CN102571172A - User scheduling method and equipment in MIMO wireless communication system - Google Patents

Abstract

The invention relates to a user scheduling method and equipment in an MIMO (Multiple Input Multiple Output) wireless communication system. All user equipment select the respective channel vectors from a codebook according to the minimum chordal distance rule, the SINR (Signal to Interference Plus Noise Ratio) value of a channel between each user equipment and a base station of which the user equipment belongs, then the indexes and the SINR values of the channel vectors of all the user equipment are sent to network equipment, the network equipment selects the user equipment according to channel-related information fed back by all the user equipment to enable the channel response matrix of each selected user equipment and the combined channel response matrix of other selected user equipment to meet the predetermined orthogonality condition, and the codebook reconstructs the corresponding pre-encodingmatrix in a centralized manner according to the respective codebook indexes of all the selected user equipment. The invention has the advantages that the channel response direction vectors of users are quantified by adopting the minimum chordal distance rule, and the users are scheduled by adopting the chordal distance, so that a good balance is stricken for reducing both the common-channel interference (CCI) and multi-user diversity gain.

Description

In mimo wireless communication system, carry out the method and apparatus of user's scheduling

Technical field

The present invention relates to the mimo wireless communication field, relate in particular to a kind of method and apparatus that in mimo wireless communication system, carries out user's scheduling.

Background technology

In the past few years, multi-user's multiple-input and multiple-output (MIMO) technology has caused the extensive concern of industry, and this technology can utilize that the diversity gain between the multi-user improves power system capacity in the transmission course.But in multiuser MIMO (MU-MIMO) system, common-channel interference (CCI) is to hinder the big factor that systematic function further promotes.In order to eliminate common-channel interference (CCI), suitable precoding technique emerges gradually.Yet precoding technique is relevant with user's scheduling scheme usually, and good scheduling scheme is the performance of elevator system further.So user's scheduling scheme also is main points that need consideration in improving the process of systematic function.In addition, multiuser MIMO specification requirement base station end is carried out user's traffic control under the situation of known mobile terminal channel condition information (CSI), construct precoder then.Under time division duplex (TDD) pattern, ideal communication channel state information (CSI) can obtain.Yet, under mode of frequency division duplexing, unlikely obtaining desirable channel condition information (CSI), this will make system choose the subscriber equipment of compliance with system performance requirement to become difficult.Thereby multi-user MIMO system is under limited feedback information, and how appropriate selection transmission user will be an emphasis and difficult point.

The preferred plan that addresses the above problem at present is following:

Each subscriber equipment uses the code book of M dimension normalized vector to come the quantized channel direction, and feeds back to corresponding code book index (size of the code book collection of employing is N=2B), and the Signal to Interference plus Noise Ratio (SINR) estimated to base station (BS).The subscriber equipment that will be transmitted is selected according to the feedback information of all subscriber equipmenies in the base station, and the design precoder, and Here it is quantizes the close-to zero beam excipient technology (ZFBF) of (CVQ) based on channel vector.

The shortcoming of this scheme is: the base station only after subscriber equipment finally is scheduled completion, could be designed exactly and compel zero precoder; And the Signal to Interference plus Noise Ratio of each subscriber equipment feedback is an estimated value, and this has just caused selected user equipment not necessarily optimum, so, will cause systematic function to descend.

Summary of the invention

The purpose of this invention is to provide a kind of method and apparatus that in mimo wireless communication system, carries out user's scheduling.

According to an aspect of the present invention, a kind of method that in the network equipment based on the wireless communication system of MIMO, is used to carry out user's scheduling is provided, wherein, each subscriber equipment comprises the code book collection identical with the network equipment, and wherein, this method may further comprise the steps:

-receive feedback information from N subscriber equipment, be used to characterize the code book index and estimation SINR information of channel response vector separately comprising a said N subscriber equipment;

Wherein, said method is further comprising the steps of:

A. come to select one by one subscriber equipment according to the channel related information of subscriber equipment feedback; So that the channel response matrix of selected each subscriber equipment and other have selected the combined channel response matrix of subscriber equipment to satisfy predetermined orthogonality condition, and concentrate the corresponding pre-coding matrix of reconstruct by said code book according to selected each subscriber equipment code book index separately that goes out.

According to another aspect of the present invention, a kind of method that in the subscriber equipment based on the wireless communication system of MIMO, is used to carry out user's scheduling is provided also, wherein, subscriber equipment comprises the code book collection identical with the network equipment, and wherein, this method comprises:

-according to smallest chord apart from rule, by selecting corresponding channel vector in the said code book;

Wherein, said method also comprises:

The SINR value of the channel between-estimation and the affiliated base station;

Wherein, further comprising the steps of:

-code book index of said channel vector correspondence and estimated SINR value are sent to the network equipment.

