CN102316598A - Orthogonal random beam forming (PRBF) multi-user dispatching method based on greed beam selection strategy - Google Patents

Abstract

The invention discloses an orthogonal random beam forming (PRBF) multi-user dispatching method based on a greed beam selection strategy, which comprises the following steps that: (1) each user feeds back channel sate information (CSI) to a base station; (2) the dispatching of single beam is supposed for transmitting data, and the base station selects a pair of user beam combinations for forming a dispatching scheme and calculates the system speed at the time; (3) the number of the beams to be supposed to be dispatched is increased, the base station selects a pair of user beam combinations from an undispatched user set and a beam set to be added into the original dispatching scheme, and the corresponding system speed of the updated scheme is calculated; (4) the third step is repeated until the number of the beams to be supposed to be dispatched reaches the dispatchable beam number upper limit; and (5) the base station selects the dispatching scheme most suitable for the current channel environment for realizing the data transmission according to the system speed of each scheme corresponding to the number of the beams to be dispatched. The method has the advantages that the proper beams can be dispatched in a self adaptive way in the ORBF scheme in different channel environment, users can carry out data transmission, and the system performance of the ORBF scheme is greatly improved.

Description

A kind of ORBF multi-user dispatching method based on greedy beam selection strategy

Technical field

The present invention relates to the multiuser MIMO technology, relate to the Adaptive Transmission scheduling strategy of MIMO BC down channel, be specifically related to a kind of ORBF multi-user dispatching method based on greedy beam selection strategy.

Background technology

In the multiuser MIMO downlink system, orthogonal random beam forming (ORBF) advantages such as computation complexity is low owing to having, the CSI feedback quantity is few for the Sharif proposition have caused the concern of Many researchers.When number of users is many, have the progressive performance identical with the DPC algorithm; But when the user was fewer, the systematic function of ORBF algorithm can sharply descend.In addition, under the high s/n ratio environment, the ORBF system can be in " interference-limited " state, at this moment the lifting of the performance of the serious system for restricting of interference meeting between wave beam.And quantity research proves greatly, in the ORBF transmission policy, dispatches all wave beams and is not necessarily the optimal transmission scheme.Therefore, in order to overcome the above-mentioned shortcoming of ORBF, a large amount of researchers have proposed the multi-subscriber dispatching strategy on the basis of traditional ORBF.

Now, the ORBF multi-user dispatching method that existing document proposes also comprises bottom-up scheduling strategy, top-down scheduling strategy and based on the multi-beam selection algorithm of look-up table, describes respectively below except traditional ORBF strategy.

Typical traditional ORBF scheduling strategy is roughly set forth as follows.Do not have the adaptive user beam dispath during traditional ORBF strategy that Sharif proposes, so this algorithm is all dispatched all wave beams at each sending time slots and is carried out transfer of data for the best user of channel circumstance separately.But under most of environment; Dispatch all wave beams and be not necessarily optimum transmission plan; Particularly under the high s/n ratio environment, system is in " interference-limited " state, and the wave beam that at this moment is more prone to dispatch still less influences systematic function to reduce inter-beam interference.So there is bigger performance loss under many circumstances in traditional ORBF.

Typical bottom-up scheduling strategy is roughly set forth as follows.This algorithm is 1 o'clock at the scheduling numbers of beams earlier, and the user for each beam allocation performance behaves oneself best makes up as fixing user wave beam with this.Then, the user that the first step chooses (and their corresponding wave beams) will make up by all possible arrangement mode, and calculate its performance in various scheduling numbers of beams backward.The final scheduling scheme that in all combinations, finds the highest user wave beam combination of systematic function as this data transfer.This algorithm is when actual optimal scheduling numbers of beams is 1, and systematic function has very big improvement.But when the actual schedule numbers of beams was higher, the scheme that draws of this algorithm was not necessarily preferred plan, did not also reach best systematic function even this will make this algorithm dispatch correct numbers of beams.

