CN103117787A - Self-adaptive bit distributing method and self-adaptive bit distributing device in cooperative multi-aerial system - Google Patents

Self-adaptive bit distributing method and self-adaptive bit distributing device in cooperative multi-aerial system Download PDF

Info

Publication number
CN103117787A
CN103117787A CN2013100343204A CN201310034320A CN103117787A CN 103117787 A CN103117787 A CN 103117787A CN 2013100343204 A CN2013100343204 A CN 2013100343204A CN 201310034320 A CN201310034320 A CN 201310034320A CN 103117787 A CN103117787 A CN 103117787A
Authority
CN
China
Prior art keywords
channel
information
interference
channel information
feedback bits
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.)
Granted
Application number
CN2013100343204A
Other languages
Chinese (zh)
Other versions
CN103117787B (en
Inventor
康桂霞
桂鑫
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.)
Beijing University of Posts and Telecommunications
Original Assignee
Beijing University of Posts and Telecommunications
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 Beijing University of Posts and Telecommunications filed Critical Beijing University of Posts and Telecommunications
Priority to CN201310034320.4A priority Critical patent/CN103117787B/en
Publication of CN103117787A publication Critical patent/CN103117787A/en
Application granted granted Critical
Publication of CN103117787B publication Critical patent/CN103117787B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Mobile Radio Communication Systems (AREA)

Abstract

本发明提供了一种协同多天线系统中的自适应比特分配方法及装置,所述方法包括根据信道估计提取数据信号和干扰信号的接收功率以及各个信道的时延信息;根据信号接收功率和各个信道的时延信息分别计算在总反馈比特数固定的前提下为数据信道和各个干扰信道分配的最优反馈比特数,并将信道信息非理想状态造成的速率损失进行最小化处理;根据最优反馈比特数确定码本的大小,并利用理想信道信息根据最小弦距离准则从码本中选取相应的码字量化后的信道状态信息并发送;接收并根据所述量化的干扰信道信息生成迫零预编码矩阵。本发明通过基站利用获取的非理想信道信息进行迫零预编码操作,抑制本小区内的多用户干扰和对邻小区的小区间干扰。

Figure 201310034320

The present invention provides an adaptive bit allocation method and device in a cooperative multi-antenna system, the method includes extracting the received power of data signals and interference signals and the time delay information of each channel according to channel estimation; according to the signal received power and each The delay information of the channel calculates the optimal number of feedback bits allocated for the data channel and each interference channel under the premise that the total number of feedback bits is fixed, and minimizes the rate loss caused by the non-ideal state of the channel information; according to the optimal The number of feedback bits determines the size of the codebook, and uses the ideal channel information to select the corresponding codeword quantized channel state information from the codebook according to the minimum chord distance criterion and send it; receive and generate zero-forcing based on the quantized interference channel information precoding matrix. In the present invention, the base station uses the obtained non-ideal channel information to perform zero-forcing precoding operation, thereby suppressing multi-user interference in the local cell and inter-cell interference to neighboring cells.

