CN101674273A - Multi-user dispatching method, multi-user dispatching device, information feedback device, base station and mobile station - Google Patents

Abstract

The invention provides a multi-user dispatching method, which comprises that: a base station sections OFDM sub-carrier and separately creates Nt orthogonal wave beams for each sub-carrier section to form a wave beam set of the each sub-carrier section, wherein Nt is a natural number; aiming at the wave beam set of the each sub-carrier section, each mobile station determines a wave beam with maximum SNR, and feeds back SNR information and wave beam identification information on the wave beam to the base station; on the premise that the corresponding adapted wave beam is not occupied, the base station selects the mobile station with maximum SNR to be added into a user dispatching set in all the mobile stations performing the information feedback in turn, and adds the adapted wave beam corresponding to the mobile station into a dispatching wave beam set; and the base station detects whether the dispatched power distribution result meets the predetermined constraint conditions, and selectsthe dispatching use set using maximum system flow, the corresponding wave beam configuration and the power distribution result. The invention also provides a multi-user dispatching device, an information feedback device, the base station and the mobile station.

Description

Multi-user dispatching method, multi-user dispatching device, information feedback device, base station and travelling carriage

Technical field

The present invention relates to the multi-subscriber dispatching in the communication technical field, particularly, relate to a kind of multi-user dispatching method, a kind of multi-user dispatching device, a kind of information feedback device, a kind of base station and a kind of travelling carriage, being applied to random wave bundle forms in OFDM (OFDM) system, have lower complexity, and can joint Power distribute.

Background technology

Random wave bundle forms the angle of technology from system, has proposed the notion of multi-user diversity.By this selectivity gain, can under the less prerequisite of user feedback amount, realize the higher system flow.Form the basis with quadrature multi-beam random wave bundle, carry out multi-subscriber dispatching, by the user that adapts for each beam allocation as the dispatched users collection, and in conjunction with power distribution method, adopt the appropriate users dispatching method, can realize the maximization of average system flow.

In some technical literatures, following 3 kinds of multi-user dispatching methods are proposed:

(1) exhaust algorithm: each user measures the channel information of equivalent channel, the channel information and the channel number of feedback optimum channel.Exhaust algorithm is enumerated each possible user combination, and attempts carrying out best power and distribute.Referring to document: J.L.Vicario, wait " Adaptive BeamSelction techniques for opportunistic beamforming ", PIMRC ' 06,2006.(" being used for the adaptive beam selection technology that random wave bundle forms ")

(2) the empty random wave bundle formation method of dividing: broadcast with a plurality of orthogonal beams, according to only wave beam sequence number of each user feedback and equivalent channel, each beam selection optimal user is carried out being in the base station.Referring to document: Kai-Kit Wong, Deng " Capacity enhancement inthe downlink using space-division opportunistic beamforming ", Wireless Communications, Networking and Mobile Computing, 2005.(" adopting empty capacity gain of dividing random wave bundle to form ")

(3) greedy algorithm: according to the channel information of user feedback, the base station is selected the user of channel condition the best earlier, and after each circulation in, distribute according to best power, select the user of an optimum.After making that this user adds the dispatched users collection, can obtain maximum flow system flow.Referring to document: J.L.Vicario, wait " Adaptive Beam Selctiontechniques for opportunistic beamforming ", PIMRC ' 06,2006.(" being used for the adaptive beam selection technology that random wave bundle forms ")

Exhaust algorithm is fundamental method in the dispatching method, and it can realize global optimum, but algorithm complex is very high.A kind of as dispatching method, greedy algorithm is with respect to exhaust algorithm, and complexity is little a lot.When attempting carrying out allocation schedule, most prior aries have all been used greedy algorithm.Along with the increase of future broadband wireless communication systems antenna number, the complexity of greedy algorithm also can increase but in fact.If simultaneous user is many in the system, greedy algorithm still will be paid very big cost and attempt carrying out user's scheduling and power division.The empty computation complexity of random wave bundle formation method that divides is low, but has only selected the user of minority to dispatch simply, and does not carry out power division, and therefore the flow system flow that obtains is lower for exhaust algorithm.

Summary of the invention

The objective of the invention is at average system flow in the prior art lowlyer, or implementation complexity problem of higher provides a kind of random wave bundle to form the multi-user dispatching method that joint Power is distributed.In the present invention, by adopting the signal processing method with the segmentation of OFDM subcarrier, the frequency domain that strengthens channel response rises and falls.And the present invention also adopts the wave beam of quadrature, by training the interference of eliminating between different beams.On this basis, made full use of the characteristics of ofdm system, number of attempt less user select and power division, reduced algorithm complex significantly.Simultaneously, realized the flow system flow very approaching with optimal scheduling.The present invention has solved the technical problem of prior art scheme algorithm complexes such as greedy algorithm higher (particularly at user's high algorithm complex more for a long time) in conjunction with the technical scheme of greedy algorithm with optimal power allocation.The present invention has solved empty minute wave beam simultaneously and has formed the lower problem of average system flow in the technical scheme.

To achieve these goals, according to first scheme of the present invention, a kind of multi-user dispatching method has been proposed, being applied to random wave bundle forms in the OFDM ofdm system, described multi-user dispatching method may further comprise the steps: the base station is with the segmentation of OFDM subcarrier, and be each sub-carrier section, create N independently _tIndividual orthogonal beams forms the beam set of each sub-carrier section, wherein N _tIt is natural number; At the beam set of each sub-carrier section, each travelling carriage determines to have the wave beam of peak signal noise ratio SNR, and to the wave beam identification information of base station feedback SNR information and described wave beam; The travelling carriage that the base station is selected to have maximum S R in having carried out all travelling carriages of feedback information adds the dispatched users collection, and the pairing adaptive wave beam of this travelling carriage is added scheduling wave beam collection; For other travelling carriages except travelling carriage with maximum S R, under the unappropriated prerequisite of corresponding adaptive wave beam, the travelling carriage that the base station is selected to have maximum S R successively attempts adding the dispatched users collection, and attempt corresponding adaptive wave beam is added scheduling wave beam collection, check whether dispatched power distribution result satisfies predetermined constraint conditions; If each the trial all succeedd, promptly each dispatched power distribution result all satisfies predetermined constraint conditions, and then the base station is attempted N at most _t-1 time,, then no longer carry out follow-up trial if certain attempts not success; The base station selected dispatched users collection of flow system flow maximum, the beam configuration that adapts and the power distribution result of making.

Preferably, described multi-user dispatching method can also comprise: the base station is loaded into each beam set on the corresponding OFDM sub-carrier section, goes out from antenna transmission.

Preferably, described multi-user dispatching method can also comprise: this sub-district or beam set that sector base stations sent are monitored and detected to each travelling carriage from each OFDM sub-carrier section, estimates the SNR of each wave beam in the described beam set.More preferably, each travelling carriage is selected described wave beam with maximum S R from the SNR of each wave beam of estimating.More preferably, with the wave beam number N in described maximum S R and the described beam set _tMultiply each other, obtain maximum simple beam SNR, and replace maximum S R, feed back described maximum simple beam SNR.