Typical top-down scheduling strategy is roughly set forth as follows.Completely contradict with bottom-up algorithm, the first step of top-down algorithm is that the hypothesis numbers of beams that is scheduled is N _t, and the user for distributing performance to behave oneself best in each wave beam, match as fixing user wave beam with this.Then, the user that the first step chooses (and their corresponding wave beams) will make up by all possible arrangement mode, and calculate its performance in various possible numbers of beams backward.The final scheduling scheme that in all combinations, finds the highest user wave beam combination of systematic function as this data transfer.When this algorithm was fit to all wave beams of scheduling at current channel circumstance, top-down algorithm can reach best performance.But when the actual schedule numbers of beams reduces, because this user wave beam regular collocation is not necessarily the best pairing of channel conditions at that time, so performance can be lost.

Typically roughly set forth as follows based on look-up table multi-beam selection strategy.Multi-beam selection algorithm based on look-up table can be kept at the best down scheduling numbers of beams of different channels environment in the base station with form of look through analog simulation in advance.In each sending time slots, system can draw the optimal beam number based on current channel circumstance from look-up table, to various possibly the user wave beam combination traversal under this numbers of beams, finds out the optimum down scheduling scheme of system's corresponding scheduling numbers of beams then.This strategy can only provide an approximate scheduling numbers of beams reference value based on look-up table interval, current channel circumstance place.In time varying channel environment complicated and changeable, because the precision problem of searching, this strategy very lets the wave beam of system call number of errors carry out transfer of data easily, is that systematic function has bigger loss.

No matter above-mentioned which kind of user's scheduling strategy all only just can make system reach best performance under specific channel circumstance, can not really make system obtain higher performance according to different channels environment self-adaption scheduling preferred plan.Therefore, be necessary that the ORBF multi-user dispatching method that proposes the various channel circumstances of a kind of self adaptation overcomes above-mentioned defective.

Summary of the invention

The Multi User Adaptive dispatching method that the purpose of this invention is to provide ORBF; Can make the base station of realizing the ORBF scheduling strategy according to the adjustment of different channels environment self-adaption user and the wave beam that will dispatch; Make the ORBF strategy under the different channels environment, also can improve systematic function well, particularly overcome traditional ORBF when number of users is lower or signal to noise ratio low defective of performance higher the time.

To achieve these goals, the invention provides a kind of ORBF multi-user dispatching method, comprise the steps: that (1) each user feeds back to the base station with its channel condition information CSI based on greedy beam selection strategy; (2) supposition scheduling simple beam transmission data, when promptly dispatching numbers of beams B=1, the base station selects a pair of user wave beam to be combined to form scheduling scheme from user's set and beam set, and calculates system's speed of this moment; (3) increase the numbers of beams that supposition is dispatched, the base station selects a pair of user wave beam combination to augment into former scheduling scheme in user's set that is not scheduled and beam set, and calculates the corresponding system speed under the scheme after this renewal; (4) repeating step (3) reaches the base station up to supposition scheduling numbers of beams and can dispatch numbers of beams upper limit N _t(5) according to system's speed of the corresponding scheme of each scheduling numbers of beams, the base station selected scheduling scheme that goes out to be suitable for most current channel circumstance is realized transfer of data.

In one embodiment of the invention, the CSI of said each user feedback is the system gain between each user and all wave beams

Wherein,

Be the channel gain vector between base station and k the user, And 1≤k≤K, K are the total number of users in the sub-district, place, base station; w _iBe i beam forming vector of base station generation,

And 1≤i≤N _t, N _tWave beam sum for antenna for base station formation.In the user feedback CSI stage, each user k must be with N _tIndividual system gain numerical value

And corresponding wave beam numbering i feeds back to the base station.K * N can be set up in the base station after accepting the CSI of all user feedbacks _tAll users of dimension and the system gain matrix G between wave beam promptly can be known whole channel condition information.Wherein ${\left|h_k^T{w}_i\right|}^2\∈G,1\≤k\≤K,1\≤i\≤N_t,$ And