Figure 201310034320

Description

Self-adaptive bit allocation method and device in a kind of collaborative multiaerial system
Technical field
The present invention relates to self-adaptive bit allocation method and device in a kind of collaborative multiaerial system, belong to wireless communication technology field.
Background technology
In wireless communication system, presence of intercell interference is the key factor that causes the Cell Edge User communication quality to reduce.For the user of center of housing estate, itself is closer from the distance of base station, and the interference signal of outer residential quarter is distant, and its Signal to Interference plus Noise Ratio is relatively large.User for cell edge, the user who takies same bandwidth resources due to neighbor cell is larger to its interference ratio, itself is far away apart from the base station in addition, its Signal to Interference plus Noise Ratio is relatively just less, although cause the throughput of residential quarter integral body higher, but the QoS of customer of cell edge is relatively poor, and throughput is lower.Therefore, in wireless communication system, it is extremely important that presence of intercell interference suppresses technology.
The method of traditional minimizing presence of intercell interference is the channeling technology.When cell cluster is more greatly frequency duplex factor as one when larger, presence of intercell interference can be reduced effectively, but spectrum efficiency also can correspondingly reduce simultaneously.Current, OFDM (Orthogonal Frequency Division Multiplexing, OFDM) has become an important technology of Next-Generation Wireless Communication Systems.In ofdm system, in order to improve power system capacity, frequency duplex factor as one should be close to 1, and this moment, spectrum efficiency was very high, but presence of intercell interference is but very serious.Therefore the problem that solves presence of intercell interference is most important for the raising of wireless communication system overall performance.
In the multi-cell coordination communication system based on frequency division multiplexing, the user can estimate complete interference channel information by channel estimation technique, and this information exchange is crossed based on feedback link feeds back to this cell base station.This cell base station passes to interference channel information by X2 interface the base station of this community user being caused interference.The base station of interfered cell utilizes the information of the interference channel that obtains to carry out the ZF pre-encode operation can eliminate interference to interfered cell fully.Yet in the Limited Feedback system based on code book, user feedback is to CSI (the Channel Statement Information of base station, channel condition information) be after quantizing, and there is channel delay to exist, not desirable CSI, therefore the ZF precoding still can't be eliminated interference fully, causes the existence of residual interference, and residual interference can cause the decline of user's transmission rate.
Summary of the invention
The embodiment of the present invention provides self-adaptive bit allocation method and the device in a kind of collaborative multiaerial system, obtains maximum transmission rate by utilizing fixing feedback overhead, to solve the problem of presence of intercell interference.For this reason, the present invention proposes following technical scheme:
Self-adaptive bit allocation method in a kind of collaborative multiaerial system comprises the following steps:
Extract the received power of this cell data channel information, adjacent cell interference channel information, data-signal and interference signal and the Delay of each channel according to channel estimating;
Calculate respectively according to the Delay of described signal received power and each channel the Optimal Feedback bit number that distributes for data channel and each interference channel under the prerequisite that total number of bits of feedback is fixed, and the rate loss that the channel information nonideality causes is carried out minimization, to obtain ideal communication channel information;
Determine the size of code book according to described Optimal Feedback bit number, and utilize described ideal communication channel information to choose channel condition information after corresponding code word quantizes according to the minimum chordal distance criterion from described code book, and described channel condition information is fed back to serving BS by the based on feedback link that time delay is arranged;
Receive the channel condition information of described quantification by the X2 interface that time delay is arranged, and generate the ZF pre-coding matrix according to the interference channel information of described quantification.
Adaptive bit distributor in a kind of collaborative multiaerial system comprises:
Receiving element is used for extracting the received power of this cell data channel information, adjacent cell interference channel information, data-signal and interference signal and the Delay of each channel according to channel estimating;
The feedback computing unit, calculate respectively the Optimal Feedback bit number that distributes for data channel and each interference channel under the prerequisite that total number of bits of feedback is fixed for the Delay according to described signal received power and each channel, and the rate loss that the channel information nonideality causes is carried out minimization, to obtain ideal communication channel information;
Quantize computing unit, be used for determining according to described Optimal Feedback bit number the size of code book, and utilize described ideal communication channel information to choose channel condition information after corresponding code word quantizes according to the minimum chordal distance criterion from described code book, and the index information that described channel condition information is corresponding feeds back to serving BS by the based on feedback link that time delay is arranged;
The base station precoding unit is used for receiving by the X2 interface that time delay is arranged the channel condition information of described quantification, and generates the ZF pre-coding matrix according to the interference channel information of described quantification.
The present invention utilizes the non-ideal communication channel information of obtaining to carry out the ZF pre-encode operation by the base station, thus suppress in this residential quarter multi-user interference and to the presence of intercell interference of adjacent cell.
Description of drawings
Accompanying drawing is used to provide a further understanding of the present invention, and consists of the part of specification, is used for together with embodiments of the present invention explaining the present invention, is not construed as limiting the invention.In the accompanying drawings:
Fig. 1 is the schematic flow sheet of the self-adaptive bit allocation method in collaborative multiaerial system provided by the invention;
Fig. 2 is the system block diagram of collaborative MIMO in the embodiment of the present invention;
