\tilde{h}}_k{w}_i\left|\right\}\≤(M-2)\·B(\frac{3}{2},M-2)---\left(9\right)$

In like manner

$E\left\{\right|{\tilde{h}}_k{w}_j\left|\right\}\≤(M-2)\·B(\frac{3}{2},M-2)---\left(10\right)$

Wherein according to formula (3), to (10), formula (2) can abbreviation be:

$E\left\{{\mathrm{SINR}}_k\right\}\≥\frac{3+2\sqrt{2}{\mathrm{\τ}}^2{\mathrm{\υ}}_1^{2}E\left(\cos ({\mathrm{\θ}}_k-{\widehat{\mathrm{\θ}}}_k)\right\}}{2M\·2^{-\frac{B_1}{M-1}}+2M\·2^{-\frac{B_2}{M-1}}+{2\mathrm{\α}}^{2}M\·2^{-\frac{B_3}{M-1}}+2\sqrt{2}{\mathrm{\τ}}^2{\mathrm{\υ}}_2^2(\frac{M}{2}-1)+\sqrt{2}\mathrm{\α}{\mathrm{\τ}}^2{\mathrm{\υ}}_2^{2}M+1/\mathrm{\ρ}}---\left(11\right)$

Consider that the phase place that quantized channel directional information produces exists eye is from being uniformly distributed, therefore when with P1 bit during to θ uniform quantization, be brought in formula (11) and obtain:

$E\left\{{\mathrm{SINR}}_k\right\}\≥\frac{3+2\sqrt{2}{\mathrm{\τ}}^2{\mathrm{\υ}}_1^2\frac{2^{P_1+1}\sin \frac{\mathrm{\π}}{2^{P_1}}}{\mathrm{\π}}}{2M\·2^{-\frac{B_1}{M-1}}+2M\·2^{-\frac{B_2}{M-1}}+{2\mathrm{\α}}^{2}M\·2^{-\frac{B_3}{M-1}}+2\sqrt{2}{\mathrm{\τ}}^2{\mathrm{\υ}}_2^2(\frac{M}{2}-1)+\sqrt{2}\mathrm{\α}{\mathrm{\τ}}^2{\mathrm{\υ}}_2^{2}M+1/\mathrm{\ρ}}---\left(12\right)$

Therefore B ₁, B ₂, B ₃and P ₁allocation strategy can be expressed as follows:

$\max \frac{3+2\sqrt{2}{\mathrm{\τ}}^2{\mathrm{\υ}}_1^2\frac{2^{P_1+1}\sin \frac{\mathrm{\π}}{2^{P_1}}}{\mathrm{\π}}}{2M\·2^{-\frac{B_1}{M-1}}+2M\·2^{-\frac{B_2}{M-1}}+{2\mathrm{\α}}^{2}M\·2^{-\frac{B_3}{M-1}}+2\sqrt{2}{\mathrm{\τ}}^2{\mathrm{\υ}}_2^2(\frac{M}{2}-1)+\sqrt{2}\mathrm{\α}{\mathrm{\τ}}^2{\mathrm{\υ}}_2^{2}M+1/\mathrm{\ρ}}$

s.t.B ₁+B ₂+B ₃+P ₁＝B

(13)

Due to B ₁, B ₂, B ₃and P ₁be positive integer, therefore can obtain B by the poor search algorithm that adopts lower complexity ₁+ B ₂+ B ₃+ P ₁the value of=B constraint lower four.

Although it should be understood that and provided above B under particular condition _land P ₁concrete method for solving, those skilled in the art are easy to derive under other situations (for example, CoMP system comprises more wireless receiving and dispatchings station, or using the wireless receiving and dispatching station of community 1 as with reference to wireless receiving and dispatching station) B according to instruction herein _land P ₁concrete method for solving.

Fig. 3 shows the communication means of being carried out by the reference wireless receiving and dispatching station in mixed C oMP system being combined with above-mentioned feedback method according to the present invention.As shown in Figure 3, the method originates in step S310, wherein, and with reference to wireless receiving and dispatching station l _refreceive the channel directional information from the quantification of subscriber equipment k feedback then, method advances to step S320.

In step S320, the channel directional information after the quantification with reference to wireless receiving and dispatching station based on receiving structure precoding.

As the example implementation of structure precoding, first basis of wireless receiving and dispatching station by the channel directional information polymerization after the quantification receiving.Then, according to the transmitting pre-coding matrix of structure wireless receiving and dispatching station l.Finally, right be normalized, and obtain after normalization k row, as with reference to wireless receiving and dispatching station l _refthe precoding for user k

Then,, in step S330, receive the phase information from the quantification of subscriber equipment k feedback with reference to wireless receiving and dispatching station

Subsequently, in step S340, the phase information after the quantification with reference to wireless receiving and dispatching station based on receiving carry out precoding phase compensation.Preferably, in this step, according to carry out precoding phase compensation.

