CN102957516B - Adaptive data retransmission method and device - Google Patents

Abstract

The invention relates to the technical field of communication, in particular to adaptive data retransmission method and device. The method includes: a data receiver decodes received data and transmits a retransmission request to a base station in case of decoding errors; and after receiving the retransmission request, the base station selects an optimal retransmission coding matrix from a space-time coding matrix set according to optimal retransmission selection rules and respectively transmits the retransmitted data, newly transmitted data and an optimal preprocessing matrix number to relays, and the relays load the retransmitted data and the newly transmitted data transmitted by the base station into the optimal retransmission coding matrix in a distributed manner and forward the data to the data receiver. The method guarantees full diversity, high rate and linear decoding complexity of a retransmitted data stream and also guarantees real-time transmission of another data stream to be insusceptible to retransmission of the data stream, and resource utilization rate is high.

Description

A kind of adaptive retransmit method of data and device

Technical field

The application relates to wireless communication technology field, particularly relates to a kind of adaptive retransmit method and device of data.

Background technology

In broadband wireless communications; classified service is by different Q OS (Quality of Service; service quality) grade data flow by the technology such as superimposed coding, hierarchical modulation merge send; under the prerequisite of the multiple data flow of protection priority separately; realize transmitting, to save system resource simultaneously.But, different demands may be there is in the data flow that classification transmits in performance, time delay etc., such as, phone VOIP (Voiceove rInternet Protocol, the networking telephone) and data download two kinds of business when carrying out classification, VOIP has delay sensitive characteristic, does not support to retransmit; And data download more lays particular emphasis on transmission quality, support to retransmit with the accuracy ensureing Received signal strength.Therefore, a kind of partial retransmission method for classified service is needed to address this problem.

A kind of repeating method for classified service is there is in prior art; the general principle of this method is: the first stage; base station (eNB; evolved Node B) send signal to relaying (Relay); adopt the data stream merging transmission of different priorities based on the hierarchical modulation technology of qam constellation; high-priority traffic is mapped to high protection bit; the data stream of low priority to low protection bit, thus enables the data flow of different priorities transmit simultaneously.Second stage, each relaying Relay forwards with amplification forwarding (AF) form the base station eNB received to UE (USEREquipment, user terminal) simultaneously and signaled, and transmission form is wherein a line of selected space-time coding matrices.At receiver place, adopt single complex symbol ML decoding (Single Complex Symbol ML Decoding, SCSML) to solve the data of high and low priority two stream simultaneously.When having first-class making a mistake in two data flow of different priorities, base station eNB retransmits the data made a mistake.At this moment, keep original priority of data retransmission constant, and the new biography data of another one data flow carry out hierarchical modulation, realize merging transmission.At each relaying Relay place, carry out AF forwarding according to original encoder matrix form.After receiver receives retransmission frame data, first carry out single complex symbol ML decoding, obtain data retransmission and new biography data, data retransmission is carried out soft demodulation, obtain Soft Inform ation, and then Soft Inform ation when transmitting first with these data merges, and then carries out channel decoding.

In the process realizing the application, inventor finds that in prior art, at least there are the following problems: the technical scheme of prior art is when retransmitting generation, fixing encoder matrix is still adopted to data retransmission and new biography data, do not consider whether this encoder matrix form is still applicable to current instantaneous channel state, can not ensure the reliability retransmitted.

On the other hand, receiver adopts single complex symbol maximum-likelihood decoding of minimum decoding complexity all the time, for 16QAM, real, the imaginary part of each 16QAM symbol all have 4 kinds of possibilities respectively, it is 16 times to the most high reps of reality, imaginary part Syndicating search, complexity is high, too high to the requirement of receiver.

Again on the one hand, prior art is to sending the high order modulation technique of signal employing based on 16QAM constellation by the data stream merging transmission of different priorities, but, between two data flow under 16QAM hierarchical modulation, restriction relation is too tight, because in a 16QAM symbol, the lower QPSK symbol limited performance of power is in the higher QPSK symbol of power.When the data of high prioritized bit position are at receiver place decoding error, then the data of low priority bit must make a mistake.Thus cause retransmitting frequency increasing.

Finally, when retransmission takes place, receiver after the Soft Inform ation obtaining data retransmission, can only merge with the Soft Inform ation transmitting data first, then carries out channel decoding.This merging belongs to the merging of bit-level, merges rank lower.And merge rank lower, merge more delayed, mutual information loss larger, performance gain acquisition fewer.

Summary of the invention

For solving the problems of the technologies described above, the embodiment of the present application provides the data adaptive repeating method and device that a kind of reliability is high, decoding complexity is low.

Technical scheme is as follows:

An adaptive retransmit method for data, described method comprises:

Data receiver carries out decoding to the data received, if there is decoding error, described data receiver sends repeat requests to base station;

After described base station receives described repeat requests, in space-time coding matrices set, retransmit Criterion of Selecting according to optimum choose optimum re-transmission encoder matrix, data retransmission, new biography data and optimum preconditioning matrix numbering is sent to each relaying, the data retransmission sent described base station in a distributed fashion by each relaying and new biography data loading enter optimum re-transmission encoder matrix, are forwarded to described data receiver.

Preferably, described space-time coding matrices set is obtained by following steps:

According to the quantity of relaying, choose a line number and equal the minimum decoding complexity space-time block code MDC-QO-STBC matrix of the quantity of described relaying as basic coding matrix;

The line order of described basic coding matrix is converted, obtains space-time coding matrices set.

Preferably, described space-time coding matrices set is:

The line order of described basic coding matrix is converted in the space-time coding matrices obtained, there is the set of the space-time coding matrices composition of disturbance item absolute value.

Preferably, described optimum re-transmission Criterion of Selecting is specially:

From described space-time coding matrices set, the encoder matrix choosing the absolute value that meets distracter corresponding to the described encoder matrix distracter sum corresponding with encoder matrix when transmitting first minimum retransmits encoder matrix as optimum.

Preferably, the described data retransmission that sent described base station in a distributed fashion by each relaying and new biography data loading enter optimum re-transmission in encoder matrix, are forwarded to described data receiver and specifically comprise:

Each relaying is chosen preconditioning matrix by optimum preconditioning matrix numbering and is carried out linear process to the re-transmitted signal received from coefficient matrix set, obtains the re-transmitted signal after processing; Described re-transmitted signal is made up of data retransmission and new biography data;

Re-transmitted signal after described process is loaded into the optimum encoder matrix that retransmits and is sent to data receiver by each relaying, and the re-transmitted signal after the described process that described each relaying sends forms distributed space time block coding DSTBC matrix.

Preferably, described each relaying in a distributed fashion by base station the data retransmission sent out and new biography data be loaded into simultaneously and optimumly retransmit encoder matrix, and after being forwarded to described data receiver, described method comprises further:

After described data receiver receives re-transmitted signal, carry out decoding and obtain described data retransmission and new biography data.

Preferably, after described data receiver receives re-transmitted signal, carry out decoding and obtain described data retransmission and new biography data specifically comprise:

The described data retransmission received is carried out symbol level merging with the corresponding data transmitted first by described data receiver, adopts linear detection algorithm, obtains the data retransferred;

Described data receiver, to the single complex symbol maximum likelihood algorithm of the new biography data acquisition received, obtains described new biography data.

Preferably, the data that described data receiver receives are obtained by following steps:

Preliminary treatment is carried out to sending signal first in described base station, sends pretreated signal to each relaying;

Described each relaying carries out linear process respectively to the received signal, and then each relaying is simultaneously to the signal after described data receiver transmission processing, and the signal after described process forms distributed space time block coding DSTBC matrix.

Preferably, described transmission signal is map to standard planisphere gained after the decoding of information bit channel.

Preferably, preliminary treatment is carried out to sending signal first in described base station, sends pretreated signal specifically comprise to each relaying:

Described base station by real, the imaginary component of described transmission signal from and order arrangement;

Be multiplied by a preconditioning matrix, obtain the transmission signal of reality, imaginary part restructuring, the numbering of described transmission signal and preconditioning matrix is sent to each relaying with signalling format; The numbering of described preconditioning matrix is identical with the numbering of described relaying;

Described each relaying carries out linear process respectively to the received signal and specifically comprises:

Send signal described in described relay reception, and choose from preconditioning matrix group according to the numbering of described preconditioning matrix and number corresponding preconditioning matrix with relaying and carry out linear process to the received signal.