Preferably, in described OFDM subcarrier division step, the OFDM subcarrier is equally divided into the Q section, Q is the integer greater than 1.

Preferably, the wave beam number N in the beam set of each sub-carrier section _tMutually the same, and beam set has nothing in common with each other.

Preferably, in all sub-carrier section, M had the sub-carrier section of maximum S R before each travelling carriage was determined, and only had the SNR information and the wave beam identification information of the wave beam of maximum S R in this M of base station feedback sub-carrier section.More preferably, the wave beam identification information that has the wave beam of maximum S R in the described M sub-carrier section comprises the sign of sub-carrier section and the sign of wave beam.

Preferably, described predetermined constraint conditions is: dispatched power distribution result does not comprise 0 and 1 between 0 and 1.

Preferably, the base station is according to selected dispatched users collection, the beam configuration that adapts and power distribution result, the down user data of each travelling carriage is loaded into the adaptive wave beam of this travelling carriage, carries out power division according to power distribution result, and send to each travelling carriage.

Preferably, each travelling carriage is according to correct subcarrier segmentation and utilize orthogonality between wave beam, filters the down user data of removing other travelling carriages, obtains the down user data of this travelling carriage.

According to alternative plan of the present invention, a kind of multi-user dispatching device has been proposed, be applied to random wave bundle and form in the OFDM ofdm system, described multi-user dispatching device comprises: the wave beam generation unit, be used for the segmentation of OFDM subcarrier, and be each sub-carrier section, create N independently _tIndividual orthogonal beams forms the beam set of each sub-carrier section, wherein N _tIt is natural number; Scheduling and power distributing unit, be used for beam set at each sub-carrier section, the travelling carriage of selecting to have peak signal noise ratio SNR in having carried out all travelling carriages of feedback information adds the dispatched users collection, and the pairing adaptive wave beam of this travelling carriage is added scheduling wave beam collection; For other travelling carriages except travelling carriage with peak signal noise ratio SNR, under the unappropriated prerequisite of corresponding adaptive wave beam, the travelling carriage of selecting successively to have maximum S R attempts adding the dispatched users collection, and attempt corresponding adaptive wave beam is added scheduling wave beam collection, check whether dispatched power distribution result satisfies predetermined constraint conditions; If each the trial all succeedd, promptly each dispatched power distribution result all satisfies predetermined constraint conditions, then attempts N at most _t-1 time,, then no longer carry out follow-up trial if certain attempts not success; Selection makes the dispatched users collection of flow system flow maximum, the beam configuration that adapts and power distribution result.

Preferably, described multi-user dispatching device can also comprise: data load and transmitter unit, be used for each beam set is loaded into corresponding OFDM sub-carrier section, and go out from antenna transmission.

Preferably, described wave beam generation unit is equally divided into the Q section with the OFDM subcarrier, and Q is the integer greater than 1.

Preferably, the wave beam number N in the beam set of each sub-carrier section _tMutually the same, and beam set has nothing in common with each other.

Preferably, described predetermined constraint conditions is: dispatched power distribution result does not comprise 0 and 1 between 0 and 1.

According to third party's case of the present invention, a kind of base station has been proposed, comprise the described multi-user dispatching device of alternative plan according to the present invention.

Preferably, described base station can also comprise: user data loads and transmitter unit, be used for according to selected dispatched users collection, the beam configuration that adapts and power distribution result, the down user data of each travelling carriage is loaded into the adaptive wave beam of this travelling carriage, carry out power division according to power distribution result, and send to each travelling carriage.

According to cubic case of the present invention, a kind of information feedback device has been proposed, be applied to random wave bundle and form in the OFDM ofdm system, form in the OFDM ofdm system at described random wave bundle, the OFDM subcarrier is by segmentation, and is each sub-carrier section, creates N independently _tIndividual orthogonal beams forms the beam set of each sub-carrier section, wherein N _tIt is natural number, described information feedback device comprises: receive and detecting unit, be used for monitoring and detect this sub-district or beam set that sector base stations sent, estimate the signal noise ratio SNR of each wave beam in the described beam set from each OFDM sub-carrier section; And feedback information generates and transmitter unit, is used for the beam set at each sub-carrier section, determines to have the wave beam of maximum S R, and to the wave beam identification information of base station feedback SNR information and described wave beam.

According to the 5th scheme of the present invention, a kind of information feedback device has been proposed, be applied to random wave bundle and form in the OFDM ofdm system, form in the OFDM ofdm system at described random wave bundle, the OFDM subcarrier is by segmentation, and is each sub-carrier section, creates N independently _tIndividual orthogonal beams forms the beam set of each sub-carrier section, wherein N _tIt is natural number, described information feedback device comprises: receive and detecting unit, be used for monitoring and detect this sub-district or beam set that sector base stations sent, estimate the signal noise ratio SNR of each wave beam in the described beam set from each OFDM sub-carrier section; And feedback information generation and transmitter unit, be used for beam set at each sub-carrier section, determine to have the wave beam of maximum S R, with the wave beam number N in described maximum S R and the described beam set _tMultiply each other, obtain maximum simple beam SNR, and to the wave beam identification information of maximum simple beam SNR information of base station feedback and described wave beam.

Preferably, according to the of the present invention the 4th or the 5th scheme, in all sub-carrier section, described feedback information generates and transmitter unit determines that preceding M has the sub-carrier section of maximum S R, and only has the SNR information and the wave beam identification information of the wave beam of maximum S R in this M of base station feedback sub-carrier section.More preferably, the wave beam identification information that has the wave beam of maximum S R in the described M sub-carrier section comprises the sign of sub-carrier section and the sign of wave beam.

According to the 6th scheme of the present invention, a kind of travelling carriage has been proposed, comprise according to the of the present invention the 4th or the 5th described multi-user dispatching device of scheme.

Preferably, described travelling carriage can also comprise: user data receives and detecting unit, is used for according to correct subcarrier segmentation and utilizes orthogonality between wave beam, filters the down user data of removing other travelling carriages, obtains the down user data of this travelling carriage.

The invention has the advantages that: utilize the wave beam of quadrature multi-beam to form ofdm system, realized the higher system flow.By adopting the signal processing method with the segmentation of OFDM subcarrier, the frequency domain that strengthens channel response rises and falls.And the beam set of employing quadrature, eliminated the interference between the different beams, realized the independent detection of a plurality of equivalent channel.The user only need feed back SNR and wave beam sequence number, thereby has reduced user uplink feedback data amount.By quick greedy algorithm, can finish user's scheduling and power division with lower algorithm complex based on ordering.Especially along with the increase of number of users, can not increase time cost according to multi-user dispatching method of the present invention; Even number of transmit antennas increases, also only be linear growth according to the time cost of multi-user dispatching method of the present invention.So the present invention has realized the higher system flow in the algorithm complex that significantly reduces user's scheduling and power division.The present invention have between spectrum reuse coefficient height, user and base station feedback less, realize simple and be beneficial to advantage such as practicing.