Fig. 3 is the structural representation of the adaptive bit distributor in collaborative multiaerial system provided by the invention.
Embodiment
Below in conjunction with accompanying drawing, the preferred embodiments of the present invention are described, should be appreciated that preferred embodiment described herein only is used for description and interpretation the present invention, is not intended to limit the present invention.
As shown in Figure 1, the embodiment of the present invention provides the self-adaptive bit allocation method in a kind of collaborative multiaerial system, comprises the following steps:
Step 1 is extracted the received power of this cell data channel information, adjacent cell interference channel information, data-signal and interference signal and the Delay of each channel according to channel estimating;
Step 2, calculate respectively according to the Delay of described signal received power and each channel the Optimal Feedback bit number that distributes for data channel and each interference channel under the prerequisite that total number of bits of feedback is fixed, and the rate loss that the channel information nonideality causes is carried out minimization, to obtain ideal communication channel information;
Step 3, determine the size of code book according to described Optimal Feedback bit number, and utilize described ideal communication channel information to choose channel condition information after corresponding code word quantizes according to the minimum chordal distance criterion from described code book, and described channel condition information is fed back to serving BS by the based on feedback link that time delay is arranged;
Step 4 receives the channel condition information of described quantification, and generates the ZF pre-coding matrix according to the interference channel information of described quantification by the X2 interface that time delay is arranged.
In this embodiment, suppose that in the multi-cell coordination multi-input multi-output system M adjacent cell arranged around a reference cell, the base station in reference cell arranges K user to carry out simultaneously transfer of data.In system, each base station and each user configure respectively n TAnd n RWith antenna.When the multiplexing factor of system frequency was 1, each user can be subject to two kinds of interference: 1. from the inter-user interference of this residential quarter, and 2 presence of intercell interference from adjacent cell.In reference cell, k user receives, and (1≤m≤M) signal power of individual interference base station is respectively P from serving BS and m kWith Wherein
Figure BDA00002790498800032
Be power coefficient, namely the power of this cell data signal is better than the power of the interference signal of interfered cell. Value depend on and channel large scale decline comprise path loss and shadow fading.K user of reference cell is at the reception signal of time point n y k [ n ] ∈ G n R × 1 Can be written as:
y k [ n ] = H k [ n ] T k [ n ] x k [ n ] + H k [ n ] Σ j = 1 , j ≠ k K T j [ n ] x j [ n ] + Σ m = 1 M G k , m [ n ] T m [ n ] x m [ n ] + z k [ n ] - - - ( 1 )
Wherein
Figure BDA00002790498800041
With
Figure BDA00002790498800042
Be respectively reference cell and m interfered cell to the channel matrix of user k.
Figure BDA00002790498800043
Be the transmitting data vector, satisfy maximum transmit power limit:
Figure BDA00002790498800044
Figure BDA00002790498800045
Be piece diagonal angle precoding unitary matrice.z k[n] expression is obeyed and is distributed as CN (0, σ 2) multiple Gaussian noise vector.
In this embodiment, H k[n] and G K, m[n] has respectively the code book W that quantizes (RVQ) based on random vector kAnd W k,mQuantize.Generate in advance under each user code book used is all online and transmitting-receiving two-end all obtains the full content of code book in advance.Code book W kAnd W k,mSize be respectively
Figure BDA00002790498800046
With
Figure BDA00002790498800047
Namely
Figure BDA00002790498800048
Figure BDA00002790498800049
Wherein in code book, each element is random half unitary matrice that generates.Suppose that the total feedback bandwidth of each user is B totBit, wherein B kAnd B k,mBit quantizes respectively H k[n] and G K, m[n].The user goes out corresponding code word as the channel matrix after quantizing from codebook selecting
Figure BDA000027904988000410
With
Figure BDA000027904988000411
System of selection is according to the minimum chordal distance criterion:
H ^ k [ n ] = arg min d 2 W k ∈ W k ( H k [ n ] , W k ) (2)
G ^ k , m [ n ] = arg min d 2 W k , m ∈ W k , m ( G k , m [ n ] , W k , m )
The channel delay that causes due to feedback and the information interaction of X2 interface also can cause systemic loss of energy.Become the piece fading channel model when considering in this concrete enforcement, namely channel in a mark space fix and adjacent-symbol between channel response be correlated with.Channel relevancy can be expressed as:
H k[n]=η kH k[n-D k]+E k[n] (3)
G k,m[n]=η k,mG k,m[n-D k,m]+E k,m[n]
E wherein k[n] and E K, m[n] is the channel errors matrix, and and H k[n-D k] and G K, m[n-D k,m] relatively independent.D kAnd D k,mBe respectively the sampled point number of channel delay.E k[n] and E K, mElement in [n] is obeyed and is distributed
Figure BDA000027904988000414
With
Figure BDA000027904988000415
And satisfy respectively
Figure BDA000027904988000416
Figure BDA000027904988000417
Coefficient correlation η kAnd η k,mDetermined by carat card autocorrelation model:
η k=J 0(2πf dD kT s) (4)
η k,m=J 0(2πf dD k,mT s)
Wherein, J 0() is 0 rank Bessel function of the first kind, f dBe Doppler frequency shift, T sBe mark space.
When transmitting terminal can obtain desirable channel condition information without time delay, adopt based on the collaborative piece diagonal angle method for precoding of ZF and can eliminate presence of intercell interference and inter-user interference fully, its pre-coding matrix satisfies following restriction:
H j[n]T k[n]=0,forj=1,2…Kand j≠k (5)
G k,m[n]T k[n]=0,for1≤m≤M
Wherein in (5) formula, first equation represents that the ZF of disturbing in the residential quarter limits, and second equation represents the ZF restriction of presence of intercell interference.Thereby in the residential quarter, k user's pre-coding matrix should be included in
Figure BDA00002790498800051
Kernel in.
Figure BDA00002790498800052
May be defined as
Figure BDA00002790498800053
Wherein
Figure BDA00002790498800054
With Be respectively the polymer matrix of multi-user interference channel and presence of intercell interference channel:
H ~ k [ n ] = ( H 1 T [ n ] · · · H k - 1 T [ n ] H k + 1 T [ n ] · · · H K T [ n ] ) T (6)
G ~ k [ n ] = ( G k , 1 T [ n ] · · · G k , m T [ n ] · · · G k , M T [ n ] ) T
Right
Figure BDA00002790498800058
Carrying out the standard singular value decomposition can get
Π ~ k [ n ] = U ~ k [ n ] Σ ~ k [ n ] ( V ~ k ( 1 ) [ n ] V ~ k ( 0 ) [ n ] ) H - - - ( 7 )
Figure BDA000027904988000510
Formed
Figure BDA000027904988000511
One group of orthonormal basis of right null space.Order
Figure BDA000027904988000512