Disclosed herein as well is a kind of base station, described base station comprises:

Repeat requests acquisition module, for obtaining the repeat requests that data receiver sends to described base station;

Data retransmission sending module, choosing optimum re-transmission encoder matrix for retransmitting Criterion of Selecting according to optimum in space-time coding matrices set, data retransmission, new biography data and optimum preconditioning matrix being edited and released and delivering to a relaying.

Preferably, described base station comprises further:

Encoder matrix set acquisition module, for the quantity according to relaying, choose a line number and equal the MDC-QO-STBC encoder matrix of the quantity of described relaying as basic coding matrix, the line order of described basic coding matrix is converted, obtains space-time coding matrices set.

Preferably, described base station comprises further:

First pretreatment module, for carrying out preliminary treatment to sending signal first, obtaining the transmission signal of reality, imaginary part restructuring, and sending pretreated signal to each relaying.

Preferably, described first pretreatment module is specially:

Described first pretreatment module be used for by real, the imaginary component of described transmission signal from and order arrangement, be multiplied by a preconditioning matrix, obtain the transmission signal of reality, imaginary part restructuring, the numbering of described transmission signal and preconditioning matrix is sent to each relaying with signalling format; The numbering of described preconditioning matrix is identical with the numbering of described relaying.

Disclosed herein as well is a kind of relaying, described relaying comprises:

Forwarding module, for receiving data retransmission, new biography data and the optimum preconditioning matrix numbering that base station sends, and the data retransmission sent described base station in a distributed fashion and new biography data loading enter optimum re-transmission encoder matrix, are forwarded to described data receiver.

Preferably, described relaying also comprises:

First Linear processing module, sends signal first for receiving from base station, and chooses from preconditioning matrix group according to preconditioning matrix numbering and number corresponding preconditioning matrix with relaying and carry out linear process to the received signal.

Preferably, described relaying comprises:

Second Linear processing module, carries out linear process for choosing preconditioning matrix by optimum pre-coding matrix numbering from coefficient matrix set to the re-transmitted signal received.

Disclosed herein as well is a kind of data receiver UE, described receiving terminal UE comprises:

Repeat request module, for when carrying out decoding generation decoding error to the data received, sends repeat requests to base station.

Preferably, described receiving terminal UE comprises further:

Symbol level merges module, for the data retransmission of reception is carried out symbol level merging with the corresponding data transmitted first;

Linearity test module, for adopting linear detection algorithm to the data retransmission carried out after symbol level merging, obtains the data retransferred;

Maximum Likelihood Detection module, for the single complex symbol Maximum Likelihood Detection of the new biography data acquisition received, obtains new biography data.

Disclosed herein as well is a kind of adaptive retransmission device of data, described device comprises:

Data receiver, for when carrying out decoding generation decoding error to the data received, sends repeat requests to base station;

Base station, after receiving described repeat requests, retransmits Criterion of Selecting according to optimum and chooses optimum re-transmission encoder matrix, data retransmission, new biography data and optimum preconditioning matrix numbering is sent to relaying in space-time coding matrices set;

Relaying, for the data retransmission sent base station in a distributed fashion and new biography data loading being entered optimum re-transmission encoder matrix, is forwarded to described data receiver.

The beneficial effect of the application is: provide in technical scheme in the application, when occurring to retransmit, base station is chosen encoder matrix when retransmitting, that the optimum chosen according to current transient channel information self-adapting retransmits encoder matrix, thus ensure that selected encoder matrix is more suitable for current channel condition, re-transmission reliability is promoted.On the other hand, the application chooses optimum re-transmission encoder matrix owing to retransmitting Criterion of Selecting according to optimum in encoder matrix set, make receiving terminal when carrying out decoding to re-transmitted signal, detection algorithm is detected from single complex symbol ML and is converted into linearity test, the complexity of receiving terminal decoding reduces.

Again on the one hand, because the application is to sending signal for mapping to standard planisphere gained, namely QPSK modulation is adopted, therefore when not retransmitting generation, MDC-QO-STBC under QPSK modulation is carried out to single complex symbol Maximum Likelihood Detection of minimum decoding complexity, be only 4 times the most high reps of reality, imaginary part Syndicating search, complexity is very low, is easy to realize; Occur if retransmit, adopt linear detection algorithm, the performance that namely MMSE detects, ZF detects scheduling algorithm and programmable single-chip system ML algorithm, complexity significantly reduces on the original basis.

In addition, in this application owing to adopting QPSK symbol, keep independent between two data flow with different Q OS grade, namely the transmission performance of the two can not influence each other, thus carry out only carrying out partial retransmission for the wrong data flow of biography, retransmit frequency and control to very low.

Finally, and in the application, after re-transmission occurs, data retransmission and the Received signal strength transmitting data first merge in symbol rank, will much smaller than bit level merging at the mutual information loss amount of symbol level merging, and performance gain can be more remarkable.

Accompanying drawing explanation

In order to be illustrated more clearly in the embodiment of the present application or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, the accompanying drawing that the following describes is only some embodiments recorded in the application, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.

The method first embodiment flow chart that Fig. 1 provides for the application;

Fig. 2 is the schematic diagram of time-division semiduplex many relaying cooperations system;

The method second embodiment flow chart that Fig. 3 provides for the application;

The data adaptive retransmission arrangement schematic diagram that Fig. 4 provides for the application;

Fig. 5 is the embodiment of the present application base station schematic diagram.

Embodiment

The embodiment of the present application provides the data adaptive repeating method and device that a kind of reliability is high, decoding complexity is low.Technical scheme in the application is understood better in order to make those skilled in the art person, below in conjunction with the accompanying drawing in the embodiment of the present application, technical scheme in the embodiment of the present application is clearly and completely described, obviously, described embodiment is only some embodiments of the present application, instead of whole embodiments.Based on the embodiment in the application, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all should belong to the scope of the application's protection.

First the adaptive retransmit method of a kind of data of the application is described.

In broadband wireless communications, the data flow of different Q OS grade is merged by the technology such as superimposed coding, hierarchical modulation and sends by classified service, under the prerequisite of the multiple data flow of protection priority separately, realizes transmitting, to save system resource simultaneously.For choosing of the encoder matrix used during transmission, be will average out between full diversity, two-forty, moderate decoding complexity.We are introduced conventional space-time coding matrices below.

Orthogonal space-time block code (Orthogonal STBC, O-STBC) can meet full diversity and linear decoding complexity, but when sending out antenna number and being greater than 2, then can not ensure that full rate is transmitted simultaneously.With QO-STBC (the quasi-Orthogonal Space Time Block Code of constellation rotation, pseudo-orthogonal space-time block code) then relax the completely orthogonal requirement of all symbols of O-STBC, full rate and full diversity can be obtained simultaneously, but need to adopt ML decoding at nonopiate intersymbol, compared to the linear decoding of O-STBC, complexity strengthens.MDC-QO-STBC belongs to a class of QO-STBC, be characterized in orthogonal between each complex symbol in code word, and it is nonopiate between the inner reality of every complex symbol, imaginary part, therefore maximum likelihood (ML) decoding only need be carried out a complex symbol inside, be called " single complex symbol ML decoding " (Single Complex Symbol MLDecoding, SCSML), therefore MDC-QO-STBC is in the STBC matrix of all non-linear decoding, the class code word that decoding complexity is minimum.

In prior art, there is a kind of repeating method for classified service.This side's ratio juris is: eNB is divided into two stages with the communication between UE.First stage; eNB place sends signal to Relay; adopt hierarchical modulation technology by the data stream merging transmission of different priorities; high-priority traffic is mapped to high protection bit; the data stream of low priority is to low protection bit; thus the data flow of different priorities is transmitted simultaneously, and keep respective protection class.Hierarchical modulation based on qam constellation is a kind of main flow way.In 16QAM constellation, high-priority traffic is mapped as quadrant bit (first 2), and low-priority data stream is mapped as the bit (latter 2) in same quadrant.Because the distance between quadrant is very large, so high-priority traffic is not easy erroneous judgement.And under the condition that energy is certain, the distance having widened bit between quadrant means the judging distance reducing quadrant Nepit position, thereby produce different protection class.In addition, qam constellation can also distinguish the priority of multithread from symbol rank, and such as a 16QAM symbol can be understood as the time domain superposition that two power ratios are the QPSK symbol of 4: 1.First QPSK symbol is that front dibit maps to QPSK constellation gained, the rear dibit of second corresponding 16QAM symbol of QPSK symbol, but not employing standard QPSK planisphere, but determine according to first concrete quadrant position of QPSK symbol, i.e. a kind of planisphere of corresponding second the QPSK symbol of each quadrant position difference.