According to a further aspect of the invention, a kind of network equipment that in the wireless communication system based on MIMO, is used to carry out user's scheduling is provided also, wherein, each subscriber equipment comprises the code book collection identical with the network equipment, and this network equipment comprises:

Receiving system is used to receive the feedback information from N subscriber equipment, comprising the said N subscriber equipment code book index and estimation SINR information that are used to characterize the channel response vector separately;

User dispatching device; Be used for to select one by one subscriber equipment, be scheduled to orthogonality condition so that the channel response matrix of selected each subscriber equipment has selected the combined channel response matrix of subscriber equipment to satisfy with other according to the channel related information of said subscriber equipment feedback;

Reconfiguration device is used for the code book index based on selected each subscriber equipment that goes out, and concentrates the corresponding pre-coding matrix of reconstruct by said code book.

According to a further aspect of the invention, a kind of subscriber equipment that in the wireless communication system based on MIMO, is used to carry out user's scheduling is provided also, wherein, subscriber equipment comprises the code book collection identical with the network equipment, and wherein, this subscriber equipment comprises:

The 3rd choice device is used for according to smallest chord apart from rule, by selecting corresponding channel vector in the said code book;

Wherein, said subscriber equipment also comprises:

Estimation unit, be used to estimate and affiliated base station between the SINR value of channel;

Wherein, also comprise:

Dispensing device is used for code book index that said channel vector is corresponding and estimated SINR value and sends to the network equipment.

Compared with prior art; The present invention has the following advantages: adopt smallest chord to quantize user's channel response direction vector apart from rule; And adopt string apart from coming dispatched users, can effectively obtain well-balanced between minimizing common-channel interference (CCI) and the multi-user diversity gain.

Description of drawings

Through reading the detailed description of doing with reference to following accompanying drawing that non-limiting example is done, it is more obvious that other features, objects and advantages of the present invention will become:

Fig. 1 is the system topological figure that is used to carry out user's scheduling of the present invention;

Fig. 2 is the method flow diagram that is used to carry out user's scheduling of one aspect of the invention;

Fig. 3 is the method flow diagram that is used to carry out user's scheduling of another aspect of the present invention;

Fig. 4 is the system schematic that is used to carry out user's scheduling of one aspect of the invention;

Fig. 5 is the system schematic that is used to carry out user's scheduling of another aspect of the present invention;

Fig. 6 is for the present invention with based on the performance comparison diagram of the ZFBF scheme of CVQ.

Same or analogous Reference numeral is represented same or analogous parts in the accompanying drawing.

Embodiment

Below in conjunction with accompanying drawing the present invention is described in further detail.

Fig. 1 shows the system topological figure that the present invention is used to carry out user's scheduling.Said system is the wireless communication system based on MIMO, and it comprises: subscriber equipment 11, subscriber equipment 12 ... Subscriber equipment 1N, and the network equipment 2; Subscriber equipment 11, subscriber equipment 12 ... In the subscriber equipment 1N and the network equipment 2; All preserve identical code book

wherein; The network equipment 2 can be any electronic equipment that can carry out user's scheduling; It includes but not limited to: 1) base station; For example, BS, e-Node B etc.; 2) network controller etc.The said network equipment 2 can be directly or indirectly and each communications of user equipment; For example; If the said network equipment 2 is the base station; Then it can directly be communicated by letter with wireless mode with each subscriber equipment, and if the said network equipment 2 is a network controller, then it can pass through the base station and communicating by letter of each subscriber equipment etc. that are connected.And each subscriber equipment can be any electronic equipment that can directly or indirectly communicate by letter with the network equipment 2 with wireless mode, includes but not limited to: mobile phone, PDA etc.

In addition; As a kind of optimal way; Each subscriber equipment in this wireless communication system has only an antenna, and the base station has M root antenna, adopts mode of frequency division duplexing (frequency-division duplexing mode between each subscriber equipment and the base station; FDD mode) receive and send messages, K subscriber equipment can be dispatched in the base station at every turn.But the pattern that it should be appreciated by those skilled in the art that each subscriber equipment and base station transceiver information is not that the above exceeds.

Fig. 2 shows the flow chart that one aspect of the invention is used to carry out the method for user's scheduling.Wherein, be that the base station is that example is described with the network equipment 2.And; For simplicity of illustration; Be that example is described only among the figure, but it should be appreciated by those skilled in the art, in fact with the communication interaction between the subscriber equipment 11 and the network equipment 2; Subscriber equipment 12 ... Subscriber equipment 1N also communicating alternately with the network equipment 2, details at this no longer one by one.