Can satisfy the restriction in (5) formula.In this embodiment, concentrate on n T〉=(K-1) n R+ Mn RSituation to satisfy the restriction of antenna dimension.Can adopt dynamic clustering cooperation and multi-subscriber dispatching algorithm to reduce the value of K and M.When transmitting terminal had the ideal communication channel state information, piece diagonal angle method for precoding can be deleted multi-user interference and presence of intercell interference fully, and user's average transmission rate expression formula is:
C k = E [ log 2 det ( I n R + P k σ 2 H k [ n ] T k [ n ] T k H [ n ] H k H [ n ] ) ] - - - ( 8 )
Consideration is in real system, and transmitting terminal can't obtain desirable channel condition information without time delay, the base station n constantly only can obtain quantize and the time data channel information delayed
Figure BDA000027904988000514
And interference channel information
Figure BDA000027904988000515
Employing piece diagonal angle pre-coding matrix
Figure BDA000027904988000516
The phase mutual interference can't be eliminated fully, only following restriction can be satisfied:
H ^ j [ n - D k ] T ^ k [ n ] = 0 , forj = 1,2 · · · Kandj ≠ k · (9)
Figure BDA000027904988000518
Under non-ideal communication channel, user's average transmission rate expression formula is:
G ^ k = E [ lo g 2 det ( I n R + P k σ 2 H k [ n ] T ^ k [ n ] H ^ k H [ n ] R k - 1 [ n ] ) ] - - - ( 10 )
R wherein k[n] is the covariance matrix of k user's interference plus noise, is expressed as:
R k [ n ] = P k H k [ n ] Σ j = 1 , j ≠ k K T ^ j [ n ] T ^ j H [ n ] (11)
+ Σ m = 1 M ∂ k , m P k G k , m [ n ] T ^ m [ n ] T ^ m H [ n ] G k , m H [ n ] + σ 2 I n R
Because non-ideal communication channel information exists, the interference in (10) formula can't be removed fully, namely
Figure BDA00002790498800064
With
Figure BDA00002790498800065
Thereby residual interference can worsen systematic function.
At first derive when existing based on Limited Feedback and channel delay the closed expression of the difference of user's transmission rate under user's transmission rate and ideal communication channel situation in this embodiment, and proposed a kind of adaptive bit allocation algorithm based on this closed expression.Wherein, the closed expression of the undesirable rate loss that causes of channel condition information is derived as follows:
ΔC k = C k - C ^ k
= E [ log 2 det ( I n R + P k σ 2 H k [ n ] T k [ n ] T k H [ n ] H k H [ n ] ) ]
- E [ log 2 det ( R k [ n ] + P k σ 2 H k [ n ] T ^ k [ n ] T ^ k H [ n ] ) ] + E [ log 2 det ( R k [ n ] ) ]
≤ ( a ) E [ log 2 det ( R k [ n ] ) ] (12)
≤ ( b ) log 2 det [ E ( R k [ n ] ) ]
Figure BDA000027904988000611
= ( c ) log 2 det [ P k Φ k η k 2 ( K - 1 ) n T - n R n T I n R + ( K - 1 ) ϵ k 2 n R I n R + Σ m = 1 M ( ∂ k , m P k Φ k , m η k , m 2 n T - n R n T I n R + ϵ k , m 2 n R I n R ) + σ 2 I n R ]
Wherein ignored R in (a) formula kThe part positive semidefinite item of [n].T k[n] and
Figure BDA000027904988000613
Be isotropic distribution, and and H k[n] is separate, therefore H k [ n ] T k [ n ] T k H [ n ] H k H [ n ] With H k [ n ] H ^ k [ n ] T ^ k H [ n ] H k H [ n ] Expectation equate.(b) formula is inequality gloomy according to letter.The derivation of equation (c) is as follows:
Have for the S1 item:
E ( H k [ n ] Σ j = 1 , j ≠ k K T j [ n ] T j H [ n ] H k H [ n ] ) =
= ( d ) E ( η k 2 H k [ n - D k ] Σ j = 1 , j ≠ k K T j [ n ] T j H [ n ] H k H [ n - D k ] ) + E ( E k [ n ] Σ j = 1 , j ≠ k K T j [ n ] T j H [ n ] E k H [ n ] ) (13)
= ( e ) E ( η k 2 H ~ k [ n - D k ] Σ j = 1 , j ≠ k K T j [ n ] T j H [ n ] H ~ k H [ n - D k ] Λ K ) + ( K - 1 ) ϵ k 2 n R I n R
= ( f ) Φ k η k 2 ( K - 1 ) n T - n R n T I n R + ( K - 1 ) ϵ k 2 n R I n R
Wherein (d) formula is according to equation (3) and E k[n] and H k[nD k] independent distribution.(e) formula is according to H k[n-D k] the Eigenvalues Decomposition expression formula: H k H [ n - D k ] H k [ n - D k ] = H ~ k H [ n - D k ] Λ k H ~ k [ n - D k ] , Wherein H ~ k [ n - D k ] Formed H k[nD k] the column vector subspace of opening in one group of orthonormal basis.Λ kBe diagonal matrix, its diagonal entry is
Figure BDA00002790498800077
N RIndividual non-zero, the characteristic value of descending.(e) formula is according to E k[n] is multiple Gauss's matrix and T j[n] is unitary matrice, thereby E k[n] T j[n] also obeys for each element
Figure BDA00002790498800078
The Gauss's matrix that distributes.Matrix
Figure BDA00002790498800079
Can decompose as follows:
H ~ k [ n - D k ] = A k B k H ^ k [ n - D k ] + S k C k - - - ( 14 )
Wherein
Figure BDA000027904988000711
Be the orthonormal basis of one group of isotropic distribution, open into
Figure BDA000027904988000712
Left kernel in n RDimensional plane.C kN R* n RUpper triangular matrix, its diagonal entry are on the occasion of also satisfying: tr ( C k C k H ) = d 2 ( H ~ k [ n ] , H ^ k [ n ] ) . And, S kAnd C kSeparate.According to (14) Shi Kede:
E ( η k 2 H ~ k [ n - D k ] Σ j = 1 , j ≠ k K T j [ n ] T j H [ n ] H ~ k H [ n - D k ] Λ K )
= η k 2 ( K - 1 ) E [ C k ( S k T j [ n ] T j H [ n ] S k H ) C k H Λ K ] - - - ( 15 )
= η k 2 ( K - 1 ) n T n T - n R E ( C k C k H Λ K )
(15) in formula last equation according to S kAnd T j[n] isotropic distribution exists
Figure BDA000027904988000717
Left kernel in and both are separate, thereby For matrix immediately variable to obey parameter be n RAnd n T-2n RBeta distribute, namely E [ S k T j [ n ] T j H [ n ] S k H ] = n R n T - n R . Character according to (14) formula matrix decomposition has E ( Λ k ) = n T I n R ,
Figure BDA000027904988000721
Φ wherein kFor quantization error can be approximately equal to:
Φ k ≈ Γ ( 1 T ) T ( C n T n R ) - 1 T 2 - B k T - - - ( 16 )
T=n wherein R(n T-n R), C n T n R = 1 T ! Π i = 1 n R ( n T - i ) ! ( n R - i ) ! , Thereby obtain (f) formula.
Derivation and the S1 of S2 are similar, as follows:
E ( G k , m [ n ] Σ m = 1 M T ^ m [ n ] T ^ m H [ n ] G k , m H [ n ] ) =
E ( Σ m = 1 M η k , m 2 G k [ n - D k , m ] T ^ m [ n ] T ^ m H [ n ] G k , m H [ n - D k , m ] + Σ m = 1 M E k , m [ n ] T ^ m [ n ] T ^ m H [ n ] E k , m H [ n ] ) (17)
= E ( Σ m = 1 M η k , m 2 G ~ k [ n - D k , m ] T ^ m [ n ] T ^ m H [ n ] G ~ k , m H [ n - D k , m ] Λ k , m ) + M ϵ k , m 2 n R I n R
= Σ m = 1 M Φ k , m η k , m 2 n T - n R n T I n R + ϵ k , m 2 n R I n R
Wherein
Figure BDA00002790498800087
Form G k[n-D k,m] column vector open into one group of orthonormal basis in space, Λ K, mBe diagonal matrix, its diagonal entry is N RIndividual non-zero, the characteristic value of descending.Φ K, mBe quantization error:
Φ k , m ≈ Γ ( 1 T ) T ( C n T n R ) - 1 T 2 - B k , m T - - - ( 18 )
The closed expression that finally obtains the rate loss that Limited Feedback and channel delay cause is:
ΔC k ≤ n R lo g 2 ( P k Φ k η k 2 ( K - 1 ) n T - n R n T + ( K - 1 ) ϵ k 2 n R + Σ m = 1 M ∂ k , m P k Φ k , m η k , m 2 n T - n R n T + ϵ k , m 2 n R + σ 2 ) - - - ( 19 )
By (19) formula as can be known, rate loss causes mainly due to two factors: residual multi-user interference and presence of intercell interference.A key issue is the total number of bits of feedback B as each user totIn the time of fixedly, in order to minimize rate loss, should be how many number of bits of feedback B of data channel assignment kAnd should be interference channel and distribute how many bit number B K, mNext this embodiment will propose a kind of novel optimal bit allocative decision, to minimize the rate loss of (19) formula.