Description of drawings

In conjunction with the accompanying drawings to the detailed description of non-limiting example of the present invention, above-mentioned and other purposes of the present invention, feature and advantage will be clearer according to following, in the accompanying drawing:

Fig. 1 is the block diagram according to base station of the present invention;

Fig. 2 is the block diagram according to travelling carriage of the present invention;

Fig. 3 is the flow chart according to multi-user dispatching method of the present invention; And

Fig. 4 be according to of the present invention, based on the flow chart of quick greedy algorithm of ordering.

Embodiment

Hereinafter the present invention will be described with reference to the accompanying drawings.In the following description, some specific embodiments just are used for purpose of description, and should not be construed as any limitation of the invention, and they are example of the present invention only.Although might blur for the understanding of the present invention, will omit conventional structure or structure.

At first, basic principle of operation of the present invention is elaborated.

Technical scheme of the present invention can comprise the steps:

Step 1: the OFDM subcarrier is divided into the Q section, and is each sub-carrier section, create N independently _tThe N of individual quadrature _tThe dimension wave beam forms Q beam set;

Step 2: each beam set is loaded into the OFDM sub-carrier section accordingly, and goes out from antenna transmission;

Step 3: the user is from each group OFDM sub-carrier section monitoring and detect this sub-district or the beam set of sector base stations transmission, estimates the relative equivalent channel of each wave beam, and signal calculated noise ratio (SNR).For each sub-carrier section, N from it _tPick out the wave beam of SNR maximum in the individual wave beam, the SNR when estimating transmission data separately, and this SNR and corresponding wave beam sequence number fed back to the base station;

Step 4: the base station is according to the SNR of user feedback and corresponding wave beam sequence number, by quick greedy algorithm based on ordering, and for each sub-carrier section is determined the dispatched users collection, and the power allocation scheme of the adaptive wave beam of dispatched users;

Step 5: the specified adaptive wave beam of this dispatched users is arrived with the data load of each dispatched users in the base station, power distribution result according to power allocation scheme is carried out power division, and is sent the data of each dispatched users by transmitting antenna by the associated sub-carrier section of each adaptive beam set;

Step 6: each dispatched users filters out data separately from each sub-carrier section.

In described step 1: the OFDM subcarrier is equally divided into the Q section.According to the statistical property of down channel, be each subcarrier segmentation, generate a virtual subscriber channel.At each time slot at first, utilize this pseudo channel coupling to generate N _tThe N of individual quadrature _tThe dimension wave beam is so that the average signal-to-noise ratio maximization is called beam set W _q=[w _{Q, 1}..., w _{Q, Nt}].If this channel matrix is a full rank, the right matrix that obtains by singular value decomposition just can be used as this N _tThe N of individual quadrature _tThe dimension wave beam.OFDM subcarrier segmentation method all is definite known at base station end and user side, and identical.Be not limited to specific wave beam generation method, according to the channel statistical characteristic, the beam set that generates quadrature at random gets final product.The unnecessary correlation that exists between the wave beam collection.

In described step 2: for q subcarrier segmentation (q=1,2 .., Q), with known symbol s _iMultiply by with the related beam set of this subcarrier segmentation in i wave beam w _i, and be loaded on the subcarrier of q sub-carrier section.Pass through the IFFT conversion, and export by antenna.For the wave beam on the same sub-carrier section, the known symbol sequence of loading is mutually orthogonal.The known array that is loaded all determines at base station end and user side, and identical.

In described step 3: the user passes through the FFT conversion with received signal, and is divided into the Q section, the corresponding sub-carrier section of then every part.For the output of each sub-carrier section,, can estimate to obtain equivalent channel about each wave beam correspondence according to predefined known symbol.Calculate each wave beam SNR, and pick out the SNR wave beam of maximum for each subcarrier segmentation.Calculate the SNR that this user may reach when transmitting data separately.The user for each sub-carrier section will this section in the sequence number of maximum S R and corresponding wave beam feed back to the base station.But, should be noted that the SNR when calculating this user transmits data separately in this sub-carrier section, and nonessential step, the facility during only for power division.Also can in the power division step, be adjusted accordingly.In addition, the present invention is not limited to the quantization encoding mode for the SNR that will feed back, and requires accurate as far as possible.In addition, in order to realize feeding back more efficiently, can adopt the Best_M feedback, promptly feed back the relevant information of the sub-carrier section of M SNR maximum, can point out the sub-carrier section sequence number this moment as required in feedback information.

In described step 4: for each subcarrier segmentation, the base station is according to the SNR information that the user fed back, with user's descending.Select the user of SNR maximum to add the dispatched users collection, and the pairing adaptive wave beam of this user is added scheduling wave beam collection.After each circulation in, under the unappropriated prerequisite of adaptive wave beam, select the user of SNR maximum to attempt adding the dispatched users collection, check constraints.So maximum circulation N _tAfter-1 time, relatively system can obtainable maximum stream flow when different user is counted, and therefrom selects to make the dispatched users collection of flow system flow maximum and beam configuration that adapts and power allocation scheme.The quick greedy method based on ordering as referred to herein that Here it is.Each sub-carrier section can independently be carried out the user and be selected and power division.Described constraints is meant, carries out optimal power allocation on definite user's collection, the allocation proportion of its allocation result whether zero to 1 between (not comprising end points).The condition that withdraws from above-mentioned circulation is circulation N _tAfter-1 time, promptly all distributed the user on each wave beam, perhaps allocation result does not satisfy constraints in certain once circulates.

In described step 5: power division will be carried out according to power allocation scheme again by the 4th data load that goes on foot the dispatched users of determining to corresponding wave beam in the base station, be loaded into each sub-carrier section, launch via antenna by the IFFT conversion.

In described step 6: each dispatched users receives the data-signal that send base station, through the FFT conversion and with received signal according to the subcarrier segmentation, and utilize orthogonality between wave beam, cross other users' of elimination information, obtain this user's oneself downlink data.

Particularly, below provide more theoretical analysis in detail.

(1) signal processing of OFDM subcarrier segmentation

The segmentation of OFDM subcarrier is that the whole N of an OFDM subcarrier is divided into the Q section fifty-fifty, and every section comprises R continuous sub-carriers.Suppose on channel all subcarriers in same sub-carrier section identical, and different on the subcarrier of different sub carrier section.Generate the beam set w of quadrature independently for each sub-carrier section _q=[w _{Q, 1}..., w _{Q, Nt}].For each sub-carrier section, with known symbol s _iAfter being loaded on each wave beam, system is being output as on each subcarrier on this sub-carrier section

Suppose that the user can receive ofdm signal entirely truely, and received signal is divided into the Q group according to the mode of launching, the average received signal of user k on q sub-carrier section is the average of each subcarrier on this sub-carrier section, its received signal note can be made h _{Q, k}

Receive respectively and detect at the signal of receiving terminal, utilize the orthogonality between known symbol, can learn the equivalent channel h of each wave beam by training for each sub-carrier section _{Q, k}w _i, and can calculate the SNR of received signal thus.Select maximum SNR, and be used for the SNR of estimating user when sub-carrier section q transmits data separately, concrete grammar is the power ‖ h with equivalent channel _{Q, k}w _{Q, i}‖ ²Divided by noise average power σ ², i.e. ‖ h _{Q, k}w _{Q, i}‖ ²/ σ ²This result will be used for user's scheduling.