Concrete, in step S1, subscriber equipment 11 receives transmitting from the network equipment 2.For example, subscriber equipment 11 receives transmit for:

Wherein, the mid portion on equal sign the right is the common-channel interference (CCI) that other subscriber equipment produces in the formula, and last part is represented noise, p _iRepresent i independent data stream s _iSignal transmission power, W=[t ₁t ₂T _K] be pre-coding matrix, K≤M.And if subscriber equipment 11 is for compeling zero receiver, then receive transmit for:

G ₁＝(h ₁t ₁) ^H((h ₁W)(h ₁W) ^H) ^-1。

Then, in step S2, subscriber equipment 11 according to transmitting of receiving and smallest chord apart from rule, by selecting corresponding channel vector in the said code book.For example, subscriber equipment 11 is h according to the channel matrix between the signal estimation that receives self and the network equipment 2 ₁, thus, according to

Can obtain the channel vector of unit normalized Subsequently, subscriber equipment 11 again according to smallest chord apart from rule, to the channel vector of unit normalized

Quantize, just basis:

${\hat{h}}_1=c_n,n=\arg \underset{i=1,...,2^B}{\min }{d}_{\mathrm{chord}}({\tilde{h}}_1,c_i)=\arg \underset{i=1,...,2^B}{\min }\frac{1}{\sqrt{2}}{\left|\right|{\tilde{h}}_1^H{\tilde{h}}_1-c_i^H{c}_i\left|\right|}_F$

In code book, select a suitable quantized channel vector

In addition, as a kind of optimal way, because to matrix h ₁Do singular value decomposition one time, that is:

λ wherein ₁Expression h ₁Singular value, can get by matrix theorem,

And then subscriber equipment 11 can basis after estimating channel matrix:

Adopt the channel vector that obtains unit normalized Again it is carried out vector quantization subsequently.

Because those skilled in the art know for the technology that the subscriber equipment information how basis receives estimates channel information, so be not described in detail in this.

Then, in step S3, subscriber equipment 11 again according to said transmit estimate and affiliated base station between the SINR value of channel.For example, subscriber equipment 11 is according to the G that transmits that is received ₁The SINR value of estimating is:

${\mathrm{SINR}}_1=\frac{{\left|{\tilde{G}}_1{h}_1{t}_1\right|}^2}{\underset{i=2}{\overset{K_T}{\mathrm{\Σ}}}{\left|{\tilde{G}}_1{h}_1{t}_i\right|}^2+\frac{1}{\mathrm{\β}}},$

Wherein,

β=P/K σ ²,

σ ²Be noise variance.

Then, in step S4, code book index that subscriber equipment 11 is corresponding with said channel vector and estimated SINR value send to the network equipment.For example, subscriber equipment 11 is with channel vector

Corresponding code book index and estimated SINR ₁Send to the network equipment 2.

Then, in step S5, the feedback information that the network equipment 2 receives from N subscriber equipment is used to characterize the code book index of channel response vector separately and estimates SINR information comprising a said N subscriber equipment.For example, the network equipment 2 receive from subscriber equipment 11, subscriber equipment 12 ... Subscriber equipment 1N channel vector separately

Corresponding code book index and estimated separately SINR ₁, SINR ₂... SINR _NWherein, subscriber equipment 12 ... Subscriber equipment 1N obtains channel vector separately

Corresponding code book index and SINR separately ₂... SINR _NMethod identical with subscriber equipment 11; Be that each subscriber equipment is transmitted according to what receive separately; Estimate earlier separately and the channel matrix between the network equipment 2; Obtain the channel vector of unit normalized separately subsequently again according to channel matrix, quantize based on the channel vector of code book again, can obtain channel vector separately thus unit normalized

Corresponding code book index, and each subscriber equipment estimates that SINR separately is also identical with subscriber equipment 11, is not described in detail in this.

Then; In step S6; The network equipment 2 selects one by one subscriber equipment according to the channel related information of each subscriber equipment feedback; So that the channel response matrix of selected each subscriber equipment and other have selected the combined channel response matrix of subscriber equipment to satisfy predetermined orthogonality condition, and concentrate the corresponding pre-coding matrix of reconstruct by said code book according to selected each subscriber equipment code book index separately that goes out.For example, the network equipment 2 according to subscriber equipment 11, subscriber equipment 12 ... The channel vector separately of subscriber equipment 1N

Corresponding code book index and estimated separately SINR ₁, SINR ₂... SINR _N, come to select one by one subscriber equipment, so that the channel response matrix separately of the subscriber equipment of selecting and other have selected the combined channel response matrix of subscriber equipment to satisfy predetermined orthogonality condition, and based on selected K the subscriber equipment channel vector separately that goes out

Form pre-coding matrix based on close-to zero beam excipient (ZFBF) technology, thereby the information of K subscriber equipment selecting is carried out precoding processing, and then formed transmitting launched through antenna.Known by those skilled in the art owing to form the process that transmits, so be not described in detail in this.

Need to prove, it should be appreciated by those skilled in the art that the order of above-mentioned each step is not to exceed with said, in fact, step S3 also can carry out before the step S2 etc.

Fig. 3 shows the flow chart that one aspect of the invention is used to carry out the method for user's scheduling.

