CN104868943B - Multiuser MIMO user choosing method based on conditional number - Google Patents

Multiuser MIMO user choosing method based on conditional number Download PDF

Info

Publication number
CN104868943B
CN104868943B CN201510202422.1A CN201510202422A CN104868943B CN 104868943 B CN104868943 B CN 104868943B CN 201510202422 A CN201510202422 A CN 201510202422A CN 104868943 B CN104868943 B CN 104868943B
Authority
CN
China
Prior art keywords
user
selection
temp
norm
alternative
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN201510202422.1A
Other languages
Chinese (zh)
Other versions
CN104868943A (en
Inventor
杜岩
康向兵
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shandong University
Original Assignee
Shandong University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shandong University filed Critical Shandong University
Priority to CN201510202422.1A priority Critical patent/CN104868943B/en
Publication of CN104868943A publication Critical patent/CN104868943A/en
Application granted granted Critical
Publication of CN104868943B publication Critical patent/CN104868943B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0413—MIMO systems
    • H04B7/0452—Multi-user MIMO systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0413—MIMO systems
    • H04B7/0426—Power distribution

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Power Engineering (AREA)
  • Radio Transmission System (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

The present invention relates to a kind of multiuser MIMO user choosing method based on conditional number；The algorithm is according to subscriber channel Frobenius norm κi=| | Hk||F, criterion, which is maximized, with norm selects first user ui；The search set of user is reduced according to the condition of conditional number, so that during next iteration, the maximum user of the system capacity performance made is selected in a lesser set, and then be ensure that the performance of algorithm and reduced the complexity of searching algorithm to a certain extent.The user choosing method structure is simple, and operation, treating capacity are low, and treatment effeciency is high.