Second stage, each Relay forwards with amplification forwarding (AF) form the eNB received to UE simultaneously and signaled, and transmission form is wherein a line of selected space-time coding matrices.

At receiver place, adopt the decoding algorithm of MDC-QO-STBC, i.e. single complex symbol ML decoding, solve the data of high and low priority two stream simultaneously.When having first-class making a mistake in two streams of classification, eNB retransmits it.Keep original priority of data retransmission constant, and the new biography data of another one data flow carry out hierarchical modulation, realize merging transmission.At each Relay place, carry out AF forwarding according to original encoder matrix form.After receiver receives retransmission frame data, first carry out MDC-QO-STBC decoding, obtain data retransmission and new biography data, data retransmission is carried out soft demodulation, obtain Soft Inform ation, thus Soft Inform ation when transmitting first with these data merges, and then carries out channel decoding.

The merging transmission of prior art owing to adopting the mode of 16QAM high order modulation to realize data, two data flow are comprised in each 16QAM symbol, therefore the restriction relation between two data flow is too tight, the lower data flow limited performance of power is in the higher data flow of power, if high prioritized bit position is at receiver place decoding error, then low priority bit must make a mistake, thus causes retransmitting frequency increasing.In addition, when retransmitting, still adopting fixing encoder matrix, not considering whether encoder matrix is still applicable to current instantaneous channel state, and reliability is not high.In addition, the interpretation method complexity of prior art is too high, too high to the requirement of receiver.When retransmitting generation, the Soft Inform ation of data retransmission and the Soft Inform ation transmitted first are merged, information loss is comparatively large, obtains performance gain less.

The application's proposition a kind of data adaptive repeating method, goes for the data re-transmission of classified service.When the method that the application provides can be applied to distributed space in treatment system.First in many relaying cooperations system, the classification transmission of multi-stream data is realized by the distributed space-time block code of minimum decoding complexity (MDC-QO-DSTBC), and then provide a kind of adaptive partial retransmission method, can ensure that the data flow retransmitted realizes full diversity, two-forty, linear decoding complexity, can ensure that again the re-transmission of this data flow does not affect the real-time Transmission of another data flow.

See Fig. 1, it is the method first embodiment flow chart that the application provides.

S101, data receiver carries out decoding to the data received, if there is decoding error, described data receiver sends repeat requests to base station.

S102, after described base station receives described repeat requests, in space-time coding matrices set, retransmit Criterion of Selecting according to optimum choose optimum re-transmission encoder matrix, data retransmission, new biography data and optimum preconditioning matrix numbering is sent to each relaying, the data retransmission sent described base station in a distributed fashion by each relaying and new biography data loading enter described optimum and retransmit in encoder matrix, are forwarded to described data receiver.

The method provided below in conjunction with accompanying drawing the embodiment of the present application describes in detail.

See Fig. 2, it is the schematic diagram of time-division semiduplex many relaying cooperations system.

Time-division semiduplex many relaying cooperations system, by 1 eNB, 1 UE, and K Relay composition, as shown in Figure 2.Wherein each node all configures single antenna, and hold mark level is synchronous.If h _kand g _krepresent eNB respectively to a kth via node R _kand R _kchannel fading coefficient between UE, independent same distribution (i.i.d.) in (0,1), and numerical value remains unchanged within the transmission time of T symbol.ENB can know h according to channel reciprocity _k, simultaneously can according to R _kfeedback know g _k, and R _konly there is g _kinformation.

Be the cooperative system of 4 for relaying number below, the method that the application provides is described.The data flow two with different priorities is respectively loaded into same MDC-QO-STBC matrix, realizes distributed transmission simultaneously.In addition, consider that wherein only there is a data flow lays particular emphasis on transmission quality, supports to retransmit; And another data flow lays particular emphasis on real-time, do not support the situation retransmitted, provide adaptive partial retransmission method.

The method second embodiment flow chart that Fig. 3 provides for the application.

In classified service, if data flow 1 support retransmits, data flow 2 is not supported to retransmit, and the two respectively gives priority in performance and delay requirement, to adapt to different business.For the 4 relaying distributed collaboration systems based on MDC-QO-DSTBC, eNB signals x=[x ₁, x ₂, x ₃, x ₄] ^t, then the data of data flow 1, data flow 2 are mapped to former and later two symbols x respectively _stream1=[x ₁, x ₂] ^t, x _stream2=[x ₃, x ₄] ^t.Thus when each relaying place unitary construction DSTBC, realize the classification of stream 1, stream 2 to merge transmission.Here, keep independent between the data flow of two different priorities, the transmission performance of the two can not influence each other.

Below the transmitting procedure first of data is introduced.

S301, preliminary treatment is carried out to sending signal first in described base station, sends pretreated signal to each relaying.

Preferably, described transmission signal maps to standard planisphere gained after being the decoding of information bit channel, is QPSK symbol.

Preferably, described step S301 is specially:

Base station by real, the imaginary component of described transmission signal from and order arrangement, be multiplied by a preconditioning matrix, obtain the transmission signal of reality, imaginary part restructuring, obtain the encoder matrix sending signal, the signal power normalization that base station is sent.Described base station by the encoder matrix of described transmission signal and each row of described encoder matrix corresponding preconditioning matrix numbering be sent to each relaying with signalling format.The numbering of described preconditioning matrix is identical with the numbering of described relaying.

Specific to the present embodiment, in the transmission first of data flow 1, data flow 2, base station eNB sends signal with the forms of broadcasting to each relaying Relay, and described transmission signal maps to standard planisphere gained after being the decoding of information bit channel, is QPSK symbol.

Base station eNB successively using Q symbol as a pretreatment unit, with x=[x ₁, x ₂... x _q] ^tfor example, by real for element each in x imaginary component from also order arrangement, obtain wherein () ^r, () ⁱrepresent real, the imaginary part of complex symbol respectively.For following process is done with the preconditioning matrix P that a size is Q × 2Q:

$\tilde{x}={\left(P\hat{x}\right)}^T---\left(1\right)$

Described preconditioning matrix P makes the complex symbol of transmission be split and recombinate, and can ensure namely to meet the signal power normalization that base station sends simultaneously:

$E\left[\tilde{x}{\tilde{x}}^H\right]=1$

Base station eNB sends to each relaying Relay r _kon reception vector be:

$r_k=h_k\tilde{x}+n_k---\left(2\right)$

Wherein n _kfor additive white Gaussian noise, submit to (0,1).In this hypothesis transmission signal power of eNB and the equal normalization of received signal power of UE, and the signal transmitting power of each Relay is equal, is 1/K.

To sum up, in the transmission first of data flow 1 and data flow 2, any one MDC-QO-STBC code word of base station selection as the basic coding matrix of DSTBC, and carries out preliminary treatment to it, and preconditioning matrix group # corresponding for matrix rows is sent to each Relay with signalling format.

Step S302, described each relaying carries out linear process respectively to the received signal, and then each relaying is simultaneously to the signal after described data receiver transmission processing, and the signal after described process forms distributed space time block coding DSTBC matrix.

Concrete, described step S302 comprises:

S302A, described relaying receives from base station and sends signal, and chooses from preconditioning matrix group according to described preconditioning matrix numbering and number corresponding preconditioning matrix with relaying and carry out linear process to the received signal.

Because system works is in AF pattern, Relay is linear operation to the process of signal.R _k(k=1,2 ... K) coefficient matrix { U that a group is used for carrying out respective Received signal strength rk linear process is configured with respectively _k, V _k, matrix size is Q × T.

Concrete, in the embodiment of the present application, be that the basic coding matrix using MDC-QO-STBC as DSTBC is put into.Provide N below _tmDC-QO-STBC code word example when=4.

Wherein, suppose that G matrix is that one comprises Q complex symbol, size is N _tthe matrix G of × T, its transmission rate is R _sTBC=Q/T.G can form represent as follows:

$G=\underset{q=1}{\overset{Q}{\mathrm{\Σ}}}(x_q^R{A}_q+x_q^I{B}_q)---\left(3\right)$

Wherein for a complex symbol of G matrix, and { A _q, B _qbe respectively in fact, the diffusion matrix of imaginary part, size is N _t× T.