Concrete, step S1 to step S5 detailing among the described embodiment with reference to Fig. 2, comprise by reference at this, repeat no more.

Then, in step S6 ', the network equipment 2 selects to estimate that the maximum subscriber equipment of SINR is as first subscriber equipment.For example, the subscriber equipment 11 that receives of the network equipment 2, subscriber equipment 12 ... The SINR of subscriber equipment 1N ₁, SINR ₂... SINR _NIn, SINR ₁Maximum, thus, the network equipment 2 with subscriber equipment 11 as first subscriber equipment.

Then, in step S7 ', the network equipment 2 is concentrated the reconstruct precoding vectors based on the code book index of said first subscriber equipment feedback by said code book.For example; If first subscriber equipment that the network equipment is selected is a subscriber equipment 11; Then the network equipment 2 is based on the code book index of subscriber equipment 11 feedbacks; The channel vector

that concentrate to obtain subscriber equipment 11 by said code book thus, the precoding vectors of the network equipment 2 reconstruct is:

Then; In step S8 '; The network equipment 2 is selected next subscriber equipment in non-selected subscriber equipment; And come the corresponding precoding vectors of reconstruct based on said code book index, so that the channel response matrix of said next subscriber equipment and other have selected the combined channel response matrix of subscriber equipment to satisfy predetermined orthogonality condition.Wherein, Said predetermined orthogonality condition includes but not limited to: the channel response matrix of selected user equipment and other have been selected for use between the combined channel response matrix of family equipment and have been satisfied semi-orthogonal property condition, and the estimation SINR value second predetermined condition of selected user equipment.

More in specific words, said predetermined orthogonality condition satisfies following formula:

$T_{i+1}=\{k\∈T_i,k\≠\mathrm{\π}\left(i\right)|\frac{d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}=\frac{\frac{1}{\sqrt{2}}{\left|\right|{\hat{h}}_k^H{\hat{h}}_k-{\tilde{g}}_i^H{\tilde{g}}_i\left|\right|}_F}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}>\mathrm{\α}\}$

i←i+1

Wherein, the α value changes in 0.8-0.99 value interval along with the increase (10-10,000) of scheduled user's number of devices K.Said second predetermined condition includes but not limited to: the estimation SINR value of selected user equipment is a maximum etc.

For example, the network equipment 2 selections first are following to the process synthesis of K subscriber equipment:

At first, at step I, the network equipment 2 initialization T ₁=1 ..., N}, i=1,

Then, in Step II, the network equipment 2 is each subscriber equipment k ∈ T _iCalculate,

$g_k={\hat{h}}_k-{\hat{h}}_k\underset{j=1}{\overset{i-1}{\mathrm{\Σ}}}{\tilde{g}}_j^H{\tilde{g}}_j$

And normalized vector

Then, at Step II I: the network equipment is selected i subscriber equipment according to following mode:

$\mathrm{\π}\left(i\right)=\arg \underset{k\∈T_i}{\max }{\mathrm{SINR}}_k$

S←S+{π(i)}

h _i＝h _π(i)

g _i＝g _π(i)

T _i＝T _i-{π(i)}

Then, at step IV: if | S|＜K, then:

$T_{i+1}=\{k\∈T_i,k\≠\mathrm{\π}\left(i\right)|\frac{d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}=\frac{\frac{1}{\sqrt{2}}{\left|\right|{\hat{h}}_k^H{\hat{h}}_k-{\tilde{g}}_i^H{\tilde{g}}_i\left|\right|}_F}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}>\mathrm{\α}\}$

i←i+1

Return Step II then, when | during S|=K, the network equipment 2 stops to select subscriber equipment.

Obviously, therefore first subscriber equipment that the network equipment is selected is the pairing subscriber equipment of SINR the maximum, then based on the code book index of first subscriber equipment feedback, concentrates the reconstruct precoding vectors by said code book

Again based on precoding vectors

Make up the orthogonal basis vector

And then acquisition candidate user devices collection T _I+1, this candidate user devices collection T _I+1In each subscriber equipment and the orthogonal basis vector that made up Had semi-orthogonal property, then, concentrated in candidate user devices and select the pairing subscriber equipment of SINR the maximum, so, constantly repeated, the network equipment 2 can be selected K subscriber equipment.For example; The K that the network equipment 2 an is selected subscriber equipment be respectively subscriber equipment 11, subscriber equipment 12 ... Subscriber equipment 1K; And then, according to the pre-coding matrix of channel vector

network equipment 2 reconstruct of those subscriber equipmenies be:

$W=\left[\begin{array}{cccc}{t}_1& t_2& ...& t_{s_K}\end{array}\right]=\left[\begin{array}{cccc}{\hat{h}}_1^H& {\hat{h}}_2^H& ...& {\hat{h}}_{s_K}^H\end{array}\right].$

Fig. 4 shows the sketch map that one aspect of the invention is used to carry out the system of user's scheduling.Wherein, subscriber equipment 11 comprises: the 3rd choice device 111, estimation unit 112, and dispensing device 113; Subscriber equipment 12 comprises: the 3rd choice device 121, estimation unit 122, and dispensing device 123 (figure does not show); Subscriber equipment 1N comprises: the 3rd choice device 1N1, estimation unit 1N2, and dispensing device 1N3; The network equipment 2 comprises: receiving system 21, user dispatching device 22 and reconfiguration device 23.