$G=\left[\begin{array}{cccc}{\left|h_1^{\mathrm{<figure-callout\; id="1"\; label="T\; w"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">T</figure-callout>}}{w}_{}{}_1\right|}^2& {\left|h_1^{\mathrm{<figure-callout\; id="2"\; label="T\; w"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">T</figure-callout>}}{w}_{}{}_2\right|}^2& L& {\left|h_1^T{w}_{N_t}\right|}^2\\ {\left|h_2^{\mathrm{<figure-callout\; id="1"\; label="T\; w"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">T</figure-callout>}}{w}_{}{}_1\right|}^2& {\left|h_2^{\mathrm{<figure-callout\; id="2"\; label="T\; w"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">T</figure-callout>}}{w}_{}{}_2\right|}^2& L& {\left|h_2^T{w}_{N_t}\right|}^2\\ L& L& O& L\\ {\left|h_{\mathrm{<figure-callout\; id="1"\; label="K\; T\; w"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">K</figure-callout>}}^T{w}_{}{}_1\right|}^2& {\left|h_{\mathrm{<figure-callout\; id="2"\; label="K\; T\; w"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">K</figure-callout>}}^T{w}_{}{}_2\right|}^2& L& {\left|h_K^T{w}_{N_t}\right|}^2\end{array}\right].$

In another embodiment of the present invention, said each user realizes zero defect CSI feedback through MIMO MAC up channel.

In an embodiment more of the present invention, best user of base station selected channel circumstance and corresponding wave beam form scheduling scheme in the said step (2).

In another embodiment of the present invention, base station selected under simple beam in the said step (2), the user that channel Signal to Interference plus Noise Ratio SINR value is maximum.

In an embodiment more of the present invention; The user wave beam that increases in the said step (3) is to all must being under current scheduling numbers of beams; Based on the channel circumstance of former scheduling scheme best user and corresponding wave beam thereof, even maximum user and the corresponding wave beam thereof of the SINR value of system.

In another embodiment of the present invention, said step (3) is specially: (31) order scheduling numbers of beams B=B+1, and the user wave beam scheduling scheme the selected set of order scheduling numbers of beams when being B-1 is S; (32) base station is in non-selected user wave beam set; Select a kind of user wave beam combination to augment into scheduling scheme S set; Selecteed user wave beam combination is under the current scheduling numbers of beams B; After augmenting the scheduling scheme when into the scheduling numbers of beams is B-1; The user and the corresponding wave beam thereof of all big SINR value when making system obtain than select all the other user wave beam combinations, the scheduling scheme after augmenting at this moment can let on the basis of the scheduling scheme S set of system before this is augmented, and reach following the highest system speed that can reach of current scheduling numbers of beams; (33) calculate under the current scheduling numbers of beams system's speed that the scheduling scheme after augmenting reaches.

In another embodiment of the present invention; Described system speed is under the multiuser MIMO environment, system is issued in the current scheduling scheme and speed (Sum-rate), then; After accomplished said step (2), (3), (4), system will obtain the N identical with the wave beam total quantity _tIndividual and speed, each with speed corresponding to a kind of scheduling scheme of dispatching under numbers of beams and this numbers of beams.

In an embodiment more of the present invention, be suitable for current basis for estimation of carrying out the user wave beam scheduling scheme of transfer of data in the said step (5) most and be specially: at final N _tPlant in the scheduling scheme, the maximum scheme of correspondence and speed of selecting is carried out transfer of data as the optimal scheduling scheme confession base station of current time slots.

Compared with prior art; The ORBF multi-user dispatching method that the present invention is based on greedy beam selection strategy can carry out transfer of data according to suitable user and the wave beam of different channels environment self-adaption scheduling, efficiently solve ORBF at number of users less and signal to noise ratio higher in performance receive the defective of serious restriction.Overcome bottom-up beam dispath strategy, top-down beam dispath strategy simultaneously and can only under the particular channel environment, just can make system obtain the defective of performance improvement significantly based on look-up table multi-beam selection strategy etc.In a word, this method can be improved ORBF systematic function under the different channels environment significantly.

Through following description and combine accompanying drawing, it is more clear that the present invention will become, and these accompanying drawings are used to explain embodiments of the invention.

Description of drawings

Fig. 1 is the flow chart that the present invention is based on the ORBF multi-user dispatching method of greedy beam selection strategy.

Fig. 2 is the residing typical multiuser MIMO BC downlink broadcast channel circumstance of the ORBF multi-user dispatching method based on greedy beam selection strategy shown in Figure 1.