Be located in q the subcarrier segmentation, user k is scheduled, and distributes and adopt i wave beam.Distributing the ratio of power is the p of this segmented power _kIn formal transmission data, the received signal of user k is:

$y_{q,k}=h_{q,k}*\stackrel{N_t}{\underset{i=1}{\mathrm{\Σ}}}\sqrt{P_{q,k}}{w}_{q,i}{s}_i+n_{q,k}---\left(1\right)$

Utilization estimates the equivalent channel of each wave beam, and the orthogonality between wave beam, can be with non-object beam elimination, thus obtain the data of user k oneself:

$y_{q,k}=\sqrt{P_{q,k}}{h}_{q,k}{w}_{q,i}{x}_k+n_{q,k}---\left(2\right)$

Noise average power is σ ², user's received signal to noise ratio is P _k/ σ ², note is P _kγ _kIf do not particularly point out, SNR that this paper carries is based on the SNR of this form, and scheduling that is proposed and power distribution method all carry out in the segmentation of some subcarriers.

(2) determine the power division of user under collecting

Suppose that transmitting terminal is N _tAntenna system can form N _tIndividual orthogonal beams.And supposition has been chosen n user as dispatched users (n≤N _t), the adaptation wave beam that each user selects has nothing in common with each other.Adopt the orthogonal frequency domain Filtering Processing, the SNR of k user feedback is γ _k, the power of distribution is p _kAnd can suppose j user's SNR value γ _j, γ is arranged _j＜γ _i(i＜j).If adopted enough good coded system, make each user's flow can reach log ₂(1+p _kγ _k).Power distribution method can be expressed as following optimization problem:

$\mathrm{Max}.f_n\left(p\right)=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\log }_2(1+p_i{\mathrm{\γ}}_i)$

$s.p.\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{p}_i=1$

p _i＞0，p _i＜1(i＝1，2，...，n)(3)

The result of optimal power allocation is

If satisfy constraints p _i＞0, p _i＜1 (i=1,2 ..., n) then, think that power division is successful, this user's group can be dispatched simultaneously, and The above results is an optimal result, and the target function optimal value of this moment is:

$f_{n,\max }\left(p^{*}\right)=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\log }_2\left(\frac{{\mathrm{\λ}}_i}{n}(1+\underset{j=1}{\overset{n}{\mathrm{\Σ}}}\frac{1}{{\mathrm{\γ}}_j})\right)={\log }_2\underset{i=1}{\overset{n}{\mathrm{\Π}}}\frac{{\mathrm{\γ}}_i}{n}(1+\underset{j=1}{\overset{n}{\mathrm{\Σ}}}\frac{1}{{\mathrm{\γ}}_j})---\left(4\right)$

Otherwise, the power division failure, this group user cannot be dispatched simultaneously.

Satisfying p _i＞0, p _i＜1 (i=1,2 .., under situation n), if keep n-1 user constant, wherein any one user's SNR is big more, and target function value is that system's total flow is big more.

The analysis constraint condition can obtain following 4 relational expressions:

If therefore for γ _nP is arranged _n≤ 0, then for all γ _{N '}＜γ _n, the person has p _{N '}≤ 0.

$\left(c\right),i<n;p_i>0\&DoubleLeftRightArrow;\frac{n}{{\mathrm{\&gamma;}}_i}-1-\underset{j=1}{\overset{n-1}{\mathrm{\&Sigma;}}}\frac{1}{{\mathrm{\&gamma;}}_j}<\frac{1}{{\mathrm{\&gamma;}}_n}.$

$\left(d\right),i=n;p_n<1\&DoubleLeftRightArrow;1+\underset{j=1}{\overset{n-1}{\mathrm{\&Sigma;}}}\frac{1}{{\mathrm{\&gamma;}}_j}-n<\frac{n-1}{{\mathrm{\&gamma;}}_n}.$

By recursion method, can prove $n-1+\frac{n}{{\mathrm{\&gamma;}}_i}-\underset{j=1}{\overset{n-1}{\mathrm{\&Sigma;}}}\frac{1}{{\mathrm{\&gamma;}}_j}>0.$

According to relational expression (a) and (b), can obtain

Conclusion 1:

For the power distribution algorithm that comprises n user, nth user's SNR satisfies γ _n＜γ _i(i＜n).Under the situation that n-1 user is constant before maintenance, if nth user's power division value p _nCan not satisfy p _n＞0 or p _i＜1 (i＜n), then adopt the SNR value less than γ _nThe user correspondingly can not satisfy p as the nth user arbitrarily _n＞0 and p _i＜1 (i＜n).

Utilization is similar to the method for proof of conclusion 1, can prove that (c) (d) sets up, so can obtain

Conclusion 2:

If for the power distribution algorithm power division success that comprises n-1 user, i.e. p _i＞0, p _i＜1 (i=1,2 ..., n-1).Then for the power distribution algorithm that comprises n user, if nth user's SNR satisfies γ _n＜γ _i(i＜n), then p must be arranged _i＞0 (i＜n) and p _n＜1 (i=n).

The quick greedy algorithm based on ordering that this paper proposed carries out user's scheduling based on the associating optimal power allocation just is being based on determines optimal power allocation and above 2 conclusions of user under collecting.

(3) based on the quick greedy algorithm that sorts

Entire method is divided into N _tStep.The first step is selected the user of maximum S R, and note system total flow is f ₁In the n step, in the non-selected user of corresponding wave beam, the user of search SNR maximum attempts carrying out power division.γ is obviously arranged _n＜γ _i(i＜n), then necessarily satisfy constraints p _i＞0 (i＜n) and p _n＜1 (i=n) (conclusion 2).Check constraints p _n＞0 and p _i＜1 (i＜n),, then finish (, not needing to reattempt the littler user of SNR value) according to conclusion 1 if can not satisfy simultaneously; If can satisfy this two constraintss, the user that this step is selected just can dispatch, and the note flow system flow is f _nIf carried out the m step altogether, compare f ₁, f ₂..., f _mSize, select the group scheduling user group of maximum system flow, and adopt its beam allocation and power division.

Quick greedy algorithm step based on ordering of the present invention is as follows:

(1) with all users according to the SNR descending.According to SNR from big to small, user's sequence number note is done 1,2 ... K.(K is a total number of users).

(2) establish n=1, the user who selects the SNR maximum is as dispatched users, and setting search user sequence number k=1 writes down its adaptive wave beam, record flow f (1).Make n=2.

(3) if n＞N _tJump to step (6), otherwise make k=k+1, set next search subscriber.

(4) if k user's adaptive wave beam is not used, trial adds the dispatched users collection with this user, enters step (5), attempts carrying out power division; Otherwise jump to step (6).

(5) attempt carrying out power division, if the power division success is write down this group scheduling user and collected act_user (n), power division and wave beam and flow f (n).And make n=n+1, and return step (3).If power division is unsuccessful, enter step (6).

(6) maximum among the search f (n) is dispatched corresponding dispatched users collection act_user (n) and power allocation scheme.