Concrete, subscriber equipment 11, subscriber equipment 12 ... Subscriber equipment 1N receives transmitting from the network equipment 2 separately.For example, k subscriber equipment receives transmit for:

Wherein, the mid portion on equal sign the right is the common-channel interference (CCI) that other subscriber equipment produces in the formula, and last part is represented noise, p _iRepresent i independent data stream s _iSignal transmission power, w=[t ₁t ₂T _K] be pre-coding matrix, K≤M.And if each subscriber equipment is for compeling zero receiver, then k subscriber equipment reception transmit for:

G _k＝(h _kt _k) ^H((h _kW)(h _kW) ^H) ^-1。

Then, the 3rd choice device 111, the 3rd choice device 121 ... The 3rd choice device 1N1, separately according to transmitting of receiving and smallest chord apart from rule, by selecting corresponding channel vector in the said code book.For example, the 3rd choice device 111 is h according to the channel matrix between the signal estimation that receives self and the network equipment 2 ₁, thus, according to

Can obtain the channel vector of unit normalized

Subsequently, the 3rd choice device 111 again according to smallest chord apart from rule, to the channel vector of unit normalized Quantize, just basis:

${\hat{h}}_1=c_n,n=\arg \underset{i=1,...,2^B}{\min }{d}_{\mathrm{chord}}({\tilde{h}}_1,c_i)=\arg \underset{i=1,...,2^B}{\min }\frac{1}{\sqrt{2}}{\left|\right|{\tilde{h}}_1^H{\tilde{h}}_1-c_i^H{c}_i\left|\right|}_F$

In code book, select a suitable quantized channel vector

In addition, as a kind of optimal way, because to matrix h ₁Do singular value decomposition one time, that is:

λ wherein ₁Expression h ₁Singular value, can get by matrix theorem,

And then the 3rd choice device 111 can basis after estimating channel matrix:

Obtain the channel vector of unit normalized

Again it is carried out vector quantization subsequently.

Based on the identical mode of above-mentioned the 3rd choice device 111; The 3rd choice device 121 ... Select corresponding channel vector in each free said code book of the 3rd choice device 1N1, for example be respectively:

Because those skilled in the art know for the technology that each subscriber equipment information how basis receives estimates channel information, so be not described in detail in this.

Then, estimation unit 112, estimation unit 122 ... Estimation unit 1N2 separately again according to said transmit estimate and affiliated base station between the SINR value of channel.For example, estimation unit 112 is according to the G that transmits that is received ₁The SINR value of estimating is:

${\mathrm{SINR}}_1=\frac{{\left|{\tilde{G}}_1{h}_1{t}_1\right|}^2}{\underset{i=2}{\overset{K_T}{\mathrm{\Σ}}}{\left|{\tilde{G}}_1{h}_1{t}_i\right|}^2+\frac{1}{\mathrm{\β}}},$

Wherein,

β=P/K σ ²,

σ ²Be noise variance.

Based on the identical mode of above-mentioned estimation unit 112, estimation unit 122 ... The SINR value that estimation unit 1N2 estimates separately for example is respectively: SINR ₂... SINR _N

Then, dispensing device 113, dispensing device 123 ... Dispensing device 1N3 incites somebody to action the code book index of channel vector correspondence separately separately and estimated SINR value sends to the network equipment 2.For example, dispensing device 113 is with channel vector Corresponding code book index and estimated SINR ₁Send to the network equipment 2; Dispensing device 123 is with channel vector

Corresponding code book index and estimated SINR ₂Send to the network equipment 2; Dispensing device 1N3 is with channel vector

Corresponding code book index and estimated SINR _NSend to the network equipment 2;

Then, the feedback information that the network equipment 2 receives from N subscriber equipment is used to characterize the code book index of channel response vector separately and estimates SINR information comprising a said N subscriber equipment.For example, the network equipment 2 receive from subscriber equipment 11, subscriber equipment 12 ... Subscriber equipment 1N channel vector separately

Corresponding code book index and estimated separately SINR ₁, SINR ₂... SINR _N

Then; User dispatching device 22 selects one by one subscriber equipment according to the channel related information of said N subscriber equipment feedback; So that the channel response matrix of selected each subscriber equipment and other have selected the combined channel response matrix of subscriber equipment to satisfy predetermined orthogonality condition, and concentrate the corresponding pre-coding matrix of reconstruct by said code book according to selected each subscriber equipment code book index separately that goes out.For example, user dispatching device 22 according to subscriber equipment 11, subscriber equipment 12 ... The channel vector separately of subscriber equipment 1N

Corresponding code book index and estimated separately SINR ₁, SINR ₂... SINR _N, come to select one by one subscriber equipment, so that the channel response matrix separately of the K that a selects subscriber equipment satisfies predetermined orthogonality condition, and based on selected K the subscriber equipment channel vector separately that goes out

Form pre-coding matrix based on close-to zero beam excipient (ZFBF) technology, thereby the information of K subscriber equipment selecting is carried out precoding processing, and then formed transmitting launched through antenna.Known by those skilled in the art owing to form the process that transmits, so be not described in detail in this.