Fig. 3 is shown in Figure 1 based on each user feedback channel condition information sketch map in the ORBF multi-user dispatching method of greedy beam selection strategy.

Fig. 4 a-4d is a screening pairing process of utilizing greedy algorithm that user and wave beam are carried out in the ORBF multi-user dispatching method based on greedy beam selection strategy shown in Figure 1.

Fig. 5 is for utilizing the sketch map of greedy algorithm dispatched users and the laggard data transfer of wave beam in the ORBF multi-user dispatching method based on greedy beam selection strategy shown in Figure 1.

Embodiment

With reference now to accompanying drawing, describe embodiments of the invention, the similar elements label is represented similar elements in the accompanying drawing.

The ORBF multi-user dispatching method that the present invention is based on greedy beam selection strategy is based on to be realized under the typical multiuser MIMO down channel environment: in MIMO BC downlink broadcast channel, cell base station BS disposes N _tRoot antenna, sub-district have K single antenna user; Wave beam and the channel between each user that each antenna forms are separate rayleigh fading channels; Each user terminal can obtain complete CSI, and can utilize MIMO MAC up channel low speed zero defect feedback CSI.

Before setting forth the ORBF multi-user dispatching method of present embodiment based on greedy beam selection strategy, the following notion that relates in the said method of explanation earlier:

Signal to Interference plus Noise Ratio (SINR): for many with the MIMO downlink system in the ratio of the signal power that receives of terminal and noise power, interference power.In the ORBF scheduling strategy, if k the needed information of user is transmitted by wave beam i, then this user's the signal that receives is:

$r_k=h_k^T{W}_B{s}_B+n_k=h_k^T{W}_i{S}_i+\underset{j\&Element;B,j\&NotEqual;i}{\mathrm{\&Sigma;}}{h}_k^T{w}_j{s}_j+n_k$

Wherein, Be the channel gain matrix between base station and k the user,

B is the current scheduling beam subset in base station, and B=card (B) is corresponding scheduling numbers of beams; W _BThe submatrix that generates for the base station, and w about the random beam forming matrix of scheduling beam subset B _i∈ W _B, i ∈ B; s _BThe transmit data set subclass that will send for the base station, and s about scheduling beam subset B _i∈ s _B, i ∈ B; n _kBe the additive white Gaussian noise that channel experienced between base station and k the user.At this moment; Transmit on the wave beam of data to each if the total emission power of base station is E

and base station transmitting power mean allocation, then the transmitting power of each wave beam acquisition is P/B.Can get thus, the average signal-to-noise ratio of transmission system is ρ=P/ σ ²So the Signal to Interference plus Noise Ratio SINR that we can obtain between user k and the i wave beam is:

${\mathrm{SINR}}_{k,i}=\frac{{\left|h_k^T{w}_i\right|}^2}{B/\mathrm{\&rho;}+{\mathrm{\&Sigma;}}_{j\&Element;B,j\&NotEqual;i}{\left|h_k^T{w}_j\right|}^2}$

And speed (Sum-rate): for the maximum of all channel transmission rate sums of system and speed just is referred to as system and capacity.So as base station scheduling N _tB in an individual wave beam wave beam carries out transfer of data, and during the wave beam that the power P mean allocation is used for to each launching and the speed expression formula be:

$R\left(B\right)\&cong;\underset{i\&Element;B}{\mathrm{\&Sigma;}}{\log }_2(1+\underset{1\&le;k\&le;K}{\mathrm{<figure-callout\; id="1"\; label="max"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">max</figure-callout>}}{\mathrm{SINR}}_{k,i}\left(B\right))$

Wherein,

is among K the user, the be scheduled maximum SINR value of wave beam i of correspondence.