According to (19) formula, notice that logarithmic function is monotonic increasing function, ignore constant term, can get target function as follows:
min P ‾ k 2 - B k T + Σ m = 1 M P ‾ k , m 2 - B k , m T (20)
s · t · B k + Σ m = 1 M B k , m = B tot
Wherein, P ‾ k P k η k 2 n T Γ ( 1 T ) ( C n T n R ) - 1 T ( K - 1 ) T ( n T - n R ) , P ‾ k , m = ∂ k , m P k η k , m 2 n T Γ ( 1 T ) ( C n T n R ) - 1 T T ( n T - n R ) .
(20) formula is convex function, available protruding Optimization Method.Lagrangian can be written as:
L ( B k , B k , m , λ ) = P ‾ k 2 - B k T + Σ m = 1 M P ‾ k , m 2 - B k , m T + λ ( B k + Σ m = 1 M B k , m - B tot ) - - - ( 21 )
According to (21) formula, can get the optimum KKT condition of single order as follows:
∂ L ( B k , B k , m , λ ) ∂ B k = - ln ( 2 ) P ‾ k T 2 - B k T + λ = 0
∂ L ( B k , B k , m , λ ) ∂ B k , m = - ln ( 2 ) P ‾ k , m T 2 - B k , m T + λ = 0 - - - ( 22 )
∂ L ( B k , B k , m , λ ) ∂ λ = B k + Σ m = 1 M B k , m - B tot = 0
Find the solution the equation in (22) formula, can get optimal solution as follows:
B k opt = [ B tot M + 1 + Tlo g 2 ( P ‾ k ( P ‾ k Π m = 1 M P ‾ k , m ) 1 M + 1 ) ] + , B k , m opt [ B tot M + 1 + T log 2 ( P ‾ k , m ( P ‾ k Π m = 1 M P ‾ k , m ) 1 M + 1 ) ] + - - - ( 23 )
Wherein
Figure BDA00002790498800096
By (23) formula as can be known Along with
Figure BDA00002790498800098
Increase and increase.Also namely or data channel time delay strong when the power of data-signal hour, system can distribute more number of bits of feedback to come the quantized data channel.On the contrary, when interference channel stronger, time delay hour, more number of bits of feedback can be distributed to the quantification interference channel.In other words, this embodiment is put forward the algorithm self adaptation must be stronger for power, the feedback bits that the channel allocation that time delay is less is more; For power a little less than, the feedback bits that the channel allocation that time delay is larger is less is to minimize rate loss.
Self-adaptive bit allocation method in the collaborative multiaerial system that this embodiment is provided below by specific embodiment is elaborated.In multiaerial system block diagram shown in Figure 2, each user not only receives the data channel of this residential quarter, can be subject to the interference of adjacent cell signal simultaneously, the user utilizes channel estimating to obtain the channel condition information of data channel and interference channel, and will feed back to serving BS after these information quantizations.Serving BS passes to the interfered cell base station by X2 interface with interference channel information again.
The base station is the broadcast channel periodically.The user utilizes channel estimating to estimate the channel information of this cell data channel and adjacent cell interference channel and the relevant information of signal power and time delay.The user utilizes the information of signal power and time delay to calculate respectively the Optimal Feedback bit number of data channel and the distribution of each interference channel according to (22) formula.Determine the Optimal Feedback bit number, also namely determined the size of code book, as W kAnd W k,mSize be respectively
Figure BDA00002790498800099
With
Figure BDA000027904988000910
The user selects corresponding code word as the channel matrix after quantizing from code book respectively according to the minimum chordal distance criterion
Figure BDA000027904988000911
With
Figure BDA000027904988000912
And the code book indication information is fed back to serving BS by the feedback channel that time delay is arranged.The base station by X2 interface with interference channel information Pass to corresponding adjacent cell base station.The base station utilize the non-ideal communication channel information obtain carry out the ZF pre-encode operation with suppress in this residential quarter multi-user interference and to the presence of intercell interference of adjacent cell.
For realizing said method, the embodiment of the present invention has also proposed the adaptive bit distributor in a kind of collaborative multiaerial system, as shown in Figure 3, comprising:
Receiving element 31 is used for extracting the received power of this cell data channel information, adjacent cell interference channel information, data-signal and interference signal and the Delay of each channel according to channel estimating;
Feedback computing unit 32, calculate respectively the Optimal Feedback bit number that distributes for data channel and each interference channel under the prerequisite that total number of bits of feedback is fixed for the Delay according to described signal received power and each channel, and the rate loss that the channel information nonideality causes is carried out minimization, to obtain ideal communication channel information;
Quantize computing unit 33, be used for determining according to described Optimal Feedback bit number the size of code book, and utilize described ideal communication channel information to choose channel condition information after corresponding code word quantizes according to the minimum chordal distance criterion from described code book, and the index information that described channel condition information is corresponding feeds back to serving BS by the based on feedback link that time delay is arranged;
Base station precoding unit 34 is used for receiving by the X2 interface that time delay is arranged the channel condition information of described quantification, and generates the ZF pre-coding matrix according to the interference channel information of described quantification.
Preferably, comprise at feedback computing unit 32;
The minimization subelement is used to the more feedback bits of channel allocation that signal power is strong, time delay is less; Be the less feedback bits of channel allocation that signal power is weak, time delay is larger.
Preferably, comprise in base station precoding unit 4;
Disturb to suppress subelement, be used for utilizing singular value decomposition to obtain the kernel matrix of interference channel, and utilize this kernel matrix as pre-coding matrix to suppress this two kinds of interference.
The embodiment of the processing capacity of each unit that comprises in the adaptive bit distributor in above-mentioned collaborative multiaerial system is described in method execution mode before, no longer is repeated in this description at this.
Adopt the scheme of the present embodiment, utilize the non-ideal communication channel information of obtaining to carry out the ZF pre-encode operation by the base station, thus suppress in this residential quarter multi-user interference and to the presence of intercell interference of adjacent cell.
The above; only for the better embodiment of the present invention, but protection scope of the present invention is not limited to this, anyly is familiar with those skilled in the art in the technical scope that the present invention discloses; the variation that can expect easily or replacement are within all should being encompassed in protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection range of claim.

