CN100358260C - Multiple code receiver of multiple input and multiple output under broad band channel - Google Patents

Abstract

The present invention discloses a multi-code receiver of a multi-input multi-output system (MIMO) under a wideband channel, which comprises a de-spread unit group used for demodulating and spreading the vector of a received signal to obtain the vector of a de-spread signal, wherein the de-spread unit group sends the vector of the de-spread signal to a first-stage joint detection structure; the data flow interference of other code channels, the other data flow interference of the code channel and the interference of symbols of the data flow are eliminated in the code domain parallel interference cancellation of the first-stage joint detection structure; a final-stage joint detection structure carries out final-stage joint detection for the vector of the corrected de-spread signals of all data flow of all the code channels of an upper stage joint detection structure to obtain the estimation values of all data flow symbols. After the present invention is applied, the demodulating problem of multi-code repeated use under a frequency-selectivity channel in an MIMO system is effectively solved; the processing time delay is greatly reduced. The calculation amounts and the realizing complexity are reduced.

Description

Many yards receivers of multi-input multi-output system under a kind of broad-band channel

Technical field

The present invention relates to wireless communication technology field, many yards receivers of multiple-input and multiple-output (MIMO) system under particularly a kind of broad-band channel.

Background technology

The MIMO technology is the major technological breakthrough of wireless communication field, and it can improve the capability of communication system and the availability of frequency spectrum exponentially under the situation that does not increase bandwidth.The MIMO technology adopts many antennas to send simultaneously and received signal at transmitting terminal and receiving terminal.Because the signal that each transmitting antenna sends simultaneously takies same frequency band, thereby communication bandwidth does not increase.There is a space channel between each transmitting antenna and each reception antenna.If the channel impulse response of each space channel is independent, then mimo system can be created a plurality of parallel independently space channels by a plurality of transmitting antennas and a plurality of reception antenna between transmitting terminal and receiving terminal.Transmit information independently by these parallel space channels, the transmission data rate of mimo system is multiplied.

There are D-BLAST (Diagonal Bell Laboratories Layered Space-timeArchitecture) method and V-BLAST (Vertical Bell Laboratories Layered Space-timeArchitecture) method can realize the demodulation of mimo system at present respectively.But the complexity of D-BLAST method is very high, is not easy real-time implementation, and the V-BLAST method only is applicable to the demodulation of mimo system under the narrow band channel, and can't realize the demodulation of mimo system under the broad-band channel.The V-BLAST method is the successive interference cancellation method in spatial domain under the solid size, and can't eliminate the mutual interference mutually between the code channel and code channel under the many yards transmissions.

Also have CD-SIC V-BLAST method and respective receiver can realize the demodulation of mimo system in the prior art.Fig. 1 is the structural representation of CD-SIC V-BLAST receiver.As shown in Figure 1, code channel k ₀N correlator bank device channel code k ₀Received signal to N root reception antenna is carried out despreading, obtains code channel k ₀The despread signal of following N root antenna.The V-BLAST detector is to code channel k ₀The despread signal of following N root antenna detects and serial spatial domain interference cancellation, obtains code channel k ₀The estimation of following N root antenna transmission symbolic vector

, then in the CD-SIC device the code channel k that has detected ₀Signal from received signal, eliminate the received signal vector that obtains revising Then carry out the demodulation of N root antenna transmission symbolic vector under the next code channel.

Yet CD-SIC V-BLAST method only is applicable to narrow band channel, and can't be applied in the frequency selective channel.Simultaneously, in CD-SIC V-BLAST method, adopt quantizer Q () that input signal is carried out hard decision, and the performance of hard decision is unsatisfactory; And the serial of each symbol detects and makes processing delay very big in successive interference cancellation between the code channel and the sign indicating number.

Summary of the invention

In view of this, main purpose of the present invention is many yards receivers that propose mimo system under a kind of broad-band channel, to realize the demodulation of many yards multiplexing mimo systems under the frequency-selective channel.