Specify the flow process of present embodiment below based on the ORBF multi-user dispatching method of greedy beam selection strategy.In conjunction with Fig. 1, Fig. 3, Fig. 4 a-4d, Fig. 5, suppose that base station BS forms N altogether _t=4 wave beam A, B, C, D, there are K=8 single antenna user a, b, c, d, e, f, g, h in the sub-district, then said method comprising the steps of:

Step S1, base station BS let all N that formed by antenna _tIndividual wave beam utilizes MIMO BC down channel all K users broadcasting training symbols in the sub-district, and each user k receives the system gain that calculates behind the broadcast singal separately for each wave beam i

In the user feedback CSI stage, each user k utilizes the MIMOMAC feedback channel N separately _tIndividual system gain

And corresponding wave beam numbering i feeds back to base station BS (like Fig. 3), and base station BS is set up the system gain matrix G between current all users and wave beam according to the CSI of all user feedbacks, and the current available user of initialization gathers K ₁=1 .., K}, current available beam set B ₁=1 .., N _t, degree of recruiting scheme

(like Fig. 3, K ₁={ k _a, k _b, k _c, k _d, k _e, k _f, k _g, k _h, B ₁={ i _A, i _B, i _C, i _D);

Step S2, order scheduling numbers of beams B=1, base station BS are according to system gain matrix G, from selectable user set K ₁, beam set B ₁In select a pair of under simple beam transfer of data situation, the best user wave beam of channel circumstance combination (k ₁, i ₁), this user wave beam combination meets the requirements:

$({\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">k</figure-callout>}}_1,i_1)={\arg \max }_{(k,i)}\mathrm{\&rho;}{\left|h_k^T{w}_i\right|}^2,\&ForAll;(k,i)\&Element;{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">K</figure-callout>}}_1\&times;{\mathrm{<figure-callout\; id="1"\; label="B"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">B</figure-callout>}}_1$

Wherein, (k ₁, i ₁) being the corresponding numbering of this user wave beam combination, ρ is system's average signal-to-noise ratio, and with (k ₁, i ₁) add among the scheduling scheme S, make S={ (k ₁, i ₁) (like Fig. 4 a, S={ (k _e, i _B));

Step S3 calculated when this moment, simple beam was dispatched, system and speed during ORBF scheduling S:

${\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">R</figure-callout>}}_1=\mathrm{\&Theta;}\left(\mathrm{\&rho;}{\left|h_{k_1}^T{w}_{i_1}\right|}^2\right)$

Wherein, Θ (x)=log ₂(1+x)

Step S4, order scheduling numbers of beams B=B+1, base station BS makes selectable user set K _B=K _B-1-{ k _B-1, optional beam set B _B=B _B-1-{ i _B-1, k wherein _B-1After adding scheduling scheme, make the scheduling numbers of beams become the user of B-1, i _B-1Make the scheduling numbers of beams become the wave beam of B-1 in the scheduling scheme for adding;

Step S5, base station BS is according to the selectable user set K that obtains among the step S4 _BWith beam set B _BDo not carried out various combination pairings to selecting user and wave beam;

Step S6, base station BS therefrom is chosen under the current scheduling numbers of beams according to the various combination pairings that obtain among the step S5, and channel circumstance best users and corresponding wave beam thereof are formed user wave beam combination (k _B, i _B), this user wave beam combination meets the requirements:

$(k_B,i_B)=$

${\arg \max }_{(k,i)}\left\{\begin{array}{c}\mathrm{\&Theta;}\left(\frac{{\left|h_k^T{w}_i\right|}^2}{B/\mathrm{\&rho;}+{\mathrm{\&Sigma;}}_{s=1}^{B-1}{\left|h_k^T{w}_{i_s}\right|}^2}\right)\\ +\underset{p=1}{\overset{B-1}{\mathrm{\&Sigma;}}}\mathrm{\&Theta;}\left(\frac{{\left|h_{k_p}^T\right|}^2}{B/\mathrm{\&rho;}+{\left|h_{k_p}^T{w}_i\right|}^2+{\mathrm{\&Sigma;}}_{s=1,s\&NotEqual;p}^{B-1}{\left|h_{k_p}^T{w}_{i_s}\right|}^2}\right)\end{array}\right\},$