Claims (6)

1.一种协同多天线系统中的自适应比特分配方法,其特征在于,包括以下步骤:1. an adaptive bit allocation method in a cooperative multi-antenna system, is characterized in that, comprises the following steps: 根据信道估计提取本小区数据信道信息、邻小区干扰信道信息、数据信号和干扰信号的接收功率以及各个信道的时延信息;Extract the data channel information of the cell, the interference channel information of the adjacent cell, the received power of the data signal and the interference signal, and the delay information of each channel according to the channel estimation; 根据所述信号接收功率和各个信道的时延信息分别计算在总反馈比特数固定的前提下为数据信道和各个干扰信道分配的最优反馈比特数,并将信道信息非理想状态造成的速率损失进行最小化处理,以获得理想信道信息;According to the received signal power and the delay information of each channel, calculate the optimal number of feedback bits allocated for the data channel and each interference channel under the premise that the total number of feedback bits is fixed, and calculate the rate loss caused by the non-ideal state of channel information Minimize to obtain ideal channel information; 根据所述最优反馈比特数确定码本的大小,并利用所述理想信道信息根据最小弦距离准则从所述码本中选取相应的码字量化后的信道状态信息,并将所述信道状态信息通过有时延的反馈链路反馈给服务基站;Determine the size of the codebook according to the optimal number of feedback bits, and use the ideal channel information to select the corresponding codeword quantized channel state information from the codebook according to the minimum chordal distance criterion, and store the channel state The information is fed back to the serving base station through a time-delayed feedback link; 通过有时延的X2接口接收所述量化的信道状态信息,并根据所述量化的干扰信道信息生成迫零预编码矩阵。The quantized channel state information is received through a time-delayed X2 interface, and a zero-forcing precoding matrix is generated according to the quantized interference channel information. 2.根据权利要求1所述的方法,其特征在于,所述将信道信息非理想状态造成的速率损失进行最小化处理包括:2. The method according to claim 1, wherein the minimizing the rate loss caused by the non-ideal state of channel information comprises: 为信号功率较强、时延较小的信道分配较多的反馈比特;为信号功率较弱、时延较大的信道分配较少的反馈比特。Allocate more feedback bits to channels with stronger signal power and smaller time delay; allocate less feedback bits to channels with weaker signal power and longer time delay. 3.根据权利要求1所述的方法,其特征在于,所述根据所述量化的干扰信道信息生成迫零预编码矩阵包括:3. The method according to claim 1, wherein said generating a zero-forcing precoding matrix according to said quantized interference channel information comprises: 利用奇异值分解获取干扰信道的零空间矩阵,并利用该零空间矩阵作为预编码矩阵以抑制这两种干扰。The null space matrix of the interfering channel is obtained by singular value decomposition, and the null space matrix is used as a precoding matrix to suppress the two kinds of interference. 4.一种协同多天线系统中的自适应比特分配装置,其特征在于,包括:4. An adaptive bit allocation device in a cooperative multi-antenna system, characterized in that it comprises: 接收单元,用于根据信道估计提取本小区数据信道信息、邻小区干扰信道信息、数据信号和干扰信号的接收功率以及各个信道的时延信息;The receiving unit is used to extract the data channel information of the current cell, the interference channel information of the adjacent cell, the received power of the data signal and the interference signal, and the delay information of each channel according to the channel estimation; 反馈计算单元,用于根据所述信号接收功率和各个信道的时延信息分别计算在总反馈比特数固定的前提下为数据信道和各个干扰信道分配的最优反馈比特数,并将信道信息非理想状态造成的速率损失进行最小化处理,以获得理想信道信息;The feedback calculation unit is used to calculate the optimal number of feedback bits allocated for the data channel and each interference channel under the premise that the total number of feedback bits is fixed according to the received signal power and the time delay information of each channel, and the channel information Minimize the rate loss caused by the ideal state to obtain ideal channel information; 量化计算单元,用于根据所述最优反馈比特数确定码本的大小,并利用所述理想信道信息根据最小弦距离准则从所述码本中选取相应的码字量化后的信道状态信息,并将所述信道状态信息对应的索引信息通过有时延的反馈链路反馈给服务基站;a quantization calculation unit, configured to determine the size of the codebook according to the optimal number of feedback bits, and use the ideal channel information to select the corresponding codeword quantized channel state information from the codebook according to the minimum chordal distance criterion, and feeding back index information corresponding to the channel state information to the serving base station through a time-delayed feedback link; 基站预编码单元,用于通过有时延的X2接口接收所述量化的信道状态信息,并根据所述量化的干扰信道信息生成迫零预编码矩阵。The base station precoding unit is configured to receive the quantized channel state information through a time-delayed X2 interface, and generate a zero-forcing precoding matrix according to the quantized interference channel information. 5.根据权利要求4所述的装置,其特征在于,在所述反馈计算单元中包括;5. The device according to claim 4, characterized in that, the feedback calculation unit includes; 最小化处理子单元,用于为信号功率较强、时延较小的信道分配较多的反馈比特;为信号功率较弱、时延较大的信道分配较少的反馈比特。The minimization processing subunit is configured to allocate more feedback bits to channels with strong signal power and small time delay; allocate less feedback bits to channels with weak signal power and large time delay. 6.根据权利要求4所述的装置,其特征在于,在所述基站预编码单元中包括;6. The device according to claim 4, wherein the base station precoding unit includes; 干扰抑制子单元,用于利用奇异值分解获取干扰信道的零空间矩阵,并利用该零空间矩阵作为预编码矩阵以抑制这两种干扰。The interference suppression subunit is used to obtain the null space matrix of the interference channel by using singular value decomposition, and use the null space matrix as a precoding matrix to suppress the two types of interference.
CN201310034320.4A 2013-01-29 2013-01-29 Self-adaptive bit allocation method and device in a kind of collaboration multiaerial system Expired - Fee Related CN103117787B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201310034320.4A CN103117787B (en) 2013-01-29 2013-01-29 Self-adaptive bit allocation method and device in a kind of collaboration multiaerial system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201310034320.4A CN103117787B (en) 2013-01-29 2013-01-29 Self-adaptive bit allocation method and device in a kind of collaboration multiaerial system