Also can be expressed as:

$G=\left(\begin{array}{cccc}{x}_1^R+{\mathrm{jx}}_3^R& -x_2^R+{\mathrm{jx}}_4^R& -x_1^I+{\mathrm{jx}}_3^I& x_2^I+{\mathrm{jx}}_4^I\\ x_2^R+{\mathrm{jx}}_4^R& x_1^R-{\mathrm{jx}}_3^R& -x_2^I+{\mathrm{jx}}_4^I& -x_1^I-{\mathrm{jx}}_3^I\\ -x_1^I+{\mathrm{jx}}_3^I& x_2^I+{\mathrm{jx}}_4^I& x_1^R+{\mathrm{jx}}_3^R& -x_2^R+{\mathrm{jx}}_4^R\\ -x_2^I+{\mathrm{jx}}_4^I& -x_1^I-{\mathrm{jx}}_3^I& x_2^R+{\mathrm{jx}}_4^R& x_1^R-{\mathrm{jx}}_3^R\end{array}\right)---\left(4\right)$

For above-mentioned G matrix, a kth relaying R _kpreconditioning matrix group { U _k, V _kbe taken as { E _k, F _k(k=1,2,3,4), namely relaying is chosen according to described preconditioning matrix numbering and is numbered corresponding preconditioning matrix with relaying and carry out linear process to the received signal from preconditioning matrix group.

In the embodiment of the present application, each cooperative relaying is equivalent to a transmitting antenna of DSTBC matrix, and the transmission signal unitary construction of all relayings goes out an equivalent MDC-QO-STBC.Now, the source node preconditioning matrix P of DSTBC and via node preconditioning matrix group { U _k, V _k, all can by N _tthe MDC-QO-STBC encoder matrix of=K extracts and obtains.For G matrix (4), if four of G matrix the first row elements are followed successively by then have:

$\tilde{x}=[{\tilde{x}}_1,{\tilde{x}}_2,{\tilde{x}}_3,{\tilde{x}}_4]={\left(P\hat{x}\right)}^T={\left(P{[x_1^R,x_1^I,...x_4^R,x_4^I]}^T\right)}^T---\left(5\right)$

Thus obtain preconditioning matrix P:

$P=\left[\begin{array}{cccccccc}1& 0& 0& 0& j& 0& 0& 0\\ 0& 0& -1& 0& 0& 0& j& 0\\ 0& -1& 0& 0& 0& j& 0& 0\\ 0& 0& 0& 1& 0& 0& 0& j\end{array}\right]---\left(6\right)$

G matrix is then converted to following form:

$\tilde{G}=\left(\begin{array}{cccc}{\tilde{x}}_1& {\tilde{x}}_2& {\tilde{x}}_3& {\tilde{x}}_4\\ -{{\tilde{x}}_2}^{*}& {{\tilde{x}}_1}^{*}& -{{\tilde{x}}_4}^{*}& {{\tilde{x}}_3}^{*}\\ {\tilde{x}}_3& {\tilde{x}}_4& {\tilde{x}}_1& {\tilde{x}}_2\\ -{{\tilde{x}}_4}^{*}& {{\tilde{x}}_3}^{*}& -{{\tilde{x}}_2}^{*}& {{\tilde{x}}_1}^{*}\end{array}\right)---\left(7\right)$

Will every a line respectively with f form represents, then with the coefficient matrix group { E that n-th (n=1,2,3,4) row is corresponding _n, F _nas follows, wherein 0 ₄represent that size is the full 0 matrix of 4 × 4.Like this by R _kpreconditioning matrix group { U _k, V _kbe taken as { E _n, F _n.

$E_1=\left[\begin{array}{cccc}1& 0& 0& 0\\ 0& 1& 0& 0\\ 0& 0& 1& 0\\ 0& 0& 0& 1\end{array}\right]F_2=\left[\begin{array}{cccc}0& 1& 0& 0\\ -1& 0& 0& 0\\ 0& 0& 0& 1\\ 0& 0& -1& 0\end{array}\right]$

$E_3=\left[\begin{array}{cccc}0& 0& 1& 0\\ 0& 0& 0& 1\\ 1& 0& 0& 0\\ 0& 1& 0& 0\end{array}\right]F_4=\left[\begin{array}{cccc}0& 0& 0& 1\\ 0& 0& -1& 0\\ 0& 1& 0& 0\\ -1& 0& 0& 0\end{array}\right]---\left(8\right)$

F ₁＝E ₂＝F ₃＝E ₄＝0 ₄

Step S302B, each relaying is simultaneously to the signal after receiving terminal transmission processing, and the signal after described process forms distributed space time block coding DSTBC matrix.

Concrete, with () ^*represent the conjugation of vector, represent R _knoise power, then R _ktransmission signal be:

$t_k=\frac{1}{\sqrt{K({\left|h_k\right|}^2+{\mathrm{\σ}}_{R_k}^2)}}\{r_k{U}_k+r_k^{*}{V}_k\}---\left(9\right)$

S303, data receiver receives the signal sent by described relaying, carries out decoding to described signal.

Suppose w ^- the additive white Gaussian noise that (0,1) is UE place, then the Received signal strength at data receiver UE place is:

$y=\underset{k=1}{\overset{K}{\mathrm{\Σ}}}{g}_k{t}_k+w---\left(10\right)$

(9) are substituted in (10), can obtain:

$y=\frac{1}{\sqrt{K}}[\frac{g_1}{\sqrt{({\left|h_1\right|}^2+{\mathrm{\σ}}_{R_1}^2)}}\·\·\·\frac{g_K}{\sqrt{({\left|h_K\right|}^2+{\mathrm{\σ}}_{R_K}^2)}}]X\left(x\right)+\mathrm{\η}---\left(11\right)$

In above formula, equivalent STBC matrix X (x) and equivalent noise η expression formula are respectively:

$X\left(x\right)={[{[h_1\tilde{x}{U}_1+{\left(h_1\tilde{x}\right)}^{*}{V}_1]}^T\·\·\·{[h_K\tilde{x}{U}_k+{\left(h_K\tilde{x}\right)}^{*}{V}_K]}^T]}^T---\left(12\right)$

$\mathrm{\η}=\frac{1}{\sqrt{K}}\underset{k=1}{\overset{K}{\mathrm{\Σ}}}\frac{g_k}{\sqrt{({\left|h_k\right|}^2+{\mathrm{\σ}}_{R_k}^2)}}(n_k{U}_k+n_k^{*}{V}_k)+w---\left(13\right)$

According to for the encoder matrix of DSTBC, channel fading coefficient between the eNB to Relay of X (x) in (13) is extracted, then has:

$X\left(x\right)=\left[\begin{array}{cccc}{h}_1& & & \\ & {h_2}^{*}& & \\ & & h_3& \\ & & & {h_4}^{*}\end{array}\right]\tilde{G}\left(x\right)---\left(14\right)$

(11) be converted into:

$y=\frac{1}{\sqrt{K}}\left[\begin{array}{cc}\frac{g_1{h}_1}{\sqrt{({\left|h_1\right|}^2+{\mathrm{\σ}}_{R_1}^2)}}& \frac{g_2{h_2}^{*}}{\sqrt{({\left|h_2\right|}^2+{\mathrm{\σ}}_{R_2}^2)}}\·\·\·\\ \·\·\·\frac{g_3{h}_3}{\sqrt{({\left|h_3\right|}^2+{\mathrm{\σ}}_{R_3}^2)}}& \frac{g_4{h_4}^{*}}{\sqrt{({\left|h_4\right|}^2+{\mathrm{\σ}}_{R_4}^2)}}\end{array}\right]\tilde{G}\left(x\right)+\mathrm{\η}---\left(15\right)$

Wherein equivalent channel transfer matrix H _efor:

$H_e=\left[\begin{array}{cc}\frac{g_1{h}_1}{\sqrt{({\left|h_1\right|}^2+{\mathrm{\σ}}_{R_1}^2)}}& \frac{g_2{h_2}^{*}}{\sqrt{({\left|h_2\right|}^2+{\mathrm{\σ}}_{R_2}^2)}}\·\·\·\\ \·\·\·\frac{g_3{h}_3}{\sqrt{({\left|h_3\right|}^2+{\mathrm{\σ}}_{R_3}^2)}}& \frac{g_4{h_4}^{*}}{\sqrt{({\left|h_4\right|}^2+{\mathrm{\σ}}_{R_4}^2)}}\end{array}\right]---\left(16\right)$

If equivalent received signals is:

$({\left(H_e^I\right)}^T*Y^I)={\left[\begin{array}{cccccccc}{\left(y_1^R\right)}^I& {\left(y_1^I\right)}^I& {\left(y_2^R\right)}^I& {\left(y_2^I\right)}^I& y_3^R& y_3^I& y_4^R& y_4^I\end{array}\right]}^T,$ Then overall effective transmission equation is as follows:

$\left[\begin{array}{c}{\left(y_1^R\right)}^I\\ {\left(y_1^I\right)}^I\\ {\left(y_2^R\right)}^I\\ {\left(y_2^I\right)}^I\\ y_3^R\\ y_3^I\\ y_4^R\\ y_4^I\end{array}\right]=\left[\begin{array}{cccccccc}{a}^I& I^I& 0& 0& 0& 0& 0& 0\\ I^I& a^I& 0& 0& 0& 0& 0& 0\\ 0& 0& a^I& I^I& 0& 0& 0& 0\\ 0& 0& I^I& a^I& 0& 0& 0& 0\\ 0& 0& 0& 0& a^I& -I^I& 0& 0\\ 0& 0& 0& 0& -I^I& a^I& 0& 0\\ 0& 0& 0& 0& 0& 0& a^I& -I^I\\ 0& 0& 0& 0& 0& 0& -I^I& a^I\end{array}\right]\left[\begin{array}{c}{x}_1^R\\ x_1^I\\ x_2^R\\ x_2^I\\ x_3^R\\ x_3^I\\ x_4^R\\ x_4^I\end{array}\right]+\left[{\left(H_e^I\right)}^T{n}_{\mathrm{equ}}^I\right]---\left(17\right)$

A ⁱ, I ⁱrepresent that the power gain and interference of transmitting corresponding real number symbol are first at H respectively _cin, the first two 2*2 submatrix corresponds to the equivalent channel correlation matrix of data flow 1, and latter two 2*2 submatrix corresponds to the equivalent channel correlation matrix of data flow 2.Because former and later two submatrixs are mutually orthogonal, therefore formula (17) can be carried out linear decomposition, obtain the effective transmission equation of stream 1 and stream 2 respectively.For stream 1, it transmits equivalent received signals first and is $Y_{\mathrm{stream}1}^I={\left[\begin{array}{cccc}{y}_1^R& y_1^I& y_2^R& y_2^I\end{array}\right]}^T,$ Its effective transmission equation can be write as:

$\left[\begin{array}{c}{\left(y_1^R\right)}^I\\ {\left(y_1^I\right)}^I\\ {\left(y_2^R\right)}^I\\ {\left(y_2^I\right)}^I\end{array}\right]=\left[\begin{array}{cccc}{a}^I& I^I& 0& 0\\ I^I& a^I& 0& 0\\ 0& 0& a^I& I^I\\ 0& 0& I^I& a^I\end{array}\right]\left[\begin{array}{c}{x}_1^R\\ x_1^I\\ x_2^R\\ x_2^I\end{array}\right]+{\left[{\left(H_e^I\right)}^T{n}_{\mathrm{equ}}^I\right]}_{\mathrm{first}4\mathrm{rows}}---\left(18\right)$

Wherein, the equivalent channel correlation matrix flowing 1 is:

$H_{c,\mathrm{stream}1}^I=\left[\begin{array}{cccc}{a}^I& I^I& 0& 0\\ I^I& a^I& 0& 0\\ 0& 0& a^I& I^I\\ 0& 0& I^I& a^I\end{array}\right]---\left(19\right)$

For stream 2, its equivalent received signals is $Y_{\mathrm{stream}2}={\left[\begin{array}{cccc}{y}_3^R& y_3^I& y_4^R& y_4^I\end{array}\right]}^T,$ Then its effective transmission equation can be write as:

$\left[\begin{array}{c}{y}_3^R\\ y_3^I\\ y_4^R\\ y_4^I\end{array}\right]=\left[\begin{array}{cccc}{a}^I& {-I}^I& 0& 0\\ -I^I& a^I& 0& 0\\ 0& 0& a^I& {-I}^I\\ 0& 0& -I^I& a^I\end{array}\right]\left[\begin{array}{c}{x}_3^R\\ x_3^I\\ x_4^R\\ x_4^I\end{array}\right]+{\left[{\left(H_e^I\right)}^T{n}_{\mathrm{equ}}^I\right]}_{\mathrm{last}4\mathrm{rows}}---\left(20\right)$

DSTBC encoder matrix is decoded, is equivalent to detect formula (18).Different detection algorithms is adopted according to the orthogonality of encoder matrix.When encoder matrix G is O-STBC, H _cfor diagonal matrix, adopt linear algorithm can detect each real number symbol; When encoder matrix G is QO-STBC, H _cfor Block diagonal matrix, orthogonal between different sub-block, and nonopiate between the real number symbol of each sub-block inside, therefore need to carry out ML detection for each sub-block.And for MDC-QO-STBC, its equivalent channel correlation matrix H _cfor Block diagonal matrix, each sub-block equal and opposite in direction, is 2 × 2, corresponds respectively to real, the imaginary part of a complex symbol, and orthogonal between different complex symbol.Like this, ML detects and only need carry out for real, imaginary part two real number symbols of every complex symbol, and therefore MDC-QO-STBC becomes the code word that in QO-STBC, decoding complexity is minimum.

Here, single complex symbol Maximum Likelihood Detection of minimum decoding complexity is adopted to carry out decoding to MDC-QO-STBC.

S304, when data receiver carries out decoding generation decoding error to the data received, receiving terminal sends repeat requests to base station.

S305, after described base station receives described repeat requests, in space-time coding matrices set, retransmit Criterion of Selecting according to optimum choose optimum re-transmission encoder matrix, data retransmission, new biography data and optimum preconditioning matrix numbering is sent to each relaying, the data retransmission sent described base station in a distributed fashion by each relaying and new biography data loading enter optimum re-transmission in encoder matrix, are forwarded to described data receiver.

Concrete, the optimum preconditioning matrix corresponding with each relaying that the data of the data retransferred, new transmission and described optimum re-transmission encoder matrix determine is numbered and is sent to each relaying by described base station, each relaying is chosen preconditioning matrix by optimum preconditioning matrix numbering and is carried out linear process to the re-transmitted signal received from coefficient matrix set, and described re-transmitted signal is made up of data retransmission and new biography data described re-transmitted signal; Re-transmitted signal after process is sent to receiving terminal UE by described each relaying, and the re-transmitted signal after the process that described each relaying sends forms distributed space time block coding DSTBC matrix.

Concrete, when retransmitting generation, base station just needs the data of data and the new transmission retransferred to be loaded in same encoder matrix.At this moment, eNB becomes at the transmission signal of retransmission frame: x=[x ₁, x ₂, x ₅, x ₆] ^t, wherein, x _stream1=[x ₁, x ₂] ^tfor the data retransmission of data flow 1, and x ' _stream2=[x ₅, x ₆] ^tbe then the new data of data flow 2 within when the current frame.

Encoder matrix when transmitting first is determined, and during re-transmission, eNB, then in the candidate collection of a series of encoder matrix, carries out self adaptation by Criterion of Selecting to DSTBC and chooses.

Preferably, described space-time coding matrices set is obtained by following steps:

According to the quantity of relaying, choose a line number and equal the minimum decoding complexity space-time block code MDC-QO-STBC encoder matrix of the quantity of described relaying as basic coding matrix, the line order of described basic coding matrix is converted, obtains encoder matrix set.

Preferably, described space-time coding matrices set is convert in the space-time coding matrices obtained the line order of described basic coding matrix, has the set of the encoder matrix composition of disturbance item absolute value.

Preferably, described optimum re-transmission Criterion of Selecting is specially:

From space-time coding matrices set, the encoder matrix choosing the absolute value that meets distracter corresponding to the described encoder matrix distracter sum corresponding with encoder matrix when transmitting first minimum retransmits encoder matrix as optimum.

Below the acquisition methods of encoder matrix set is described in detail with the optimum Criterion of Selecting that retransmits.