Need to prove; It should be appreciated by those skilled in the art that the job order of above-mentioned each device is not to exceed with said, in fact; Also can, each estimation unit in code book, select corresponding channel vector etc. by each the 3rd choice device again after having estimated SINR separately.

Fig. 5 shows the sketch map that another aspect of the present invention is used to carry out the system of user's scheduling.Wherein, subscriber equipment 11 comprises: the 3rd choice device 111, estimation unit 112, and dispensing device 113; Subscriber equipment 12 comprises: the 3rd choice device 121, estimation unit 122, and dispensing device 123 (figure does not show); Subscriber equipment 1N comprises: the 3rd choice device 1N1, estimation unit 1N2, and dispensing device 1N3; The network equipment 2 comprises: receiving system 21, user dispatching device 22 and reconfiguration device 23.Wherein, user dispatching device 22 also comprises: first choice device 221 and second choice device 222.

Concrete; The 3rd choice device 111, the 3rd choice device 121 ... The 3rd choice device 1N1, estimation unit 112, estimation unit 122 ... Estimation unit 1N2, dispensing device 113, dispensing device 123 ... Dispensing device 1N3, and receiving system 21 detailing among the described embodiment with reference to Fig. 4; Comprise by reference at this, repeat no more.

Then, first choice device 221 selects to estimate that the maximum subscriber equipment of SINR is as first subscriber equipment.For example, the subscriber equipment 11 that receives of receiving system 21, subscriber equipment 12 ... The SINR of subscriber equipment 1N ₁, SINR ₂... SINR _NIn, SINR ₁Maximum, thus, first choice device 221 with subscriber equipment 11 as first subscriber equipment.

Then, first choice device 221 is concentrated the reconstruct precoding vectors based on the code book index of said first subscriber equipment feedback by said code book.For example; If first subscriber equipment that first choice device 221 is selected is a subscriber equipment 11; Then first choice device 221 is based on the code book index of subscriber equipment 11 feedbacks; The channel vector

that concentrate to obtain subscriber equipment 11 by said code book thus, the precoding vectors of first choice device, 221 reconstruct is:

Then; Second choice device 222 is selected next subscriber equipment in non-selected subscriber equipment; And come the corresponding precoding vectors of reconstruct based on said code book index, so that the channel response matrix of said next subscriber equipment and other have selected the combined channel response matrix of subscriber equipment to satisfy predetermined orthogonality condition.Wherein, Said predetermined orthogonality condition includes but not limited to: the channel response matrix of selected user equipment and other have been selected for use between the combined channel response matrix of family equipment and have been satisfied semi-orthogonal property condition, and the estimation SINR value second predetermined condition of selected user equipment.

More in specific words, said predetermined orthogonality condition satisfies following formula:

$T_{i+1}=\{k\∈T_i,k\≠\mathrm{\π}\left(i\right)|\frac{d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}=\frac{\frac{1}{\sqrt{2}}{\left|\right|{\hat{h}}_k^H{\hat{h}}_k-{\tilde{g}}_i^H{\tilde{g}}_i\left|\right|}_F}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}>\mathrm{\α}\}$

i←i+1

Wherein, the α value changes in 0.8-0.99 value interval along with the increase (10-10,000) of scheduled user's number of devices K.Said second predetermined condition includes but not limited to: the estimation SINR value of selected user equipment is a maximum etc.

For example, first choice device 221 and 222 selections first of second choice device are following to the process synthesis of K subscriber equipment:

At first, at step I, initialization T ₁=1 ..., N}, i=1,

Then, in Step II, be each subscriber equipment k ∈ T _iCalculate,

$g_k={\hat{h}}_k-{\hat{h}}_k\underset{j=1}{\overset{i-1}{\mathrm{\Σ}}}{\tilde{g}}_j^H{\tilde{g}}_j$

And normalized vector

Then, at Step II I: select i subscriber equipment following:

$\mathrm{\π}\left(i\right)=\arg \underset{k\∈T_i}{\max }{\mathrm{SINR}}_k$

S←S+{π(i)}

h _i＝h _π(i)

g _i＝g _π(i)

T _i＝T _i-{π(i)}

Then, at step IV: if | S|＜K, then:

$T_{i+1}=\{k\∈T_i,k\≠\mathrm{\π}\left(i\right)|\frac{d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}=\frac{\frac{1}{\sqrt{2}}{\left|\right|{\hat{h}}_k^H{\hat{h}}_k-{\tilde{g}}_i^H{\tilde{g}}_i\left|\right|}_F}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}>\mathrm{\α}\}$

i→i+1

Return Step II then, when | during S|=K, stop to select subscriber equipment.