Publications (2)

Publication Number Publication Date
CN103117787A true CN103117787A (en) 2013-05-22
CN103117787B CN103117787B (en) 2017-07-28

Family

ID=48416070

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201310034320.4A Expired - Fee Related CN103117787B (en) 2013-01-29 2013-01-29 Self-adaptive bit allocation method and device in a kind of collaboration multiaerial system

Country Status (1)

Country Link
CN (1) CN103117787B (en)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104468056A (en) * 2014-11-06 2015-03-25 中国科学院计算技术研究所 Energy efficiency feedback method and device for CoMP technology in LTE-A downlink system
CN104539337A (en) * 2014-12-26 2015-04-22 东南大学 Limited feedback transmission method based on channel estimation in multi-antenna safety communication system
CN104579444A (en) * 2014-12-24 2015-04-29 无锡北邮感知技术产业研究院有限公司 Interference alignment method in heterogeneous cellular network
CN105933042A (en) * 2016-04-20 2016-09-07 重庆大学 Novel adaptive finite feedback method based on clustering in LTE system
CN106253958A (en) * 2016-09-19 2016-12-21 浙江大学 A kind of channel information feedback method based on the nonopiate multi-access systems of multiple antennas
CN108111203A (en) * 2017-11-17 2018-06-01 中兴通讯股份有限公司 The method and device that a kind of method, apparatus, the information of information feedback receive
CN109714722A (en) * 2018-12-03 2019-05-03 京信通信系统(中国)有限公司 Management method, device, electronic equipment and the storage medium of domestic aerial
CN111077504A (en) * 2020-01-16 2020-04-28 深圳大学 Mixed interference signal generation method, device, equipment and medium
WO2023116516A1 (en) * 2021-12-20 2023-06-29 华为技术有限公司 Method and apparatus for reporting channel information

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040151145A1 (en) * 2003-01-30 2004-08-05 Hammerschmidt Joachim S. Channel estimation for an OFDM transceiver
CN101039137A (en) * 2007-04-19 2007-09-19 上海交通大学 Method and system for reducing codebook search-based precoding feedback bits of MIMO-OFDM system
CN102130708A (en) * 2010-01-15 2011-07-20 华为技术有限公司 Feedback method and user equipment for multi-cell channel state information