Description

Multiuser MIMO user choosing method based on conditional number
Technical field:
The present invention relates to a kind of multiuser MIMO user choosing method based on conditional number, belongs to the skill of wireless communication technique Art field.
Background technique:
In recent years, with the surge of wireless data, requirement of the people for wireless communication is also gradually increased.Multi-antenna technology Also it increasingly attracts people's attention.Multiple-input and multiple-output (multiple-input multiple-output) is multiple by diversity The capacity of communication system is greatlyd improve with technology.Based on multi-input multi-output system, and it is proposed that multi-user's is how defeated Enter multiple output system (MU-MIMO), further improve the capacity of system, and reduce the bit error rate of communication system, with reply People's demand growing to data traffic.Multi-user MIMO system mainly includes three modules:
A, MU-MIMO transmitting terminal (BS) processing module:
The information bit to be transmitted is generated, symbol mapping, radio frequency, IF Modulation and Base-Band Processing are carried out.Main is this Module will carry out precoding to input signal to eliminate existing multi-user interference (MUI) between multi-user, then carry out user The user for needing to dispatch is selected in selection；
B, the OFDM module of MU-MIMO:
This module carries out OFDM processing primarily with respect to previously processed signal and enables adaptive channel environment, reduces The bit error rate, this module are also responsible for the Space Time Coding part from signal to antenna mapping；
C, selecting module:
This module mainly contains selected user's scheduling set, that is to say, that selects inside alternative user set Satisfactory user services.
The application of multiuser MIMO technology, so that space is become one kind can be used for proposing high performance resource, and can increase The coverage area of wireless system greatly meets the performance indicator of next generation mobile communication.
Due to needing there is the interference between user in multi-user MIMO system therefore in transmitting terminal according to user's Channel situation is pre-processed to eliminate the interference between user, this preprocessing process is referred to as precoding.Dirty paper code (Dirty Paper Coding) is optimal pre-coding scheme, because it can reach the capacity of information theory.But in reality Required time and power are limited in the work of border, since its nonlinear subsequent iteration step needs a large amount of calculating, And then need more power losses.So DPC is not applied in practice.Instead it is some better simply linear pre- Encryption algorithm.
However a pre-coding matrix also needs power distribution part, due to the transmission power of transmitting terminal be it is certain, So it is also a problem that how limited power, which goes distribution,.
Existing multi-user MIMO system user selection algorithm or complexity are excessively high, need more power losses, It is that performance is lower, is unable to satisfy technical need.
Term explanation:
Matrix condition number (condition number):
Wherein λmin(A), λmax(A) the minimum and maximum characteristic value of A is respectively indicated.Matrix condition number is for measuring matrix One of similarity estimates.With it is this estimate be measure two matrix volume similarities, it is known that, if two matrixes tend to be similar, The value of their conditional number tends to 0dB, if two matrix dissmilarities, the absolute value of conditional number may much be partial to 0dB.
Interference between user:
Assuming that MU-MIMO transmitting terminal (BS) end is furnished with M root transmitting antenna, each reception end subscriber ui(i indicates User ID) Configure NiRoot receiving antenna, the sum for receiving end subscriber i is Kt, channel is additive white Gaussian noise channel.
Assuming that antenna is sent to user u after treatmentiSignal be xi, signal xiThe channel matrix of process is Hi, letter The Gaussian noise for number being the channel that xi passes through is ni, yiIndicate receiving antenna received signal, then:
yi=HiTixi+Σj≠i,j∈SHiTjxj+ni (1)
Wherein Ti,TjIt is pre-coding matrix, niIt is zero mean Gaussian white noise, set S indicates alternative user set.And Transmitting signal meets power limit E [XXH]≤P.Middle entry Σ in above formulaj≠i,j∈SHjTixjBe exactly other users exist for Family uiInterference.
Block diagonalization algorithm:
Block diagonalization algorithm is mainly the thought for making multi-user interference zero, that is, makes the Σ in formula (1)j≠i,j∈ SHiTjxj=0, it can abridge constraint condition to ask this to solve us.So that following formula is set up
HiTj=0 i ≠ j ∈ S
That is pre-coding matrix TjFall in channel matrix HiNull subspace in.We can by polymer matrix come Simplify above-mentioned solution, it is assumed that polymer matrix
Wherein K is the total number of users selected in family set S.So that TjIt falls in the kernel of above formula.
It maximizes criterion: in the selection process, remaining that the maximized standard of current capacities goes selection user.
According to theoretical proof mathematically, we can acquire a part of pre-coding matrix with singular value decomposition.Into There is the limitation of a rank of matrix when row singular value decomposition, reflection is exactly that transmitting antenna cannot be less than each into actual application The sum of receiving antenna of user, also proved from this point user selection necessity, with for transmitting terminal number of antennas it is limited, and Userbase is usually a very huge set, so effective user's selection algorithm is to ensure that the prerequisite item of volumetric properties Part.
Summary of the invention:
In view of the deficiencies of the prior art, the present invention provides a kind of multiuser MIMO user choosing method based on conditional number； Inventive algorithm reduces the search set of user according to the condition of conditional number so that during next iteration, one compared with It selects the maximum user of the system capacity performance made in small set, and then ensure that the performance of algorithm again to a certain extent Reduce the complexity of searching algorithm.
Technical scheme is as follows:
In the multiuser MIMO user choosing method of the present invention based on conditional number, in order to simplify emulation, we Assuming that each user configuration antenna of equivalent, and the environment of channel is identical, and channel condition be it is known, this point is in the time-division The situation known to channel can be easily realized in multipling channel (TDD).Under the premise of known to the channel condition, it can prove Water-filling algorithm is optimal power allocation scheme, so carrying out power distribution using water-filling algorithm herein.
Multiuser MIMO user choosing method based on conditional number, comprises the following steps that
A, it initializes:
Initialize the parameter in current mimo system；Initialize alternative user setWith selection user's set S=φ；
B, user's set is updated:
Select first user ui, and update the alternative user set and selection user set Computing system capacity C=waterfilling (S)；
C, alternative user setDiminution processing:
To alternative user setDiminution processing,Wherein HSIt is selection user's set User's polymer matrix of S, controling parameter α are empirical；It is user uiChannel matrix；Pass through set of computationsIn it is every The value of a element and the Matrix condition number of selection user's set is gathered to reduce；
Find userAnd calculate temporary system capacity Ctemp=waterfilling (S+ { uj})；
D, loop iteration:
If Ctemp> C, i.e. Δ C=Cgain-Closs> 0 then updates alternative user set, selection user set and system and holds AmountC=Ctemp, and carry out loop iteration next time；
Otherwise, loop iteration next time is directly carried out；
By comparing power system capacity C and temporary system capacity CtempJudge user uiAddition whether system performance is obtained Promotion is arrived；That is if Ctemp> C, user meets condition and can be selected at this time；
E, loop termination；
Step C-D (K-1) secondary backed off after random circulation is repeated, whereinM is transmitting antenna number, and N is each The receiving antenna number of the equivalent of user configuration；This expression formula is the capacity that system can accommodate in the case where BD precoding The upper limit, that is, the above circulation K-1 take second place backed off after random circulation.
It is preferred according to the present invention, in the step A, select first user uiSpecific method be: according to user Channel Frobenius norm κi=| | Hk||F, criterion, which is maximized, with norm selects first user ui。
It is preferred according to the present invention, it is calculated in the step B in power system capacity C, the step C and calculates temporary system appearance Measure CtempMethod be water-filling algorithm.The situation known to channel can be easily realized in time division multiplex channel (TDD)； Under the premise of known to the channel condition, it can prove that water-filling algorithm is optimal power allocation scheme.
It is preferred according to the present invention, in the step C, find userSpecific method be, with maximum norm Method finds userNamely the selection maximum user of norm.
Preferred according to the present invention, in the step C, the value of the controling parameter α is 0.2.
Present invention has an advantage that
1, multiuser MIMO user choosing method of the present invention, the search of user is reduced according to the condition of conditional number Set, so that the maximum user of the system capacity performance made is selected in a lesser set during next iteration, into And it ensure that the performance of algorithm reduces the complexity of searching algorithm to a certain extent；
2, multiuser MIMO user choosing method of the present invention, structure is simple, and operation, treating capacity are low, treatment effeciency It is high.
Detailed description of the invention:
Fig. 1 is the structural schematic diagram of multi-user MIMO system；
Fig. 2 is the comparison of the power system capacity figure of three kinds of multiuser MIMO selection algorithms；
Fig. 3 is the comparison of the algorithm complexity of three kinds of multiuser MIMO selection algorithms.
Specific embodiment:
The present invention is described in detail below with reference to embodiment and Figure of description, but not limited to this.
Embodiment 1,
As shown in Figs. 1-3.
Multiuser MIMO user choosing method based on conditional number, comprises the following steps that
A, it initializes:
Initialize the parameter in current mimo system；Initialize alternative user setWith selection user's set S=φ；
B, user's set is updated:
According to subscriber channel Frobenius norm κi=| | Hk||F, criterion, which is maximized, with norm selects first user ui, And update the alternative user set and selection user setHeld using water-filling algorithm computing system It measures C=waterfilling (S)；
C, alternative user setDiminution processing:
To alternative user setDiminution processing,Wherein HSIt is selection user's set User's polymer matrix of S, controling parameter 0.2 are empirical；It is user uiChannel matrix；Pass through set of computationsIn The value of each element and the Matrix condition number of selection user's set is gathered to reduce；
Find userAnd temporary system capacity C is calculated using water-filling algorithmtemp=waterfilling (S+ {uj})；
D, loop iteration:
If Ctemp> C, i.e. Δ C=Cgain-Closs> 0 then updates alternative user set, selection user set and system and holds AmountC=Ctemp, and carry out loop iteration next time；
Otherwise, loop iteration next time is directly carried out；
By comparing power system capacity C and temporary system capacity CtempJudge user uiAddition whether system performance is obtained Promotion is arrived；That is if Ctemp> C, user meets condition and can be selected at this time；
E, loop termination；
Step C-D (K-1) secondary backed off after random circulation is repeated, whereinM is transmitting antenna number, and N is each The receiving antenna number of the equivalent of user configuration；This expression formula is the capacity that system can accommodate in the case where BD precoding The upper limit, that is, the above circulation K-1 take second place backed off after random circulation.