$\&ForAll;(k,i)\&Element;K_B\&times;B_B$

Wherein, (k _B, i _B) be the numbering of this user wave beam combination correspondence, Θ (x)=log ₂(1+x), this user wave beam combination (k _B, i _B) be at current selectable user beam set K _B, B _BIn; Can make system on the basis of original scheduling scheme S; The user wave beam combination of all big SINR value can make system reach following the highest system speed that can reach of current scheduling numbers of beams when obtaining the current scheduling numbers of beams down than all the other user wave beam combinations of selection, should make up (k _B, i _B) add among the scheduling scheme S i.e. S=S+{ (k _B, i _B);

Step S7 calculates when current scheduling numbers of beams B, system and speed during ORBF scheduling S:

$R_B=\underset{p=1}{\overset{B}{\mathrm{\&Sigma;}}}\mathrm{\&Theta;}\left(\frac{{\left|h_{k_p}^T{w}_{i_p}\right|}^2}{B/\mathrm{\&rho;}+{\mathrm{\&Sigma;}}_{s=1,s\&NotEqual;p}^B{\left|h_{k_p}^T{w}_{i_s}\right|}^2}\right)$

Wherein, Θ (x)=log ₂(1+x);

Step S8 judges whether scheduling numbers of beams B counts N less than main aerial _t, promptly whether B meets B＜N _t, if change step S4 (like Fig. 4 b-4d), if not, continue next step;

Step S9, base station BS is finally obtaining N _tPlant in the scheduling scheme and select corresponding system and speed R _B, 1≤B≤N _tThe scheme S that numerical value is maximum _End, S _EndMeet following requirement:

B ^*＝argmax _BR _B，1≤B≤N _t

$S_{\mathrm{end}}=\{({\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="HDA0000091984940000011.png"\; state="\{\{state\}\}">k</figure-callout>}}_1,i_1),...,(k_{B^{*}},i_{B^{*}})\}$

Wherein, B ^*For with the corresponding scheduling numbers of beams of the maximum scheme of speed, S _EndCorrespond to the preceding B of S ^*The final scheduling scheme that individual user wave beam combination is formed, base station BS is according to final scheduling numbers of beams B ^*With scheduling scheme S _EndRealize the adaptive scheduling (like Fig. 5) of current time slots, and current system and speed do

Finish;

By on can find out; Present embodiment can carry out transfer of data according to suitable user and the wave beam of different channels environment self-adaption scheduling based on the ORBF multi-user dispatching method of greedy beam selection strategy; This selection scheduling process is constantly evolution on existing scheduling scheme; Can maximally utilise existing scheduling scheme, avoid increasing the scheduling numbers of beams and need screen pairing again all user wave beam.Through this method, efficiently solve ORBF at number of users less and signal to noise ratio higher in systematic function receive the defective of serious restriction.Overcome bottom-up beam dispath strategy, top-down beam dispath strategy simultaneously and can only under the particular channel environment, just can make system obtain the defective of performance improvement significantly, made system when implementing the ORBF scheme, under different signal to noise ratio environment, can both obtain significantly performance improvement based on look-up table multi-beam selection strategy etc.

Invention has been described more than to combine most preferred embodiment, but the present invention is not limited to the embodiment of above announcement, and should contain various modification, equivalent combinations of carrying out according to essence of the present invention.

Claims (9)

1. the ORBF multi-user dispatching method based on greedy beam selection strategy comprises the steps:

(1) each user feeds back to the base station with its channel condition information (CSI);

(2) supposition scheduling simple beam transmission data, when promptly dispatching numbers of beams B=1, the base station selects a pair of user wave beam to be combined to form scheduling scheme from user's set and beam set, and calculates system's speed of this moment;

(3) increase the numbers of beams that supposition is dispatched, the base station selects a pair of user wave beam combination to augment into former scheduling scheme in user's set that is not scheduled and beam set, and calculates the corresponding system speed under the scheme after this renewal;

(4) repeating step (3) reaches the base station up to supposition scheduling numbers of beams and can dispatch numbers of beams upper limit N _t

(5) according to system's speed of the corresponding scheme of each scheduling numbers of beams, the base station selected scheduling scheme that goes out to be suitable for most current channel circumstance is realized transfer of data.