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040151145A1 (en) * 2003-01-30 2004-08-05 Hammerschmidt Joachim S. Channel estimation for an OFDM transceiver
CN101039137A (en) * 2007-04-19 2007-09-19 上海交通大学 Method and system for reducing codebook search-based precoding feedback bits of MIMO-OFDM system
CN102130708A (en) * 2010-01-15 2011-07-20 华为技术有限公司 Feedback method and user equipment for multi-cell channel state information

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
GUI XIN AND KANG GUIXIA: "Rate maximizing with adaptive bit partition in cooperative distributed antenna system", 《IEEE》 *

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104468056A (en) * 2014-11-06 2015-03-25 中国科学院计算技术研究所 Energy efficiency feedback method and device for CoMP technology in LTE-A downlink system
CN104579444A (en) * 2014-12-24 2015-04-29 无锡北邮感知技术产业研究院有限公司 Interference alignment method in heterogeneous cellular network
CN104579444B (en) * 2014-12-24 2018-04-03 无锡北邮感知技术产业研究院有限公司 Interference alignment schemes in a kind of isomery cellular network
CN104539337B (en) * 2014-12-26 2017-09-29 东南大学 Limited Feedback transmission method based on channel estimation in multiple antennas safe communication system
CN104539337A (en) * 2014-12-26 2015-04-22 东南大学 Limited feedback transmission method based on channel estimation in multi-antenna safety communication system
CN105933042A (en) * 2016-04-20 2016-09-07 重庆大学 Novel adaptive finite feedback method based on clustering in LTE system
CN105933042B (en) * 2016-04-20 2018-12-18 重庆大学 Adaptive Limited Feedback new method based on sub-clustering in a kind of LTE system
CN106253958A (en) * 2016-09-19 2016-12-21 浙江大学 A kind of channel information feedback method based on the nonopiate multi-access systems of multiple antennas
CN106253958B (en) * 2016-09-19 2019-07-16 浙江大学 A Channel Information Feedback Method Based on Multi-antenna Non-Orthogonal Multiple Access System
CN108111203A (en) * 2017-11-17 2018-06-01 中兴通讯股份有限公司 The method and device that a kind of method, apparatus, the information of information feedback receive
WO2019096230A1 (en) * 2017-11-17 2019-05-23 中兴通讯股份有限公司 Information feedback method and device, method and device for receiving information
CN109714722A (en) * 2018-12-03 2019-05-03 京信通信系统(中国)有限公司 Management method, device, electronic equipment and the storage medium of domestic aerial
CN109714722B (en) * 2018-12-03 2020-11-10 京信通信系统(中国)有限公司 Management method and device of indoor antenna, electronic equipment and storage medium
CN111077504A (en) * 2020-01-16 2020-04-28 深圳大学 Mixed interference signal generation method, device, equipment and medium
WO2023116516A1 (en) * 2021-12-20 2023-06-29 华为技术有限公司 Method and apparatus for reporting channel information

Also Published As

Publication number Publication date
CN103117787B (en) 2017-07-28

Similar Documents

Publication Publication Date Title
US8644180B2 (en) MU-MIMO-OFDMA methods and systems for signaling multi-rank CQIs and precoders
CN103117787A (en) Self-adaptive bit distributing method and self-adaptive bit distributing device in cooperative multi-aerial system
US8848822B2 (en) Feedback method for interference alignment in wireless network
CN101369837B (en) Apparatus and method for beamforming using finite feedforward channel
US9680549B2 (en) User scheduling and beamformer design method, apparatus, and storage medium based on two-stage beamformer for massive MIMO downlink
CN101662321B (en) Method for sending secondary pre-code based on zero subspace technology in cognitive radio MIMO system
CN1855763B (en) Random beam forming method for multi-input multi-output system
CN106060950B (en) It is a kind of that data transmission method in the cellular downlink channel of alignment is interfered based on chance
CN103166688B (en) A kind of implementation method of precoding, device and mimo system
CN101453259A (en) Pre-encoded transmission method for MIMO system
CN105681009B (en) Pilot tone optimization distribution joint method for precoding for multi-user's multiple-input and multiple-output
CN104767556A (en) Beamforming coordination method and device based on partial interference alignment
CN101567765B (en) Distribution type space-time pre-coding transmission method based on channel angle domain information
CN102882570B (en) Optimum transceiving combined processing method for communication among equipment in mobile communication network
CN101340218A (en) Communication method and device in multiple input multiple output system
CN102811491B (en) Limited Feedback bit number combined distributing method in multipoint cooperative system
CN107425891B (en) Energy efficiency joint optimization method in MU-MIMO wireless energy/data transmission
CN102088789A (en) Channel information feedback adaptive transmission and bandwidth allocation method used in wireless communication
CN101834650A (en) A multi-user MIMO downlink transmission scheduling method
Hammarwall et al. Utilizing the spatial information provided by channel norm feedback in SDMA systems
CN106028461A (en) Relay Cooperative Distributed Multi-User Scheduling Method
CN102136891A (en) Improved channel state information (CSI) limited feedback method for multi-user multiple input multiple output (MU-MIMO) system
CN103607260B (en) System total interference leakage minimum pre-coding matrix group selection algorithm based on MIMO
CN105763238A (en) Multi-user MIMO system user selection method based on quantitative precoding
CN108242950A (en) A D2D-based CSI Feedback Method in FDD Massive MIMO Networks

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into 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

Granted publication date: 20170728

CF01 Termination of patent right due to non-payment of annual fee