Claims (1)

1. the multiuser MIMO user choosing method based on conditional number, which is characterized in that comprise the following steps that
A, it initializes:
Initialize the parameter in current mimo system；Initialize alternative user setWith selection user's set S= φ；Select first user uiSpecific method be: according to subscriber channel Frobenius norm κi=| | Hk||F, most with norm Bigization criterion selects first user ui；
B, user's set is updated:
Select first user ui, and update the alternative user set and selection user setS={ ui, Computing system capacity C=waterfilling (S)；The method of computing system capacity C is water-filling algorithm；
C, alternative user setDiminution processing:
To alternative user setDiminution processing,Wherein HSIt is the use for selecting user's set S Family polymer matrix, controling parameter α are empirical；It is user uiChannel matrix；The value of the controling parameter α is 0.2；
Find userAnd calculate temporary system capacity Ctemp=waterfilling (S+ { uj})；Temporary system is calculated to hold Measure CtempMethod be water-filling algorithm；
Find userSpecific method be to find user with the method for maximum normNamely selection norm is maximum User；
D, loop iteration:
If Ctemp> C, i.e. △ C=Cgain-Closs> 0, then update alternative user set, selection user set and power system capacityS={ uj, C=Ctemp, and carry out loop iteration next time；
Otherwise, loop iteration next time is directly carried out；
E, loop termination；
Step C-D (K-1) secondary backed off after random circulation is repeated, whereinM is transmitting antenna number, and N is that each user matches The receiving antenna number for the equivalent set.
CN201510202422.1A 2015-04-23 2015-04-23 Multiuser MIMO user choosing method based on conditional number Expired - Fee Related CN104868943B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201510202422.1A CN104868943B (en) 2015-04-23 2015-04-23 Multiuser MIMO user choosing method based on conditional number