For achieving the above object, technical scheme of the present invention is achieved in that

Many yards receivers of multi-input multi-output system under a kind of broad-band channel, described many yards receivers comprise:

The despread unit group is used for to received signal that vector carries out despreading, obtains the despread signal vector, and sends described despread signal vector to first order joint-detection structure;

First order joint-detection structure, the despread signal vector is carried out sign estimation, the signal that obtains all data flow under each code channel is estimated to estimate with the resultant signal of each code channel, estimate and the resultant signal of each code channel is estimated and the received signal vector carries out a yard territory parallel interference cancellation by the signal of all data flow of all code channels, obtain the despread signal vector of the correction of each each data flow of code channel, and send the despread signal vector of correction of all data flow of all code channels to next stage joint-detection structure, wherein in the parallel interference cancellation of described sign indicating number territory, eliminate the interference of the data flow of other code channel, interference between the symbol of the interference of other data flow of this code channel and notebook data stream;

Afterbody joint-detection structure is carried out the afterbody joint-detection to the despread signal vector from the correction of all data flow of all code channels of upper level joint-detection structure, obtains the sign estimation value of all data flow of all code channels.

Described many yards receivers further comprise the intergrade joint-detection structure that is no less than one-level, each intergrade joint-detection structure is connected in series, wherein each intergrade joint-detection structure is carried out sign estimation respectively to the despread signal vector from the correction of each data flow of each code channel of upper level joint-detection structure, the signal that obtains each each data flow of code channel is estimated to estimate with the resultant signal of each code channel, and estimate and the resultant signal of each code channel is estimated and the received signal vector carries out intergrade sign indicating number territory interference cancellation by the signal of all data flow of all code channels, obtain the despread signal vector of correction of the further renewal of each each data flow of code channel, and send the despread signal vector of correction of further renewal of all data flow of all code channels to next stage joint-detection structure, wherein in the parallel interference cancellation of described sign indicating number territory, eliminate the interference of the data flow of other code channel, interference between the symbol of the interference of other data flow of this code channel and notebook data stream.

Described first order joint-detection structure comprises:

C first order detecting unit, wherein C is a code channel number, each first order detecting unit is used for being obtained estimating with the signal of all data flow of the corresponding code channel of despread signal vector and resultant signal is estimated by the despread signal vector, and sends the signal estimation and the resultant signal estimation of all data flow of described and the corresponding code channel of despread signal vector to first order sign indicating number territory interference cancellation and despread signal vector amending unit;

First order sign indicating number territory interference cancellation and despread signal vector amending unit, be used for the signal of all data flow of described and the corresponding code channel of despread signal vector is estimated and total signal estimation and received signal vector carries out the chip-level interference cancellation, obtain the despread signal vector of all corrections of each code channel.

Described afterbody joint-detection structure comprises C afterbody detecting unit, wherein C is a code channel number, each afterbody detecting unit is corresponding to a code channel, each afterbody detecting unit all is used for the despread signal vector of the correction of all data flow of the code channel corresponding with this afterbody detecting unit of upper level joint-detection structure transmission is carried out sign estimation, obtains the sign estimation of all data flow of the code channel corresponding with this afterbody detecting unit.

Described each intergrade joint-detection structure comprises:

C intergrade detecting unit, wherein C is a code channel number, each intergrade detecting unit is used for the despread signal vector of the correction of all data flow of the code channel corresponding with this intergrade detecting unit is detected, the signal that obtains all symbols of this code channel estimates and resultant signal is estimated, and sends the signal estimation and the resultant signal estimation of all symbols of described this code channel to intergrade sign indicating number territory interference cancellation and despread signal vector amending unit;

Intergrade sign indicating number territory interference cancellation and despread signal vector amending unit, estimate and resultant signal estimation and received signal vector are finished the chip-level interference cancellation according to the signal of all symbols of all code channels, and obtain the despread signal vector of all corrections of each code channel, and send the despread signal vector of all corrections of described each code channel to next stage joint-detection structure.