Quick greedy algorithm based on ordering of the present invention is to search in an orderly manner, and total hunting zone is total number of users to the maximum.To power division p _nJudgement adopts is the method for comparison, rather than recomputate.In addition, because conclusion 1 and conclusion 2, above-mentioned greedy algorithm has further dwindled the hunting zone, has reduced searching times.So it is N that average each time slot of above-mentioned greedy algorithm is attempted the number of times of user's pairing and power division _t-1.

Provide a concrete downlink honeycomb system parameter configuration below, set forth the specific embodiment of the present invention.Need to prove that the parameter in the following example is not appreciated that restriction generality of the present invention.

Fig. 1 shows the schematic block diagram according to base station 100 of the present invention.With reference to figure 1, base station 100 comprises: wave beam generation unit 110, data load unit 120, emitter 130, receiving system 140, scheduling and power distributing unit 150, and user data cache unit 160.

Wave beam generation unit 110 is used to each subcarrier segmentation to generate the beam set of quadrature randomly, is used for loading data.

When data load unit 120 begins at every frame,, detect for the user for wave beam loads hadamard matrix; At data transfer phase, from user data cache unit 160, obtain the data of dispatched users, and carry out power division according to the power distribution result of scheduling and power distributing unit 150, be loaded on the corresponding wave beam.

Emitter 130 is used for being modulated to each sub-carrier section with coming from wave beam data load unit 120, that loaded data (perhaps hadamard matrixs) by methods such as IFFT conversion, launches by radio-frequency head.

Receiving system 140 obtains baseband signal by the radio-frequency head received signal by demodulation, isolates the signal of each sub-carrier section.

Scheduling and power distributing unit 150 bases come from receiving system 140, by the channel condition information of user feedback, employing is dispatched based on the quick greedy algorithm of ordering, obtain the dispatched users of each wave beam on each sub-carrier section, and corresponding power allocation scheme.

User's downlink data is preserved in user data cache unit 160, calls when being ready for sending for data load unit 120.

Fig. 2 shows the schematic block diagram according to travelling carriage 200 of the present invention.With reference to figure 2, travelling carriage 200 involved in the present invention comprises: receiving system 230, Data Detection unit 220, feedback information generation unit 210, emitter 240, and user data cache unit 260.

Receiving system 230 receives the signal that is sent by base station 100 (particularly, emitter 130), isolates the data of each sub-carrier section, and is sent to 220 detections of Data Detection unit.

Data Detection unit 220 by the orthogonality of hadamard matrix, detects the equivalent channel of each wave beam at the wave beam transfer phase, and generates feedback information by the SNR estimation unit; At data transfer phase, the orthogonality by each wave beam detects user data, delivers to user data cache unit 260.

Equivalent channel on each wave beam that feedback information generation unit 210 detects according to Data Detection unit 220, estimate the SNR when each wave beam transmits separately, and pick out the wave beam that makes the SNR maximum on each sub-carrier section, and corresponding wave beam sequence number and maximum S R value handled, feed back to base station 100 by emitter 240.

Emitter 240 feeds back to base station 100 with the feedback information that feedback information generation unit 210 generates by up channel.

Document with reference to the 3GPP tissue: TR 25.814 V7.1.0, the simulation parameter configuration of one group of downlink honeycomb system that " Physical LayerAspects for Evolved UTRA " (physical layer specification that the universal mobile telecommunications system of evolution and continental rise radio insert) provides, as follows:

The parameter of downlink honeycomb system	Be provided with
		Cellular system model and layout	Single subdistrict
User distribution	Evenly distribute at random
		Number of users in the sub-district	??4，8，16，32，48，64
User moving speed V	??3km/h
		User's reception antenna number	??1
The base station transmit antennas number	??4
		System's average SNR	??0db
Central authorities' carrier frequency	??2GHz
		Bandwidth	??1.25MHz
Subcarrier spacing	??15kHz
		Sub-carrier number	??128
Sample frequency	??1.92MHz
		The duration of a physical frame	??10ms
The duration of a subframe	??0.5ms
		The OFDM symbolic number that subframe comprised	??7
The expense of beam equivalent Channel Detection and feedback SNR	10% (14 OFDM symbol times)

In addition, following parameter is adopted in segmentation for the OFDM subcarrier:

The subcarrier segments	??8
		Per minute cross-talk carrier number	??16

The Suburban Macro channel parameter in the corresponding employing of the time domain of channel 6 footpaths, specific as follows:

	Postpone (ns)	Relative power (dB)
			Path 1	??0.0	??0
Path 2	??137.5	??-8.50
			Path 3	??62.5	??-7.28
Path 4	??400.0	??-8.45
			Path 5	??1387.5	??-14.65
Path 6	??2825.0	??-26.43

The system channel modeling can be with reference to following document: Yahong Rosa Zheng, Deng " Simulation Models With Correct Statistical Properties forRayleigh Fading Channels ", IEEE TRANSACTION ON COMMUNICATIONS, June 2003 (" the rayleigh fading channel simulation model of correct statistical property ").

Fig. 3 shows the flow chart according to multi-user dispatching method of the present invention, Fig. 4 show according to of the present invention, based on the flow chart of quick greedy algorithm of ordering.Be segmented into example with 8 users, first OFDM subcarrier, concrete operations of the present invention be described below in conjunction with Fig. 3 and Fig. 4:

(1) step S310: 100 sides in the base station, based on cell/section and channel model, create 4 dimension wave beam (N of 4 quadratures for first subcarrier segmentation _t=4), form beam set W:

Wave beam 1	Wave beam 2	Wave beam 3	Wave beam 4
				??-0.0247+0.2919i	??-0.1946-0.6350i	??-0.3063+0.1353i	??-0.5701-0.1897i
??0.0844-0.8609i	??-0.1487-0.1310i	??0.0992+0.2708i	??-0.1245-0.3373i
				??-0.0885+0.3111i	??-0.3019+0.5020i	??-0.1030+0.3730i	??0.0611-0.6314i
??-0.1858+0.1636i	??0.2654-0.3257i	??0.3570+0.7263i	??0.3043+0.1211i

A wave beam is shown in each tabulation, and its power is 1.In order to keep total emission power is 1, the transmitting power of each wave beam can be adjusted into

Be 4 wave beams loading hadamard matrixs in first sub-carrier section, adopt 4 OFDM symbols to go out from antenna transmission.Hadamard matrix is:

??1	??1	??1	??1
				??1	??-1	??1	??-1
??1	??1	??-1	??-1
				??1	??-1	??-1	??1

Channel matrix on first subcarrier is:

	Antenna 1	Antenna 2	Antenna 3	Antenna 4
					The user 1	??-0.2492+0.5670i	??0.8516+0.1050i	??0.5725+0.7770i	??0.6997-0.9803i
The user 2	??-0.0718-0.2413i	??-0.4616-0.2159i	??-0.9858-1.3564i	??-0.7469+0.7743i
					The user 3	??-0.2366-0.0938i	??0.1609+0.8091i	??0.2437+0.3050i	??-0.0094-0.7362i
The user 4	??1.6180+1.0559i	??0.0326+0.3530i	??-0.2993+1.0091i	??0.6428-0.4650i
					The user 5	??-0.3497+0.2264i	??0.4354+0.5426i	??0.2056+2.5766i	??-0.7876-0.8269i
The user 6	??0.1933+0.2222i	??-0.6573+0.0437i	??-0.4287-0.4704i	??-1.3798+0.8349i
					The user 7	??0.6416-0.9796i	??-0.1549+0.3074i	??-0.3120-0.6397i	??-0.0011+0.0975i
The user 8	??1.4485+0.3035i	??0.1346-0.7619i	??-0.4928+0.6503i	??0.1877+1.5633i