In order to realize above-mentioned feedback method, the present invention also provides a kind of subscriber equipment 400.As shown in Figure 4, subscriber equipment 400 according to the present invention comprises: signal receiving unit 410, for receiving the reference signal from multiple wireless receiving and dispatchings station, described signal receiving unit is also for receiving special orthogonal reference signal or the control signal from multiple wireless receiving and dispatchings station, described special orthogonal reference signal is to adopt the precoding for subscriber equipment of constructing to launch, the precoding for subscriber equipment that described control signal is constructed to notification of user equipment; Channel directional information is estimated and quantifying unit 430, carries out channel estimating for the reference signal that receives of basis, obtains the channel directional information after the quantification of the channel between this subscriber equipment and each wireless receiving and dispatching station; Feedback unit 440, for feeding back to each wireless receiving and dispatching station by the channel directional information after quantizing; And phase information estimates and quantifying unit 420, for carrying out channel estimating according to the special orthogonal reference signal or the control signal that receive, obtain from the phase information after the quantification between the signal at the wireless receiving and dispatching station of execution JT; Wherein, described feedback unit further feeds back to the reference wireless receiving and dispatching station in wireless receiving and dispatching station by the phase information after quantizing.

Correspondingly, the invention provides a kind of wireless receiving and dispatching station 500 being combined with subscriber equipment 400.As shown in Figure 5, comprise according to wireless receiving and dispatching of the present invention station 500: feedback information receiving element 510, for reference to wireless receiving and dispatching station l _refreceive the channel directional information from the quantification of subscriber equipment k feedback described feedback information receiving element also receives the phase information from the quantification of subscriber equipment k feedback precoding unit 520, for the channel directional information after the quantification based on receiving structure precoding; And precoding phase compensation unit 530, for the phase information after the quantification based on receiving carry out precoding phase compensation.

It should be noted in the discussion above that in above description, only in the mode of example, show technical scheme of the present invention, but be not intended that the invention be limited to above-mentioned steps and cellular construction.Under possible situation, can as required step and cellular construction be adjusted and be accepted or rejected.Therefore, the necessary element of overall invention thought of the present invention is not implemented in some step and unit.Therefore, technical characterictic essential to the invention is only limited to the minimum requirements that can realize overall invention thought of the present invention, and is not subject to the restriction of above instantiation.

So far invention has been described in conjunction with the preferred embodiments.Should be appreciated that, those skilled in the art without departing from the spirit and scope of the present invention, can carry out various other change, replacement and interpolations.Therefore, scope of the present invention is not limited to above-mentioned specific embodiment, and should be limited by claims.

Claims (12)

1. a feedback method of being carried out by the subscriber equipment mixing in cooperative multipoint transmission (CoMP) system, comprises the following steps:

I) receive the reference signal from multiple wireless receiving and dispatchings station;

Ii) carry out channel estimating based on the reference signal receiving, obtain the channel directional information after the quantification of the channel between this subscriber equipment and each wireless receiving and dispatching station;

Iii) the channel directional information after quantizing is fed back to each wireless receiving and dispatching station;

Iv) receive special orthogonal reference signal or the control signal from multiple wireless receiving and dispatchings station, described special orthogonal reference signal is to adopt for the precoding of subscriber equipment structure to launch, and described control signal is the precoding for subscriber equipment structure to notification of user equipment;

V) the special orthogonal reference signal based on receiving or control signal carry out channel estimating, obtain combining the phase information after the quantification between the signal at wireless receiving and dispatching station of transmitting (JT) from execution; And

Vi) phase information after quantizing is fed back to the reference wireless receiving and dispatching station in wireless receiving and dispatching station.

2. method according to claim 1, wherein, for subscriber equipment k, is as the criterion with following formula, point is used in to the bit number B of the channel directional information after the l feedback quantization of each wireless receiving and dispatching station _lbit number P with the phase information for to reference to after the feedback quantization of wireless receiving and dispatching station ₁:

max SINR _k

$\begin{array}{cc}s.t& \underset{l}{\mathrm{\Σ}}\end{array}{B}_l+P_1=B$

Wherein, B represents total number of bits of feedback that subscriber equipment k can be used for feeding back.

3. method according to claim 1 and 2, wherein, described step I i) further comprises:

Calculate the channel information between each wireless receiving and dispatching station l and subscriber equipment k

According to calculate normalized channel directional information; And

According to by normalized channel directional information be quantified as B _lchannel directional information after the quantification of bit wherein, represent the code book of channel directional information, wherein, the complex space that represents N*M, N and M represent respectively the number of antennas of subscriber equipment k and wireless receiving and dispatching station l.