Described first order detecting unit comprises:

The forward direction filtering of despread signal vector to input is finished by the forward direction filtering matrix of input in multiple-input and multiple-output feedforward filter MIMO FFF unit, and gives adder with the signal phasor that filtering obtains;

Adder be used to obtain signal phasor poor of the signal phasor of MIMO FFF unit output and the output of multiple-input and multiple-output feedback filter MIMO FBF unit, and the difference that will obtain is given soft judge unit;

Soft judge unit, each component that is used for difference that adder is sended over carries out soft-decision, obtains the sign estimation of each data flow, and gives signal estimation unit and MIMOFBF unit with the sign estimation of all data flow;

The weight matrix computing unit is used for being finished by the despread signal vector of input the calculating of forward direction filtering weight matrix and feedback filtering weight matrix, and gives MIMO FFF the unit with the forward direction filtering matrix, gives MIMO FBF the unit with the feedback filtering matrix;

The feedback filtering of the vector that the sign estimation of M data flow of soft judge unit input is formed is finished by the feedback filtering matrix in MIMO FBF unit, and gives adder with the signal phasor that filtering obtains;

The signal estimation unit, be used for obtaining the signal estimation of each data flow and the resultant signal estimation of all data flow, and the signal estimated result of each data flow and the resultant signal of all data flow are estimated to give first order sign indicating number territory interference cancellation and despread signal vector amending unit according to the sign estimation of all data flow.

Described afterbody detecting unit comprises M afterbody sign estimation unit, wherein M is a number of transmit antennas, each sign estimation unit is corresponding to a symbol, each sign estimation unit is used for the despread signal vector of the correction of respective stream of data is carried out sign estimation, obtains the sign estimation value of this data flow.

Described intergrade detecting unit comprises:

M intergrade sign estimation unit, wherein M is the number of transmitting antenna, the despread signal vector of correction that described M intergrade sign estimation unit is used for M data flow of corresponding code channel that upper level joint-detection structure is sended over carries out sign estimation, and sends the sign estimation value of M data flow to intergrade signal estimation unit;

Intergrade signal estimation unit, the signal that is used to finish the sign estimation of a described M data flow estimates and resultant signal is estimated, and sends the signal estimation and the resultant signal estimation of a described M data flow to next stage joint-detection structure.

From above technical scheme as can be seen, many yards receivers of mimo system efficiently solve the demodulation problem of many yards multiplexing mimo systems under the frequency-selective channel under the broad-band channel of the present invention, and adopted the parallel interference cancellation reception, obtain bigger performance by less progression and improved, thereby greatly reduced processing delay.Simultaneously, in first order sign indicating number territory parallel interference cancellation and intergrade sign indicating number territory parallel interference cancellation, not only eliminate the interference of data flow of other code channel and the interference of other data flow of this code channel, also eliminated the interference between the symbol of notebook data stream.This processing mode has not only improved the performance of every grade of sign indicating number territory parallel interference cancellation, and when next stage sign indicating number territory parallel interference cancellation is handled, the detection of each data flow detection method according to flat fading channel is detected, thus greatly simplified subsequent stages joint-detection structure internal structure, reduced amount of calculation, reduced implementation complexity.And many yards receivers of the present invention adopt soft decision method to improve the performance of sign estimation, have solved the lower problem of hard decision performance of symbol in the existing method, thereby have improved the sign estimation performance of data flow significantly.

Simultaneously, in intergrade joint-detection structure and afterbody joint-detection structure, obtain sending the estimation of symbol behind application the present invention, and the amount of calculation of sign estimation unit and complexity have obtained greatly to reduce with the sign estimation unit.

Description of drawings

Fig. 1 is the structural representation of CD-SIC V-BLAST receiver.

Fig. 2 is the structural representation of many yards receivers of mimo system under the broad-band channel of one embodiment of the invention.

Fig. 3 is the structural representation of the despread unit group of many yards receivers of mimo system under the broad-band channel of one embodiment of the invention.

Fig. 4 is the structural representation of the first order joint-detection structure of many yards receivers of mimo system under the broad-band channel of one embodiment of the invention.

Fig. 5 is the structural representation of the intergrade joint-detection structure of many yards receivers of mimo system under the broad-band channel of an embodiment for the present invention.