(2) step S320:, suppose that receiver can correctly detect data from sub-carrier section, and obtain the equivalent channel of each wave beam by hadamard matrix in travelling carriage 200 sides.Travelling carriage 200 is from one group of corresponding sub-carrier section monitoring and detect the wave beam that this cell/section base station sends, and in the emulation, output signal is:

$y_{k,i}=h_{q,k}*\frac{1}{\sqrt{N_t}}\underset{i=1}{\overset{N_t}{\mathrm{\&Sigma;}}}{w}_{q,i}{s}_i+n_{q,k}$

$\&RightArrow;\frac{1}{\sqrt{N_r}}{h}_k{w}_i+n_i$

Average received signal to noise ratio on each subcarrier of first sub-carrier section is

	Wave beam 1	Wave beam 2	Wave beam 3	Wave beam 4
					The user 1	??0.0214	??0.0355	??0.2177	??0.6515
The user 2	??0.2507	??0.1962	??0.0373	??0.2093
					The user 3	??0.0508	??0.1316	??0.0009	??0.1899
The user 4	??0.0876	??0.9257	??0.0206	??0.2317
					The user 5	??0.1463	??0.7938	??0.1368	??0.7793
The user 6	??0.0611	??0.2648	??0.0176	??0.1166
					The user 7	??0.1797	??0.0873	??0.0089	??0.0876
The user 8	??0.379	??0.3436	??0.4875	??0.1091

From the SNR (signal noise ratio) of each wave beam of estimating, pick out the wave beam of SNR maximum.This SNR be multiply by 4, estimate the SNR of this user when first sub-carrier section is communicated by letter separately.The estimation SNR that travelling carriage 200 feeds back for the selection situation and the transfer of data of wave beam:

The user	??SNR	The wave beam sequence number
			??1	??2.6059	??4
??2	??1.0027	??1
			??3	??0.7598	??4
??4	??3.7027	??2
			??5	??3.1751	??2
??6	??1.0591	??2
			??7	??0.719	??1
??8	??1.9498	??3

If adopt the feedback method of best M, then travelling carriage needn't feed back for each sub-carrier section, but from 16 sub-carrier section, the M that chooses the SNR maximum is individual, feeds back.Feed back SNR, wave beam sequence number except needs during feedback, also need to feed back the sequence number of sub-carrier section.If M=3, then for each user, feedack is the interior wave beam sequence number of sequence number, SNR and corresponding sub-carrier section of three sub-carrier section of SNR maximum.

(3) step S330: 100 sides in the base station, the time of 10 OFDM symbols is waited in base station 100, collects user feedback.According to the SNR of user feedback and the wave beam sequence number that is complementary, base station 100 is by determining the dispatched users collection based on the quick greedy algorithm of ordering, and the power allocation scheme of the adaptive wave beam of dispatched users.Fig. 4 has specifically illustrated the flow chart based on the quick greedy algorithm of ordering.

At first, with user's feedback information according to SNR ordering (step S3310):

Sequence number	??SNR	The user	The wave beam sequence number
				??1	??3.7027	??4	??2
??2	??3.1751	??5	??2
				??3	??2.6059	??1	??4
??4	??1.9498	??8	??3
				??5	??1.0591	??6	??2
??6	??1.0027	??2	??1
				??7	??0.7598	??3	??4
??8	??0.719	??7	??1

Step S3320: with sequence number is that 1 user (user 4) adds the dispatched users collection, is that 2 wave beam adds scheduling wave beam collection with the wave beam sequence number.Recording dispatching speed f (1).

Step S3330: not: n=2 is not more than N _t=4.

Step S3340～S3350: the detection sequence number is 2 user (user 5).Because its adaptive wave beam (wave beam sequence number 2) is occupied, skips (step S3350: be).

Step S3340～S3350: the detection sequence number is 3 user (user 1).Because the wave beam sequence number of its adaptive wave beam is 4, unoccupied (step S3350: not).Step S3360: can attempt user 1 is added the dispatched users collection, be that 4 wave beam adds scheduling wave beam collection with the wave beam sequence number, and power distribution result is:

	Wave beam 1	Wave beam 2	Wave beam 3	Wave beam 4
					Scheduling power	??0	??0.5568	??0	??0.4432

Step S3370: be: satisfy constraints (that is, each allocation result (power division ratio) of dispatching power (does not comprise end points) between 0 to 1), therefore be allocated successfully.Step S3380: record allocation result, recording dispatching speed f (2).

Step S3330: not: n=3 is not more than N _t=4.

Step S3340～S3350: the detection sequence number is 4 user (user 8).Because its adaptive wave beam is a wave beam 3, unoccupied (step S3350: not).Step S3360: can attempt user 8 is added the dispatched users collection, wave beam 3 is added scheduling wave beam collection, power distribution result is:

	Wave beam 1	Wave beam 2	Wave beam 3	Wave beam 4
					Scheduling power	????0	?0.4522	?0.2094	?0.3385

Step S3370: be: satisfy constraints (that is, each allocation result (power division ratio) of dispatching power (does not comprise end points) between 0 to 1), therefore be allocated successfully.Step S3380: record allocation result, recording dispatching speed f (3).

Step S3330: not: n=4 is not more than N _t=4.

Step S3340～S3350: the detection sequence number is 5 user (user 6).Because its adaptive wave beam (wave beam sequence number 2) is occupied, skips (step S3350: be).

Step S3340～S3350: the detection sequence number is 6 user (user 2).Because its adaptive wave beam is a wave beam 1, unoccupied (step S3350: not).Step S3360: can attempt user 1 is added the dispatched users collection, wave beam 1 is added scheduling wave beam collection, power distribution result is:

	Wave beam 1	Wave beam 2	Wave beam 3	Wave beam 4
					Scheduling power	0.5209	?0.4073	?0.2781	-0.2063

Step S3370: not: do not satisfy constraints (that is, the allocation result (power division ratio) of at least one scheduling power (does not comprise end points) not between 0 to 1), therefore distribute and get nowhere, also do not reattempt other power division combination.

Step S3390: gather the scheduling rates result:

	????f(1)	????f(2)	????f(3)	????f(4)
					Scheduling rates	??2.2335	??2.7220	??2.8253	????0

Scheduling result, dispatched users and scheduling power when therefore selecting three users for use:

	Wave beam 1	Wave beam 2	Wave beam 3	Wave beam 4
					Dispatched users	????0	?4	?8	?1
Scheduling power	????0	?0.4522	?0.2094	?0.3385

(4) step S340: base station 100 is carried out the data load of each dispatched users adaptive wave beam to this dispatched users power division according to power distribution result, and is sent to each user's travelling carriage 200.The transmission rate of first sub-carrier section can reach 16 * 15k * 2.8253bps.