Obviously, therefore first subscriber equipment that first choice device 221 is selected is the pairing subscriber equipment of SINR the maximum, and the code book index that then feeds back based on first subscriber equipment is concentrated the reconstruct precoding vectors by said code book

Again based on precoding vectors

Make up the orthogonal basis vector

And then acquisition candidate user devices collection T _I+1, this candidate user devices collection T _I+1In each subscriber equipment and the orthogonal basis vector that made up Had semi-orthogonal property, then, second choice device 222 is concentrated in candidate user devices and is selected the pairing subscriber equipment of SINR the maximum, so, constantly repeats, and the network equipment 2 can be selected K subscriber equipment.For example; K the subscriber equipment that first choice device 221 and second choice device 222 are selected be respectively subscriber equipment 11, subscriber equipment 12 ... Subscriber equipment 1K; And then, according to the pre-coding matrix of channel vector

reconfiguration device 23 reconstruct of those subscriber equipmenies be:

$W=\left[\begin{array}{cccc}{t}_1& t_2& ...& t_{s_K}\end{array}\right]=\left[\begin{array}{cccc}{\hat{h}}_1^H& {\hat{h}}_2^H& ...& {\hat{h}}_{s_K}^H\end{array}\right].$

Below will superior function of the present invention be described with simulation result.

In emulation, use single footpath rayleigh fading channel, 4 arrangement of antennas are adopted in the base station, and each subscriber equipment adopts the configuration of single antenna; Adopt the random vector of constant power distribution, 4 bits to quantize (RVQ) code book; Always have 20 candidate user, the base station is finally selected 2 users and is transmitted.Signal to noise ratio (snr) equals 0dB or 5dB in emulation.Fig. 6 showed the present invention and quantized the close-to zero beam excipient (ZFBF) of (CVQ) based on channel vector, under different SNR, and the comparison of the total speed of user.Under the identical feedback condition of estimation Signal to Interference plus Noise Ratio (SINR) that has only a scalar to represent and code book index, can see the present invention, the close-to zero beam excipient (ZFBF) with respect to quantize (CVQ) based on channel vector has tangible performance improvement.Reason is that the present invention has adopted the minimum chordal distance rule to quantize user's channel response direction vector, and adopts string apart from coming dispatched users, is effectively averaging out between minimizing common-channel interference (CCI) and the multi-user diversity gain.Because residual common-channel interference (CCI) under limited feedback condition, will become bigger along with the increase of received signal to noise ratio (SNR), two kinds of schemes all increase slower at high s/n ratio (SNR) region performance.

To those skilled in the art, obviously the invention is not restricted to the details of above-mentioned example embodiment, and under the situation that does not deviate from spirit of the present invention or essential characteristic, can realize the present invention with other concrete form.Therefore; No matter from which point; All should regard embodiment as exemplary; And be nonrestrictive, scope of the present invention is limited accompanying claims rather than above-mentioned explanation, therefore is intended to the implication of the equivalents that drops on claim and all changes in the scope are included in the present invention.Should any Reference numeral in the claim be regarded as limit related claim.In addition, obviously other unit or step do not got rid of in " comprising " speech, and odd number is not got rid of plural number.A plurality of unit of stating in system's claim or device also can be realized through software or hardware by a unit or device.The first, the second word such as grade is used for representing title, and does not represent any specific order.

Claims (13)

1. method that in the network equipment, is used to carry out user's scheduling based on the wireless communication system of MIMO, wherein, each subscriber equipment comprises the code book collection identical with the network equipment, and wherein, this method may further comprise the steps:

-receive feedback information from N subscriber equipment, be used to characterize the code book index and estimation SINR information of channel response vector separately comprising a said N subscriber equipment;

Wherein, said method is further comprising the steps of:

A. come to select one by one subscriber equipment according to the channel related information of each subscriber equipment feedback; So that the channel response matrix of selected each subscriber equipment and other have selected the combined channel response matrix of subscriber equipment to satisfy predetermined orthogonality condition, and concentrate the corresponding pre-coding matrix of reconstruct by said code book according to selected each subscriber equipment code book index separately that goes out.