4. method according to claim 1 and 2, is characterized in that, described step v) further comprises:

According to calculate from the phase place angle of carrying out between the signal at each wireless receiving and dispatching station of JT, wherein, for the fixed phase with reference to wireless receiving and dispatching station; And

According to by phase place angle theta _kbe quantified as P ₁phase information after the quantification of bit wherein, represent phase place code book, wherein,

5. a communication means of being carried out by the reference wireless receiving and dispatching station of mixing in cooperative multicast system, comprising:

I) with reference to wireless receiving and dispatching station l _refreceive the channel directional information from the quantification of subscriber equipment k feedback

Ii) the channel directional information after the quantification based on receiving structure precoding;

Iii) receive the phase information from the quantification of subscriber equipment k feedback and

Iv) phase information after the quantification based on receiving carry out precoding phase compensation.

6. method according to claim 5, wherein, described step I i) further comprises:

According to by the channel directional information polymerization after the quantification receiving;

According to the transmitting pre-coding matrix of structure wireless receiving and dispatching station l; And

Right be normalized, and obtain after normalization k row, as with reference to wireless receiving and dispatching station l _refthe precoding for user k

7. method according to claim 6, wherein, described step I v) in, according to carry out precoding phase compensation.

8. a subscriber equipment, comprising:

Signal receiving unit, for receiving the reference signal from multiple wireless receiving and dispatchings station, described signal receiving unit is also for receiving special orthogonal reference signal or the control signal from multiple wireless receiving and dispatchings station, described special orthogonal reference signal is to adopt the precoding for subscriber equipment of constructing to launch, the precoding for subscriber equipment that described control signal is constructed to notification of user equipment;

Channel directional information estimates and quantifying unit, for carrying out channel estimating according to the reference signal that receives, obtains the channel directional information after the quantification of the channel between this subscriber equipment and each wireless receiving and dispatching station;

Feedback unit, for feeding back to each wireless receiving and dispatching station by the channel directional information after quantizing; And

Phase information estimates and quantifying unit, for carrying out channel estimating according to the special orthogonal reference signal or the control signal that receive, obtains from the phase information after the quantification of carrying out between the signal at wireless receiving and dispatching station of JT;

Wherein, described feedback unit further feeds back to the reference wireless receiving and dispatching station in wireless receiving and dispatching station by the phase information after quantizing.

9. subscriber equipment according to claim 8, wherein, described channel directional information is estimated and quantifying unit comprises:

Channel information calculating part, for calculating the channel information between each wireless receiving and dispatching station l and subscriber equipment k $h_k^l;$

Normalization channel directional information calculating part, for basis calculate normalized channel directional information; And

Quantized channel directional information calculating part, for basis by normalized channel directional information be quantified as B _lchannel directional information after the quantification of bit wherein, represent the code book of channel directional information, wherein, the complex space that represents N*M, N and M represent respectively the number of antennas of subscriber equipment k and wireless receiving and dispatching station l.

10. subscriber equipment according to claim 8, wherein, described phase information is estimated and quantifying unit comprises:

Phase place angle calculating part, for basis ${\mathrm{\θ}}_k=\underset{l_{\mathrm{JT}}\≠l_{\mathrm{ref}}}{\mathrm{\Σ}}\∠\left(h_k^{l_{\mathrm{JT}}}{w}_k^{l_{\mathrm{JT}}}\right)-\∠\left(h_k^{l_{\mathrm{ref}}}{w}_k^{l_{\mathrm{ref}}}\right),$ Calculate from the phase place angle of carrying out between the signal at each wireless receiving and dispatching station of JT, wherein, for the fixed phase with reference to wireless receiving and dispatching station; And

The poor information calculating part of Quantization phase, for basis by phase place angle theta _kbe quantified as P ₁phase information after the quantification of bit wherein, represent phase place code book, wherein,

11. 1 kinds of wireless receiving and dispatching stations, comprising:

Feedback information receiving element, for reference to wireless receiving and dispatching station l _refreceive the channel directional information from the quantification of subscriber equipment k feedback described feedback information receiving element also receives the phase information from the quantification of subscriber equipment k feedback

Precoding unit, for the channel directional information after the quantification based on receiving structure precoding; And

Precoding phase compensation unit, for the phase information after the quantification based on receiving carry out precoding phase compensation.

12. wireless receiving and dispatching according to claim 11 stations, wherein, described precoding unit comprises:

Channel directional information converging portion, for basis by the channel directional information polymerization after the quantification receiving;

Pre-coding matrix structure portion, for basis the transmitting pre-coding matrix of structure wireless receiving and dispatching station l; And

Precoding forming portion, for right be normalized, and obtain after normalization k row, as with reference to wireless receiving and dispatching station l _refthe precoding for user k