(5) step S350: user's travelling carriage 200 filters out data separately by correct subcarrier segmentation, and carries out subsequent treatment.With the flow addition that each sub-carrier section obtains, the total flow that slot sytem can be realized in the time of can obtaining this.

Communication system for adopting based on the quick greedy algorithm of ordering in order to investigate the performance of its computation complexity and flow system flow, compares following method:

ES_PA (prior art): adopt exhaustive search associating optimal power allocation.In all possible user's pairing, attempt carrying out optimal power allocation, and select scheduling and the power allocation scheme that makes the flow system flow maximum.

ES_avg_PA (prior art): adopt exhaustive search associating average power allocation.In all possible user's pairing, attempt averaging power division, and select scheduling and the power allocation scheme that makes the flow system flow maximum.

Th_avg_PA (prior art): thresholding-average power allocation.Adopt 1 Signal Interference and Noise Ratio SINR thresholding, each user finds out the wave beam that makes the SINR maximum, if maximum SINR surpasses default thresholding, feeds back 1 bit 1 and optimum beam sequence number, otherwise feeds back 1 bit 0 and optimum beam sequence number.The base station is wave beam random choose from feedback user that feedback is arranged, and is the wave beam random choose user from all users who does not have user feedback, and carries out average power allocation.

IGS_PA (the present invention): adopt quick greedy search associating optimal power allocation based on ordering.Employing is attempted carrying out optimal power allocation, and is selected scheduling and the power allocation scheme that makes the flow system flow maximum based on the quick greedy search of ordering.

IGS_avg_PA (the present invention): adopt quick greedy search associating average power allocation based on ordering.Employing is attempted averaging power division, and is selected scheduling and the power allocation scheme that makes the flow system flow maximum based on the quick greedy search of ordering.

Below provided the comparison of algorithm complex, foundation relatively is on average in each OFDM subcarrier segmentation, the number of times of average user that each time slot is attempted pairing and power division, wherein for the Th_avg_PA algorithm, because the base station is wave beam random choose from feedback user that feedback is arranged, be the wave beam random choose user from all users who does not have user feedback, so this parameter identification is "-":

Number of users	??ES_PA	??IGS_PA	??ES_avg_PA	??IGS_avg_PA	?Th_avg_PA
						??8	??56.6809	??2.5778	??56.6809	??2.6037	??-
??16	??488.4918	??2.9559	??488.4918	??2.9605	??-
						??32	??5674	??3	??5674	??3	??-
??48	??2578.4	??3	??2578.4	??3	??-
						??64	??76662	??3	??76662	??3	??-

As can be seen, adopting the number of times of average each time slot trial user's pairing of the quick greedy dispatching algorithm based on ordering according to the present invention and power division is N _t-1, and its simulation time is less than exhaust algorithm far away, has reduced the complexity of system significantly.

Relatively adopt according to of the present invention based on the system of quick greedy dispatching algorithm of ordering and the flow system flow of other system, bandwidth carried out normalized:

Number of users	??ES_PA	??IGS_PA	??ES_avg_PA	??IGS_avg_PA	??Th_avg_PA
						??8	??2.8736	??2.8736	??2.8389	??2.8389	??2.469
??16	??3.4838	??3.4838	??3.4427	??3.4427	??2.932
						??32	??3.8855	??3.8855	??3.8495	??3.8495	??3.39
??48	??4.2733	??4.2733	??4.239	??4.239	??3.652
						??64	??4.3303	??4.3303	??4.3023	??4.3023	??3.834

As can be seen, adopt the algorithm of optimal power allocation all to be better than the algorithm that adopts average power allocation.This shows, positive effect is arranged for improving flow system flow though power distribution algorithm can increase a spot of computation complexity.In two kinds of algorithms that adopt optimal power allocation, employing is according to the algorithm that distributes based on the quick greedy search joint Power of ordering of the present invention, made full use of the characteristic of system, when reducing complexity, for the not loss of flow system flow aspect, can reach and exhaust algorithm flow system flow much at one.More after a little while, adopt average system flow that analog feedback SNR method realized at low SNR and number of users far above adopting limit bit to quantize the method for feedback SNR.

Therefore, the random wave bundle that the present invention proposes forms the multi-user dispatching method of system combined power division, has utilized the characteristic of the wave beam formation system of quadrature multi-beam, has realized the higher system flow.By adopting the signal processing method with the segmentation of OFDM subcarrier, the frequency domain that strengthens channel response rises and falls; By adopting the beam set of quadrature, eliminated the interference between the different beams, realized the independent detection of a plurality of equivalent channel.The user only need feed back SNR and wave beam sequence number, thereby has reduced user uplink feedback data amount.By quick greedy method, can finish user's scheduling and power division with lower algorithm complex based on ordering.Especially along with the increase of number of users, time cost does not increase; Even number of transmit antennas increases, the time cost of multi-user dispatching method proposed by the invention also only is a linear growth.So the present invention has realized the higher system flow in the algorithm complex that significantly reduces user's scheduling and power division, have between spectrum reuse coefficient height, user and base station feedback less, realize simply and be beneficial to and advantage such as practice.

The description of front has just provided the preferred embodiments of the present invention, and will limit the present invention anything but.Therefore, any modification of making within spirit of the present invention and principle, replacement, improvement etc. all should fall within the scope of the invention.

Claims (25)

1. a multi-user dispatching method is applied to random wave bundle and forms in the OFDM ofdm system, and described multi-user dispatching method may further comprise the steps:

The base station is the segmentation of OFDM subcarrier, and is each sub-carrier section, creates N independently _tIndividual orthogonal beams forms the beam set of each sub-carrier section, wherein N _tIt is natural number;

At the beam set of each sub-carrier section,

Each travelling carriage determines to have the wave beam of peak signal noise ratio SNR, and to the wave beam identification information of base station feedback SNR information and described wave beam;

The travelling carriage that the base station is selected to have maximum S R in having carried out all travelling carriages of feedback information adds the dispatched users collection, and the pairing adaptive wave beam of this travelling carriage is added scheduling wave beam collection;

For other travelling carriages except travelling carriage with maximum S R, under the unappropriated prerequisite of corresponding adaptive wave beam, the travelling carriage that the base station is selected to have maximum S R successively attempts adding the dispatched users collection, and attempt corresponding adaptive wave beam is added scheduling wave beam collection, check whether dispatched power distribution result satisfies predetermined constraint conditions;

If each the trial all succeedd, promptly each dispatched power distribution result all satisfies predetermined constraint conditions, and then the base station is attempted N at most _t-1 time,, then no longer carry out follow-up trial if certain attempts not success;

The base station selected dispatched users collection of flow system flow maximum, the beam configuration that adapts and the power distribution result of making.

2. multi-user dispatching method according to claim 1 is characterized in that also comprising:

The base station is loaded into each beam set on the corresponding OFDM sub-carrier section, goes out from antenna transmission.