2. method according to claim 1, wherein, said step a is further comprising the steps of:

-select to estimate that the maximum subscriber equipment of SINR is as first subscriber equipment;

-based on the code book index of said first subscriber equipment feedback, concentrate the reconstruct precoding vectors by said code book;

Wherein, said step a is further comprising the steps of:

-next the subscriber equipment of selection in non-selected subscriber equipment; And come the corresponding precoding vectors of reconstruct based on said code book index, so that the channel response matrix of said next subscriber equipment and other have selected the combined channel response matrix of subscriber equipment to satisfy predetermined orthogonality condition.

3. method according to claim 2; Wherein, Said predetermined orthogonality condition comprises between channel response matrix and other the combined channel response matrixs of having selected family equipment for use of selected user equipment and satisfies semi-orthogonal property condition, and the estimation SINR value second predetermined condition of selected user equipment.

4. method according to claim 3, wherein, said predetermined orthogonality condition satisfies following formula:

$T_{i+1}=\{k\∈T_i,k\≠\mathrm{\π}\left(i\right)|\frac{d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}=\frac{\frac{1}{\sqrt{2}}{\left|\right|{\hat{h}}_k^H{\hat{h}}_k-{\tilde{g}}_i^H{\tilde{g}}_i\left|\right|}_F}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}>\mathrm{\α}\}$

i←i+1

Wherein, the α value changes in 0.8-0.99 value interval along with the increase (10-10,000) of k.

5. according to each described method in the claim 1 to 4, wherein, the said network equipment comprises BS, Node-B, or network controller.

6. method that in subscriber equipment, is used to carry out user's scheduling based on the wireless communication system of MIMO, wherein, subscriber equipment comprises the code book collection identical with the network equipment, and wherein, this method comprises:

-according to smallest chord apart from rule, by selecting corresponding channel vector in the said code book;

Wherein, said method also comprises:

The SINR value of the channel between-estimation and the affiliated base station;

Wherein, further comprising the steps of:

-code book index of said channel vector correspondence and estimated SINR value are sent to the network equipment.

7. one kind is used to carry out the network equipment that the user dispatches in the wireless communication system based on MIMO, and wherein, each subscriber equipment comprises the code book collection identical with the network equipment, and this network equipment comprises:

Receiving system is used to receive the feedback information from N subscriber equipment, comprising the said N subscriber equipment code book index and estimation SINR information that are used to characterize the channel response vector separately;

User dispatching device; Be used for to select one by one subscriber equipment, be scheduled to orthogonality condition so that the channel response matrix of selected each subscriber equipment has selected the combined channel response matrix of subscriber equipment to satisfy with other according to the channel related information of said N subscriber equipment feedback;

Reconfiguration device is used for the code book index based on selected each subscriber equipment that goes out, and concentrates the corresponding pre-coding matrix of reconstruct by said code book.

8. the network equipment according to claim 7, wherein, wherein, said user dispatching device also comprises:

First choice device is used to select to estimate that the maximum subscriber equipment of SINR is as first subscriber equipment;

Second choice device; Be used for selecting next subscriber equipment at non-selected subscriber equipment; And come the corresponding precoding vectors of reconstruct based on said code book index, so that the channel response matrix of said next subscriber equipment and other have selected the combined channel response matrix of subscriber equipment to satisfy predetermined orthogonality condition.

9. the network equipment according to claim 8; Wherein, Said predetermined orthogonality condition comprises between channel response matrix and other the combined channel response matrixs of having selected family equipment for use of selected user equipment and satisfies semi-orthogonal property condition, and the estimation SINR value second predetermined condition of selected user equipment.

10. the network equipment according to claim 9, wherein, said predetermined orthogonality condition satisfies following formula:

$T_{i+1}=\{k\∈T_i,k\≠\mathrm{\π}\left(i\right)|\frac{d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}=\frac{\frac{1}{\sqrt{2}}{\left|\right|{\hat{h}}_k^H{\hat{h}}_k-{\tilde{g}}_i^H{\tilde{g}}_i\left|\right|}_F}{\max \left(d_{\mathrm{chord}}({\hat{h}}_k,{\tilde{g}}_i)\right)}>\mathrm{\α}\}$

i←i+1

Wherein, the α value changes in 0.8-0.99 value interval along with the increase (10-10,000) of k.

11. according to each described network equipment in the claim 7 to 10, wherein, the said network equipment comprises BS, Node-B, or network controller.

12. a subscriber equipment that in the wireless communication system based on MIMO, is used to carry out user's scheduling, wherein, subscriber equipment comprises the code book collection identical with the network equipment, and wherein, this subscriber equipment comprises:

The 3rd choice device is used for according to smallest chord apart from rule, by selecting corresponding channel vector in the said code book;

Wherein, said subscriber equipment also comprises:

Estimation unit, be used to estimate and affiliated base station between the SINR value of channel;

Wherein, also comprise:

Dispensing device is used for code book index that said channel vector is corresponding and estimated SINR value and sends to the network equipment.

13. the wireless communication system based on MIMO comprises like each described network equipment and subscriber equipment as claimed in claim 12 in the claim 7 to 11.

Images