Be the cooperative system of 4 for relaying number, first choose a line number be 4 MDC-QO-STBC encoder matrix be basic coding matrix, with matrix is example, if by { the E of its n-th line _n, F _nas the capable coefficient matrix group of m (m ≠ n), can realize in the n-th, m capable exchange.Like this, if at set { { E _n, F _n, n=1, in 2,3,4}, an optional element is as R _kpreconditioning matrix group { U _k, V _k, and do not require to choose the numbering of element to be only k, R _ktransmission signal can present 4 kinds of forms, respectively corresponding every a line in matrix.Thus, be that 4 Relay exist coefficient matrix group set { { E _n, F _n, n=1, chooses preconditioning matrix group in 2,3,4} respectively, total plant possibility, construct DSTBC encoder matrix using the numbering of Relay as line number, mean existence plant the candidate code matrix that MDC-QO-STBC code word can be used as DSTBC, comprise matrix and its line order is converted to the code word obtained.

This plant encoder matrix, equivalent channel correlation matrix H _cform is identical, is 8 × 8 pieces of diagonal angle real number matrix, and H _cthe power gain part of middle signal is all identical, and for distracter absolute value, the H of every 4 kinds of code words _cmiddle distracter absolute value is identical, thus co-exists in 6 kinds of different distracter absolute value expression formulas, and this expression formula is relevant with transient channel fading characteristic.Now DSTBC candidate code matrix from plant and be reduced to 6 kinds, only the code word with disturbance item absolute value expression formula is retained.

Table 1 provides with line order mapping mode corresponding to 6 kinds of candidate code matrixes, and be called " candidate's line order ", the four lines that four numerical value under often kind of mode characterize DSTBC successively exists line number in matrix.Such as mode 2. under, the 1st of candidate code matrix, 2 row are respectively matrix the 1st, 2 row, and the 3rd, 4 row are then respectively the 4th, 3 row.

Table 14 cooperative relayings-candidate row sequence table

Mode	①	②	③	④	⑤	⑥
							Line order	1 2 3 4	1 2 4 3	1 3 2 4	2 1 3 4	2 1 4 3	3 1 4 2

For 6 kinds of candidate's line orders, corresponding 6 kinds of equivalent channel transfer matrix H respectively _{e, m}(m=1,2 ... 6), in mode 2., have:

$H_{e,2}=\left[\begin{array}{cc}\frac{g_1{h}_1}{\sqrt{({\left|h_1\right|}^2+{\mathrm{\σ}}_{R_1}^2)}}& \frac{g_2{h_2}^{*}}{\sqrt{({\left|h_2\right|}^2+{\mathrm{\σ}}_{R_2}^2)}}\·\·\·\\ \·\·\·\frac{g_4{h}_4}{\sqrt{({\left|h_4\right|}^2+{\mathrm{\σ}}_{R_4}^2)}}& \frac{g_3{h_3}^{*}}{\sqrt{({\left|h_3\right|}^2+{\mathrm{\σ}}_{R_3}^2)}}\end{array}\right]---\left(21\right)$

By H _{e, m}(m=1,2 ... 6) respectively as be updated to in, can obtain with the corresponding distracter absolute value expression formula I of 6 kinds of candidate code matrixes _m(m=1,2 ... 6).Same h, g are relevant for distracter order of magnitude, therefore can using distracter absolute value | and I| is as the benchmark of these codeword performance of assessment.

During owing to transmitting first, the transmission line order numbering of each Relay is determined, is set to index _i, corresponding distracter is set to | I ⁱ|, then when retransmitting, the self adaptation that eNB carries out optimum DSTBC matrix is chosen, if the line order chosen is numbered index _iI, then corresponding distracter is set to | I ^iI|.

At given instantaneous channel activity h, under g, compare the absolute value expression formula of the corresponding distracter sum of 6 kinds of candidate code matrixes | I ⁱ+ (I ^iI) _m| (m=1,2 ... 6), thus select | I ⁱ+ (I ^iI) _m| the minimum code word of value is as the optimum code matrix retransmitting DSTBC, and corresponding line order is transformed to optimum line order, thus obtains numbering index _iI.

Optimum line order numbering index _iIby eNB retransmit time send to each Relay with signalling format, each Relay so coefficient matrix group set { { E _n, F _n, n=1, chooses preconditioning matrix group in 2,3,4} respectively, like this, distracter sum absolute value minimum DSTBC encoder matrix structure complete.Due to now | I ⁱ+ I ^iI| value is enough little, can be ignored, thus adopts linear decoding can realize the performance of single complex symbol ML decoding, and decoding complexity is obviously reduced.

S306, after described receiving terminal receives retransmission frame data, carries out the data that decoding obtains data and the new transmission retransferred.

Preferably, the data retransferred described in acquisition are carried out symbol level merging with the corresponding data transmitted first by described receiving terminal, adopt linear detection algorithm, obtain the data retransferred.

After re-transmission, receiver place equivalent received signals is wherein front 4 row correspond to the Received signal strength of stream 1, are set to rear 4 row correspond to stream 2, are set to Y ' _stream2.Overall effective transmission equation is as follows:

$\left[\begin{array}{c}{\left(y_1^R\right)}^{\mathrm{II}}\\ {\left(y_1^I\right)}^{\mathrm{II}}\\ {\left(y_2^R\right)}^{\mathrm{II}}\\ {\left(y_2^I\right)}^{\mathrm{II}}\\ y_5^R\\ y_5^I\\ y_6^R\\ y_6^I\end{array}\right]=\left[\begin{array}{cccccccc}{a}^{\mathrm{II}}& I^{\mathrm{II}}& 0& 0& 0& 0& 0& 0\\ I^{\mathrm{II}}& a^{\mathrm{II}}& 0& 0& 0& 0& 0& 0\\ 0& 0& a^{\mathrm{II}}& I^{\mathrm{II}}& 0& 0& 0& 0\\ 0& 0& I^{\mathrm{II}}& a^{\mathrm{II}}& 0& 0& 0& 0\\ 0& 0& 0& 0& a^{\mathrm{II}}& -I^{\mathrm{II}}& 0& 0\\ 0& 0& 0& 0& -I^{\mathrm{II}}& a^{\mathrm{II}}& 0& 0\\ 0& 0& 0& 0& 0& 0& a^{\mathrm{II}}& -I^{\mathrm{II}}\\ 0& 0& 0& 0& 0& 0& -I^{\mathrm{II}}& a^{\mathrm{II}}\end{array}\right]\left[\begin{array}{c}{x}_1^R\\ x_1^I\\ x_2^R\\ x_2^I\\ x_5^R\\ x_5^I\\ x_6^R\\ x_6^I\end{array}\right]+\left[{\left(H_e^{\mathrm{II}}\right)}^T{n}_{\mathrm{equ}}^{\mathrm{II}}\right]---\left(22\right)$

For the re-transmitted signal of stream 1 and the new biography signal of stream 2, receiving terminal carries out differentiating and processing.

Convection current 1, by the Received signal strength of twice transmission with carry out symbol level merging.Here be that re-transmitted signal is carried out symbol level merging with the corresponding data transmitted first, the described data transmitted first are saved when transmitting first, concrete, can arrange a data storage cell for preserving the data transmitted first.

$Y_{\mathrm{stream}1}^I+Y_{\mathrm{stream}1}^{\mathrm{II}}$

$=(H_{c,\mathrm{stream}1}^I+H_{c,\mathrm{stream}1}^{\mathrm{II}})x_{\mathrm{stream}1}+{[{\left(H_e^I\right)}^T{n}_{\mathrm{equ}}^I+{\left(H_e^{\mathrm{II}}\right)}^T{n}_{\mathrm{equ}}^{\mathrm{II}}]}_{\mathrm{first}4\mathrm{rows}}---\left(23\right)$

That is:

$\left[\begin{array}{c}{\left(y_1^R\right)}^I+{\left(y_1^R\right)}^{\mathrm{II}}\\ {\left(y_1^I\right)}^I+{\left(y_1^I\right)}^{\mathrm{II}}\\ {\left(y_2^R\right)}^I+{\left(y_2^R\right)}^{\mathrm{II}}\\ {\left(y_2^I\right)}^I+{\left(y_2^I\right)}^{\mathrm{II}}\end{array}\right]=\left[\begin{array}{cccc}{a}^I+a^{\mathrm{II}}& I^I+I^{\mathrm{II}}& 0& 0\\ I^I+I^{\mathrm{II}}& a^I+a^{\mathrm{II}}& 0& 0\\ 0& 0& a^I+a^{\mathrm{II}}& I^I+I^{\mathrm{II}}\\ 0& 0& I^I+I^{\mathrm{II}}& a^I+a^{\mathrm{II}}\end{array}\right]\left[\begin{array}{c}{x}_1^R\\ x_1^I\\ x_2^R\\ x_2^I\end{array}\right]+{[{\left(H_e^I\right)}^T{n}_{\mathrm{equ}}^I+{\left(H_e^{\mathrm{II}}\right)}^T{n}_{\mathrm{equ}}^{\mathrm{II}}]}_{\mathrm{first}4\mathrm{rows}}---\left(24\right)$