3. multi-user dispatching method according to claim 1 is characterized in that also comprising:

This sub-district or beam set that sector base stations sent are monitored and detected to each travelling carriage from each OFDM sub-carrier section, estimates the SNR of each wave beam in the described beam set.

4. multi-user dispatching method according to claim 3 is characterized in that:

Each travelling carriage is selected described wave beam with maximum S R from the SNR of each wave beam of estimating.

5. multi-user dispatching method according to claim 4 is characterized in that:

With the wave beam number N in described maximum S R and the described beam set _tMultiply each other, obtain maximum simple beam SNR, and replace maximum S R, feed back described maximum simple beam SNR.

6. multi-user dispatching method according to claim 1 is characterized in that:

In described OFDM subcarrier division step, the OFDM subcarrier is equally divided into the Q section, Q is the integer greater than 1.

7. according to the described multi-user dispatching method of one of claim 1～6, it is characterized in that:

Wave beam number N in the beam set of each sub-carrier section _tMutually the same, and beam set has nothing in common with each other.

8. according to the described multi-user dispatching method of one of claim 1～6, it is characterized in that:

In all sub-carrier section, M had the sub-carrier section of maximum S R before each travelling carriage was determined, and only had the SNR information and the wave beam identification information of the wave beam of maximum S R in this M of base station feedback sub-carrier section.

9. multi-user dispatching method according to claim 8 is characterized in that:

The wave beam identification information that has the wave beam of maximum S R in the described M sub-carrier section comprises the sign of sub-carrier section and the sign of wave beam.

10. according to the described multi-user dispatching method of one of claim 1～9, it is characterized in that:

Described predetermined constraint conditions is: dispatched power distribution result does not comprise 0 and 1 between 0 and 1.

11., it is characterized in that according to the described multi-user dispatching method of one of claim 1～9:

The base station is according to selected dispatched users collection, the beam configuration that adapts and power distribution result, and the down user data of each travelling carriage is loaded into the adaptive wave beam of this travelling carriage, carries out power division according to power distribution result, and sends to each travelling carriage.

12. multi-user dispatching method according to claim 10 is characterized in that:

Each travelling carriage is according to correct subcarrier segmentation and utilize orthogonality between wave beam, filters the down user data of removing other travelling carriages, obtains the down user data of this travelling carriage.

13. a multi-user dispatching device is applied to random wave bundle and forms in the OFDM ofdm system, described multi-subscriber dispatching loading amount comprises:

The wave beam generation unit is used for the segmentation of OFDM subcarrier, and is each sub-carrier section, creates N independently _tIndividual orthogonal beams forms the beam set of each sub-carrier section, wherein N _tIt is natural number;

Scheduling and power distributing unit are used for the beam set at each sub-carrier section,

The travelling carriage of selecting to have peak signal noise ratio SNR in having carried out all travelling carriages of feedback information adds the dispatched users collection, and the pairing adaptive wave beam of this travelling carriage is added scheduling wave beam collection;

For other travelling carriages except travelling carriage with peak signal noise ratio SNR, under the unappropriated prerequisite of corresponding adaptive wave beam, the travelling carriage of selecting successively to have maximum S R attempts adding the dispatched users collection, and attempt corresponding adaptive wave beam is added scheduling wave beam collection, check whether dispatched power distribution result satisfies predetermined constraint conditions;

If each the trial all succeedd, promptly each dispatched power distribution result all satisfies predetermined constraint conditions, then attempts N at most _t-1 time,, then no longer carry out follow-up trial if certain attempts not success;

Selection makes the dispatched users collection of flow system flow maximum, the beam configuration that adapts and power distribution result.

14. multi-user dispatching device according to claim 13 is characterized in that also comprising:

Data load and transmitter unit are used for each beam set is loaded into corresponding OFDM sub-carrier section, go out from antenna transmission.

15. multi-user dispatching device according to claim 13 is characterized in that:

Described wave beam generation unit is equally divided into the Q section with the OFDM subcarrier, and Q is the integer greater than 1.

16., it is characterized in that according to the described multi-user dispatching device of one of claim 13～15:

Wave beam number N in the beam set of each sub-carrier section _tMutually the same, and beam set has nothing in common with each other.

17., it is characterized in that according to the described multi-user dispatching device of one of claim 13～16:

Described predetermined constraint conditions is: dispatched power distribution result does not comprise 0 and 1 between 0 and 1.

18. a base station comprises according to the described multi-user dispatching device of one of claim 1～17.

19. base station according to claim 18 is characterized in that also comprising:

User data loads and transmitter unit, be used for according to selected dispatched users collection, the beam configuration that adapts and power distribution result, the down user data of each travelling carriage is loaded into the adaptive wave beam of this travelling carriage, carries out power division according to power distribution result, and send to each travelling carriage.

20. an information feedback device is applied to random wave bundle and forms in the OFDM ofdm system, forms in the OFDM ofdm system at described random wave bundle, the OFDM subcarrier is by segmentation, and is each sub-carrier section, creates N independently _tIndividual orthogonal beams forms the beam set of each sub-carrier section, wherein N _tBe natural number, described information feedback device comprises:

Receive and detecting unit, be used for monitoring and detect this sub-district or beam set that sector base stations sent, estimate the signal noise ratio SNR of each wave beam in the described beam set from each OFDM sub-carrier section; And

Feedback information generates and transmitter unit, is used for the beam set at each sub-carrier section, determines to have the wave beam of maximum S R, and to the wave beam identification information of base station feedback SNR information and described wave beam.

21. an information feedback device is applied to random wave bundle and forms in the OFDM ofdm system, forms in the OFDM ofdm system at described random wave bundle, the OFDM subcarrier is by segmentation, and is each sub-carrier section, creates N independently _tIndividual orthogonal beams forms the beam set of each sub-carrier section, wherein N _tBe natural number, described information feedback device comprises:

Receive and detecting unit, be used for monitoring and detect this sub-district or beam set that sector base stations sent, estimate the signal noise ratio SNR of each wave beam in the described beam set from each OFDM sub-carrier section; And

Feedback information generates and transmitter unit, is used for the beam set at each sub-carrier section, determines to have the wave beam of maximum S R, with the wave beam number N in described maximum S R and the described beam set _tMultiply each other, obtain maximum simple beam SNR, and to the wave beam identification information of maximum simple beam SNR information of base station feedback and described wave beam.

22., it is characterized in that according to claim 20 or 21 described information feedback devices:

In all sub-carrier section, described feedback information generates and transmitter unit determines that preceding M has the sub-carrier section of maximum S R, and only has the SNR information and the wave beam identification information of the wave beam of maximum S R in this M of base station feedback sub-carrier section.

23. information feedback device according to claim 22 is characterized in that:

The wave beam identification information that has the wave beam of maximum S R in the described M sub-carrier section comprises the sign of sub-carrier section and the sign of wave beam.

24. a travelling carriage comprises according to the described multi-user dispatching device of one of claim 20～23.

25. travelling carriage according to claim 24 is characterized in that also comprising:

User data receives and detecting unit, is used for according to correct subcarrier segmentation and utilizes orthogonality between wave beam, filters the down user data of removing other travelling carriages, obtains the down user data of this travelling carriage.

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