2. the ORBF multi-user dispatching method based on greedy beam selection strategy as claimed in claim 1 is characterized in that, the CSI of said each user feedback is the system gain between each user and all wave beams of base station

Wherein,

Be the channel gain vector between base station and k the user,

And 1≤k≤K, K are the total number of users in the sub-district, place, base station, w _iBe i beam forming vector of base station generation,

And 1≤i≤N _t, N _tBe the wave beam sum of antenna for base station formation,

Then; In the user feedback CSI stage; Each user k must feed back to the base station with Nt system gain numerical value

and corresponding wave beam numbering i thereof

Then, K * N can be set up in the base station behind the CSI that receives all user feedbacks _tAll users of dimension and the system gain matrix G between wave beam, thus can know whole channel condition information, wherein ${\left|h_k^T{w}_i\right|}^2\&Element;G,1\&le;k\&le;K,1\&le;i\&le;N_t,$ And

$G=\left[\begin{array}{cccc}{\left|h_1^T{w}_1\right|}^2& {\left|h_1^T{w}_2\right|}^2& L& {\left|h_1^T{w}_{N_t}\right|}^2\\ {\left|h_2^T{w}_1\right|}^2& {\left|h_2^T{w}_2\right|}^2& L& {\left|h_2^T{w}_{N_t}\right|}^2\\ L& L& O& L\\ {\left|h_K^T{w}_1\right|}^2& {\left|h_K^T{w}_2\right|}^2& L& {\left|h_K^T{w}_{N_t}\right|}^2\end{array}\right].$

3. the ORBF multi-user dispatching method based on greedy beam selection strategy as claimed in claim 2 is characterized in that, each user realizes zero defect CSI feedback through MIMO MAC up channel.

4. the ORBF multi-user dispatching method based on greedy beam selection strategy as claimed in claim 1 is characterized in that, in the said step (2), user that base station selected channel circumstance is best and corresponding wave beam form scheduling scheme.

5. the ORBF multi-user dispatching method based on greedy beam selection strategy as claimed in claim 1 is characterized in that, and is base station selected under simple beam in the said step (2), the user that channel Signal to Interference plus Noise Ratio SINR value is maximum.

6. like the described ORBF multi-user dispatching method in one of claim 4 or 5 based on greedy beam selection strategy; It is characterized in that; The user wave beam that increases in the said step (3) is to all must being under current scheduling numbers of beams; Based on the channel circumstance of former scheduling scheme best user and corresponding wave beam thereof, even maximum user and the corresponding wave beam thereof of the SINR value of system.

7. like the described ORBF multi-user dispatching method of one of claim 1-5, it is characterized in that said step (3) is specially based on greedy beam selection strategy:

The user wave beam scheduling scheme of having selected set when (31) order scheduling numbers of beams B=B+1, and order scheduling numbers of beams is B-1 is S;

(32) base station is in non-selected user wave beam set; Select a kind of user wave beam combination to augment into scheduling scheme S set; Selecteed user wave beam combination is under the current scheduling numbers of beams B; After augmenting the scheduling scheme when into the scheduling numbers of beams is B-1; The user and the corresponding wave beam thereof of all big SINR value when making system obtain than select all the other user wave beam combinations, the scheduling scheme after augmenting at this moment can let on the basis of the scheduling scheme S set of system before this is augmented, and reach following the highest system speed that can reach of current scheduling numbers of beams;

(33) calculate under the current scheduling numbers of beams system's speed that the scheduling scheme after augmenting reaches.

8. the ORBF multi-user dispatching method based on greedy beam selection strategy as claimed in claim 7 is characterized in that described system speed is under the multiuser MIMO environment, system is issued in the current scheduling scheme and speed (Sum-rate),

Then, after accomplished said step (2), (3), (4), system will obtain the N identical with the wave beam total quantity _tIndividual and speed, each with speed corresponding to a kind of scheduling scheme of dispatching under numbers of beams and this numbers of beams.

9. the ORBF multi-user dispatching method based on greedy beam selection strategy as claimed in claim 8 is characterized in that, is suitable for current basis for estimation of carrying out the user wave beam scheduling scheme of transfer of data in the said step (5) most and is specially:

At final N _tPlant in the scheduling scheme, the maximum scheme of correspondence and speed of selecting is carried out transfer of data as the optimal scheduling scheme confession base station of current time slots.

Images