Equivalent channel correlation matrix after then merging becomes:

$H_{c,\mathrm{stream}1}^{I+\mathrm{II}}=\left[\begin{array}{cccc}{a}^I+a^{\mathrm{II}}& I^I+I^{\mathrm{II}}& 0& 0\\ I^I+I^{\mathrm{II}}& a^I+a^{\mathrm{II}}& 0& 0\\ 0& 0& a^I+a^{\mathrm{II}}& I^I+I^{\mathrm{II}}\\ 0& 0& I^I+I^{\mathrm{II}}& a^I+a^{\mathrm{II}}\end{array}\right]---\left(25\right)$

At given instantaneous channel activity h, under g, compare the absolute value expression formula of the corresponding distracter sum of 6 kinds of candidate code matrixes | I ⁱ+ (I ^iI) _m| (m=1,2 ... 6), thus select | I ⁱ+ (I ^iI) _m| the minimum code word of value is as the optimum code matrix retransmitting DSTBC, and corresponding line order is transformed to optimum line order, thus obtains numbering index _iI.

Optimum line order numbering index _iIby eNB retransmit time send to each Relay with signalling format, each Relay so coefficient matrix group set { { E _n, F _n, n=1, chooses preconditioning matrix group in 2,3,4} respectively, like this, distracter sum absolute value minimum DSTBC encoder matrix structure complete.Due to now | I ⁱ+ I ^iI| value is enough little, can be ignored, thus adopts linear decoding can realize the performance of single complex symbol ML decoding, and decoding complexity is obviously reduced.

And for stream 2, i.e. the data of new transmission then do not relate to merging, single complex symbol maximum likelihood algorithm is adopted to carry out decoding, still according to following equivalent transmission equation decoding:

$\left[\begin{array}{c}{y}_5^R\\ y_5^I\\ y_6^R\\ y_6^I\end{array}\right]=\left[\begin{array}{cccc}{a}^{\mathrm{II}}& {-I}^{\mathrm{II}}& 0& 0\\ -I^{\mathrm{II}}& a^{\mathrm{II}}& 0& 0\\ 0& 0& a^{\mathrm{II}}& {-I}^{\mathrm{II}}\\ 0& 0& -I^{\mathrm{II}}& a^{\mathrm{II}}\end{array}\right]\left[\begin{array}{c}{x}_5^R\\ x_5^I\\ x_6^R\\ x_6^I\end{array}\right]+{\left[{\left(H_e^{\mathrm{II}}\right)}^T{n}_{\mathrm{equ}}^{\mathrm{II}}\right]}_{\mathrm{last}4\mathrm{rows}}---\left(26\right)$

When channel conversion is slow, can thinks that twice retransfer channel coefficient is constant, can find, according to | I ⁱ+ I ^iI| minimum criteria, the distracter that the retransmission frame optimum code matrix that search obtains is corresponding is just the opposite number of transmission disturbance item first, i.e. I ^iI=-I ⁱ, then the merging equivalent channel correlation matrix flowing 1 is:

$H_{c,\mathrm{stream}1}^{I+\mathrm{II}}=\left[\begin{array}{cccc}{a}^I+a^{\mathrm{II}}& 0& 0& 0\\ 0& a^I+a^{\mathrm{II}}& 0& 0\\ 0& 0& a^I+a^{\mathrm{II}}& 0\\ 0& 0& 0& a^I+a^{\mathrm{II}}\end{array}\right]---\left(27\right)$

Thus achieve same complex symbol inside real, imaginary part is completely orthogonal, reduces decoding complexity.

The embodiment of the present application also discloses a kind of adaptive retransmission device of data.

See Fig. 4, it is the data adaptive retransmission arrangement schematic diagram that the application provides.In the diagram, the adaptive retransmission device schematic diagram with multiple relaying is indicated.

Described device comprises:

Data receiver 1, for when carrying out decoding generation decoding error to the data received, sends repeat requests to base station;

Base station 3, after receiving described repeat requests, retransmits Criterion of Selecting according to optimum and chooses optimum re-transmission encoder matrix, data retransmission, new biography data and optimum preconditioning matrix numbering is sent to relaying in space-time coding matrices set.

Relaying 2, for the data retransmission sent base station in a distributed fashion and new biography data loading being entered optimum re-transmission encoder matrix, and is forwarded to described data receiver.

See Fig. 5, it is the embodiment of the present application base station schematic diagram.

Present invention also provides a kind of base station.

Described base station comprises:

Repeat requests acquisition module 31, for obtaining the repeat requests that data receiver sends to described base station;

Data retransmission sending module 32, after receiving described repeat requests, in space-time coding matrices set, retransmit Criterion of Selecting according to optimum choose optimum re-transmission encoder matrix, data retransmission, new biography data and optimum preconditioning matrix numbering is sent to each relaying.

Preferably, described base station comprises further:

Encoder matrix set acquisition module, for the quantity according to relaying, choose a line number and equal the MDC-QO-STBC encoder matrix of the quantity of described relaying as basic coding matrix, the line order of described basic coding matrix is converted, obtains space-time coding matrices set.

Preferably, described base station comprises further:

First pretreatment module, for carrying out preliminary treatment to sending signal first, obtaining the transmission signal of reality, imaginary part restructuring, sending pretreated signal to each relaying.

Preferably, described first pretreatment module is specially:

Described first pretreatment module be used for by real, the imaginary component of described transmission signal from and order arrangement, be multiplied by a preconditioning matrix, obtain the transmission signal of reality, imaginary part restructuring, the numbering of described transmission signal and optimum preconditioning matrix is sent to each relaying with signalling format; The numbering of described preconditioning matrix is identical with the numbering of described relaying.

The embodiment of the present application also discloses a kind of relaying, and described relaying comprises:

Forwarding module, for receiving data retransmission, new biography data and the optimum preconditioning matrix numbering that base station sends, and the data retransmission sent described base station in a distributed fashion and new biography data loading enter optimum re-transmission encoder matrix, are forwarded to described data receiver.

Preferably, described relaying comprises further:

First Linear processing module, sends signal first for receiving from base station, and chooses from preconditioning matrix group according to preconditioning matrix numbering and number corresponding preconditioning matrix with relaying and carry out linear process to the received signal.

Preferably, described relaying comprises:

Second Linear processing module, for choosing the preconditioning matrix of the optimum preconditioning matrix numbering correspondence that same base station sends from coefficient matrix set, carries out linear process to the re-transmitted signal received.

The embodiment of the present application also discloses a kind of data receiver UE, and described data receiver UE comprises:

Repeat request module, for when carrying out decoding generation decoding error to the data received, sends repeat requests to base station.

Preferably, described receiving terminal UE comprises further:

Symbol level merges module, for the data retransmission of acquisition is carried out symbol level merging with the corresponding data transmitted first.

Linearity test module, for adopting linear detection algorithm to the data retransmission carried out after symbol level merging, obtains the data retransferred.

Maximum Likelihood Detection module, for the single complex symbol Maximum Likelihood Detection of the new biography data acquisition received, obtains new biography data.

The application can describe in the general context of computer executable instructions, such as program module.Usually, program module comprises the routine, program, object, assembly, data structure etc. that perform particular task or realize particular abstract data type.Also can put into practice the application in a distributed computing environment, in these distributed computing environment (DCE), be executed the task by the remote processing devices be connected by communication network.In a distributed computing environment, program module can be arranged in the local and remote computer-readable storage medium comprising memory device.

The above is only the embodiment of the application; it should be pointed out that for those skilled in the art, under the prerequisite not departing from the application's principle; can also make some improvements and modifications, these improvements and modifications also should be considered as the protection range of the application.