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201510202422.1A CN104868943B (en) 2015-04-23 2015-04-23 Multiuser MIMO user choosing method based on conditional number

Publications (2)

Publication Number Publication Date
CN104868943A CN104868943A (en) 2015-08-26
CN104868943B true CN104868943B (en) 2019-02-05

Family

ID=53914497

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201510202422.1A Expired - Fee Related CN104868943B (en) 2015-04-23 2015-04-23 Multiuser MIMO user choosing method based on conditional number

Country Status (1)

Country Link
CN (1) CN104868943B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107864001B (en) * 2017-10-24 2020-10-23 深圳大学 Low-complexity antenna selection method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101150877A (en) * 2007-05-09 2008-03-26 中国科学技术大学 Improved multi-user selection method for block diagonally multi-in and multi-out system based on model
CN102130709A (en) * 2011-04-20 2011-07-20 中国科学技术大学 Multiple-input multiple-output (MIMO) multicasting beamforming method
CN102970116A (en) * 2012-12-10 2013-03-13 哈尔滨工业大学 Method for selecting user with maximum product of effective channel gains in downlink multi-user multiple-input multiple-output (MIMO)
CN104113399A (en) * 2014-07-15 2014-10-22 同济大学 Multi-user user selection method based on matrix condition number in multiple input multiple output (MIMO) system
CN104467930A (en) * 2014-12-09 2015-03-25 山东大学 Multi-user MIMO system user selection method based on space angle

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101150877A (en) * 2007-05-09 2008-03-26 中国科学技术大学 Improved multi-user selection method for block diagonally multi-in and multi-out system based on model
CN102130709A (en) * 2011-04-20 2011-07-20 中国科学技术大学 Multiple-input multiple-output (MIMO) multicasting beamforming method
CN102970116A (en) * 2012-12-10 2013-03-13 哈尔滨工业大学 Method for selecting user with maximum product of effective channel gains in downlink multi-user multiple-input multiple-output (MIMO)
CN104113399A (en) * 2014-07-15 2014-10-22 同济大学 Multi-user user selection method based on matrix condition number in multiple input multiple output (MIMO) system
CN104467930A (en) * 2014-12-09 2015-03-25 山东大学 Multi-user MIMO system user selection method based on space angle

Also Published As

Publication number Publication date
CN104868943A (en) 2015-08-26

Similar Documents

Publication Publication Date Title
CN109005551B (en) Multi-user NOMA downlink power distribution method of non-ideal channel state information
EP2321912B1 (en) Beamforming systems and method
US9363815B2 (en) Method for SDMA transmission in multicarrier MU MIMO system and base station
CN102055563B (en) Adaptive joint linear precoding method applicable to multi-base station coordination
CN107086886B (en) Double-layer precoding design for large-scale MIMO system fusion zero forcing and Taylor series expansion
CN101123819A (en) Apparatus and method for low-complexity scheduling in multi-user MIMO system
EP3185434B1 (en) Method and device for beamforming
CN101834646B (en) User selection method, user selection device and base station
US9912458B2 (en) Pilot allocation method based on coherence time for large-scale MIMO system
CN101882952A (en) Space division multiple address transmission method of statistical characteristic mode
Okamoto An improved proportional fair scheduling in downlink non-orthogonal multiple access system
CN110881010A (en) Statistical CSI-assisted multi-user NOMA downlink transmission method
CN102882570A (en) Optimum transceiving combined processing method for communication among equipment in mobile communication network
CN111630788B (en) Apparatus and method for nonlinear precoding
KR20130112743A (en) Method of communicating between base station and terminal based on interference alignment in multicell multiuser mimo interference channel and method and apparatus of communication using interference alignment and block successive interference pre-cancellation for multi-user multiple-input multiple-output interference channel
CN104868943B (en) Multiuser MIMO user choosing method based on conditional number
CN104467930B (en) Multiuser MIMO user choosing method based on Space Angle
CN108064070B (en) User access method for large-scale MIMO multi-cell network
CN107579762B (en) Multi-cell cooperative precoding method based on quantification and channel information statistics
US20240137079A1 (en) User selection for mu-mimo
CN101378287B (en) Down method for multi-user multi-input multi-output system
EP3574588A1 (en) Methods and apparatuses for transmit weights
Yang et al. A low complexity joint user grouping and resource allocation algorithm in massive MIMO systems
WO2020073342A1 (en) Non-linear precoding procedure
Boviz et al. Cost-aware fronthaul rate allocation to maximize benefit of multi-user reception in C-RAN

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
EXSB Decision made by sipo to initiate substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20190205

Termination date: 20190423