Claims (17)

1. an adaptive retransmit method for data, is characterized in that, described method comprises:

Data receiver carries out decoding to the data received, if there is decoding error, described data receiver sends repeat requests to base station;

After described base station receives described repeat requests, in space-time coding matrices set, retransmit Criterion of Selecting according to optimum choose optimum re-transmission encoder matrix, data retransmission, new biography data and optimum preconditioning matrix numbering is sent to each relaying, the data retransmission sent described base station in a distributed fashion by each relaying and new biography data loading enter optimum re-transmission in encoder matrix, are forwarded to described data receiver;

Wherein, described optimum re-transmission Criterion of Selecting is specially:

From described space-time coding matrices set, the encoder matrix choosing the absolute value that meets distracter corresponding to the described encoder matrix distracter sum corresponding with encoder matrix when transmitting first minimum retransmits encoder matrix as optimum;

The described data retransmission that sent described base station in a distributed fashion by each relaying and new biography data loading enter optimum re-transmission in encoder matrix, are forwarded to described data receiver and specifically comprise:

Each relaying is chosen preconditioning matrix by optimum preconditioning matrix numbering and is carried out linear process to the re-transmitted signal received from coefficient matrix set, obtains the re-transmitted signal after processing; Described re-transmitted signal is made up of data retransmission and new biography data;

Re-transmitted signal after described process is loaded into the optimum encoder matrix that retransmits and is sent to data receiver by each relaying, and the re-transmitted signal after the described process that described each relaying sends forms distributed space time block coding DSTBC matrix.

2. method according to claim 1, is characterized in that, described space-time coding matrices set is obtained by following steps:

According to the quantity of relaying, choose a line number and equal the minimum decoding complexity space-time block code MDC-QO-STBC matrix of the quantity of described relaying as basic coding matrix;

The line order of described basic coding matrix is converted, obtains space-time coding matrices set.

3. method according to claim 2, is characterized in that, described space-time coding matrices set is:

The line order of described basic coding matrix is converted in the space-time coding matrices obtained, there is the set of the space-time coding matrices composition of disturbance item absolute value.

4. method according to claim 1, it is characterized in that, described each relaying in a distributed fashion by base station the data retransmission sent out and new biography data be loaded into simultaneously and optimumly retransmit encoder matrix, and after being forwarded to described data receiver, described method comprises further:

After described data receiver receives re-transmitted signal, carry out decoding and obtain described data retransmission and new biography data.

5. method according to claim 4, is characterized in that, after described data receiver receives re-transmitted signal, carries out decoding and obtains described data retransmission and new biography data specifically comprise:

The described data retransmission received is carried out symbol level merging with the corresponding data transmitted first by described data receiver, adopts linear detection algorithm, obtains the data retransferred;

Described data receiver, to the single complex symbol maximum likelihood algorithm of the new biography data acquisition received, obtains described new biography data.

6. method according to claim 1, is characterized in that, the data that described data receiver receives are obtained by following steps:

Preliminary treatment is carried out to sending signal first in described base station, sends pretreated signal to each relaying;

Described each relaying carries out linear process respectively to the received signal, and then each relaying is simultaneously to the signal after described data receiver transmission processing, and the signal after described process forms distributed space time block coding DSTBC matrix.

7. require the method described in 6 according to claim, it is characterized in that, described transmission signal is map to standard planisphere gained after the decoding of information bit channel.

8. method according to claim 7, is characterized in that, preliminary treatment is carried out to sending signal first in described base station, sends pretreated signal specifically comprise to each relaying:

Described base station by real, the imaginary component of described transmission signal from and order arrangement;

Be multiplied by a preconditioning matrix, obtain the transmission signal of reality, imaginary part restructuring, the numbering of described transmission signal and preconditioning matrix is sent to each relaying with signalling format; The numbering of described preconditioning matrix is identical with the numbering of described relaying;

Described each relaying carries out linear process respectively to the received signal and specifically comprises:

Send signal described in described relay reception, and choose from preconditioning matrix group according to the numbering of described preconditioning matrix and number corresponding preconditioning matrix with relaying and carry out linear process to the received signal.

9. a base station, is characterized in that, described base station comprises:

Repeat requests acquisition module, for obtaining the repeat requests that data receiver sends to described base station;

Data retransmission sending module, choosing optimum re-transmission encoder matrix for retransmitting Criterion of Selecting according to optimum in space-time coding matrices set, data retransmission, new biography data and optimum preconditioning matrix being edited and released and delivering to each relaying; Wherein, described optimum retransmits Criterion of Selecting and is specially: from described space-time coding matrices set, and the encoder matrix choosing the absolute value that meets distracter corresponding to the described encoder matrix distracter sum corresponding with encoder matrix when transmitting first minimum retransmits encoder matrix as optimum.

10. base station according to claim 9, is characterized in that, described base station comprises further:

Encoder matrix set acquisition module, for the quantity according to relaying, choose a line number and equal the MDC-QO-STBC encoder matrix of the quantity of described relaying as basic coding matrix, the line order of described basic coding matrix is converted, obtains space-time coding matrices set.

11. base stations according to claim 9, is characterized in that, described base station comprises further:

First pretreatment module, for carrying out preliminary treatment to sending signal first, obtaining the transmission signal of reality, imaginary part restructuring, and sending pretreated signal to each relaying.

12. base stations according to claim 11, is characterized in that, described first pretreatment module is specially:

Described first pretreatment module be used for by real, the imaginary component of described transmission signal from and order arrangement, be multiplied by a preconditioning matrix, obtain the transmission signal of reality, imaginary part restructuring, the numbering of described transmission signal and preconditioning matrix is sent to each relaying with signalling format; The numbering of described preconditioning matrix is identical with the numbering of described relaying.

13. 1 kinds of relayings, is characterized in that, described relaying comprises:

Forwarding module, for receiving data retransmission, new biography data and the optimum preconditioning matrix numbering that base station sends, and the data retransmission sent described base station in a distributed fashion and new biography data loading enter optimum re-transmission encoder matrix, are forwarded to described data receiver; Wherein, the described data retransmission that sent described base station in a distributed fashion and new biography data loading enter optimumly to retransmit in encoder matrix, be forwarded to described data receiver specifically to comprise: each relaying is chosen preconditioning matrix by optimum preconditioning matrix numbering and carried out linear process to the re-transmitted signal received from coefficient matrix set, obtains the re-transmitted signal after processing; Described re-transmitted signal is made up of data retransmission and new biography data; Re-transmitted signal after described process is loaded into the optimum encoder matrix that retransmits and is sent to data receiver by each relaying, and the re-transmitted signal after the described process that described each relaying sends forms distributed space time block coding DSTBC matrix.

14. relayings according to claim 13, is characterized in that, described relaying also comprises:

First Linear processing module, sends signal first for receiving from base station, and chooses from preconditioning matrix group according to preconditioning matrix numbering and number corresponding preconditioning matrix with relaying and carry out linear process to the received signal.

15. relayings according to claim 13, is characterized in that, described relaying comprises:

Second Linear processing module, carries out linear process for choosing preconditioning matrix by optimum pre-coding matrix numbering from coefficient matrix set to the re-transmitted signal received.

16. 1 kinds of data receiver UE, is characterized in that, described receiving terminal UE comprises:

Repeat request module, for when carrying out decoding generation decoding error to the data received, sends repeat requests to base station;

Symbol level merges module, for the data retransmission of reception is carried out symbol level merging with the corresponding data transmitted first;

Linearity test module, for adopting linear detection algorithm to the data retransmission carried out after symbol level merging, obtains the data retransferred;

Maximum Likelihood Detection module, for the single complex symbol Maximum Likelihood Detection of the new biography data acquisition received, obtains new biography data.

The adaptive retransmission device of 17. 1 kinds of data, described device comprises:

Data receiver, for when carrying out decoding generation decoding error to the data received, sends repeat requests to base station;

Base station, after receiving described repeat requests, retransmits Criterion of Selecting according to optimum and chooses optimum re-transmission encoder matrix, data retransmission, new biography data and optimum preconditioning matrix numbering is sent to relaying in space-time coding matrices set; Wherein, described optimum retransmits Criterion of Selecting and is specially: from described space-time coding matrices set, and the encoder matrix choosing the absolute value that meets distracter corresponding to the described encoder matrix distracter sum corresponding with encoder matrix when transmitting first minimum retransmits encoder matrix as optimum;

Relaying, for the data retransmission sent base station in a distributed fashion and new biography data loading being entered optimum re-transmission encoder matrix, is forwarded to described data receiver;

Wherein, described relaying specifically for: from coefficient matrix set, choose preconditioning matrix by optimum preconditioning matrix numbering linear process carried out to the re-transmitted signal received, obtain the re-transmitted signal after processing; Described re-transmitted signal is made up of data retransmission and new biography data; And the re-transmitted signal after described process is loaded into the optimum encoder matrix that retransmits and is sent to data receiver, the re-transmitted signal after the described process that described each relaying sends forms distributed space time block coding DSTBC matrix.