Fig. 6 is the structural representation of the afterbody joint-detection structure of many yards receivers of mimo system under the broad-band channel of an embodiment for the present invention.

Fig. 7 is the first order detecting unit structural representation of many yards receivers of mimo system under the broad-band channel of an embodiment for the present invention.

Fig. 8 is the first order sign indicating number territory interference cancellation of many yards receivers of mimo system under the broad-band channel of an embodiment and the structural representation of despread signal vector amending unit for the present invention.

Fig. 9 is the structural representation of the intergrade detecting unit of the intergrade joint-detection structure of many yards receivers of mimo system under the broad-band channel of an embodiment for the present invention.

Figure 10 is the structural representation of the afterbody detecting unit of the afterbody joint-detection structure of many yards receivers of mimo system under the broad-band channel of an embodiment for the present invention.

Embodiment

For making the purpose, technical solutions and advantages of the present invention express clearlyer, the present invention is further described in more detail below in conjunction with drawings and the specific embodiments.

Suppose that M is a number of transmit antennas, adopt N root antenna to receive.The chip-level received signal vector of N dimension is X (t).Transmitting terminal has adopted C ovsf code to carry out the multiplexing transmission of sign indicating number.C ovsf code is respectively: ovsf code c, and c=1,2,3 ..., C.

Fig. 2 is the structural representation of many yards receivers of mimo system under the broad-band channel of one embodiment of the invention.As shown in Figure 2, these many yards receivers are formed (S 〉=2) by a despread unit group 201 and S level PIC structure.S level PIC structure comprises first order joint-detection structure 202, (S-2) individual intergrade joint-detection structure 203 and afterbody joint-detection structure 204.

Despread unit group 201 respectively with C spreading code to received signal vector carry out despreading, obtain C despread signal vector, wherein, c despread signal vector by c spreading code (promptly c channel code and scrambler are long-pending) to received signal in the vector each component carry out despreading and obtain, be the despread signal vector of c code channel.

202 pairs of despread signal vectors from C code channel of despread unit group 201 of first order joint-detection structure carry out first order united detection processing.Comprising: the despread signal vector from C code channel of despread unit group 201 is carried out the multiple-input and multiple-output decision-feedback respectively estimate, obtain the sign estimation of all M data flow under each code channel, and obtain the signal estimation of M data flow under each code channel and the resultant signal estimation of each code channel by the sign estimation of M data flow under each code channel; Then, estimate and the resultant signal of each code channel is estimated and the received signal vector carries out a yard territory parallel interference cancellation and handles, obtain the despread signal vector of the correction of each each data flow of code channel by the signal of all data flow of C code channel.In the process of the despread signal vector of the correction that obtains each each data flow of code channel by sign indicating number territory interference cancellation, not only to eliminate the interference of the data flow of other code channels, and to eliminate the interference of other data flow of this code channel, also to eliminate the interference between the symbol of notebook data stream simultaneously, make the interference that has not only cut other code channel data flow in the despread signal vector of correction of each data flow, and cut the interference of other data flow of this code channel, also cut simultaneously between the symbol of notebook data stream and disturbed.

First intergrade joint-detection structure 203 (being second level joint-detection structure) is carried out second level united detection processing, the despread signal vector of the correction of all data flow of the C that is further a upgraded code channel to the despread signal vector from the correction of all data flow of C code channel of first order joint-detection structure 202.Comprising: the sign estimation of carrying out each each data flow of code channel by despread signal vector respectively from the correction of each data flow of each code channel of first order joint-detection structure 202, obtain the sign estimation value of C all data flow of code channel, sign estimation value by all M of each code channel data flow obtains the signal estimation of each each data flow of code channel and the resultant signal estimation of each code channel, and estimate and the resultant signal of each code channel is estimated and the received signal vector carries out sign indicating number territory parallel interference cancellation processing second time by the signal of all data flow of C code channel, obtain the despread signal vector of correction of the further renewal of each each data flow of code channel.

The processing procedure of remaining intergrade PIC structure 203 is identical successively.So can obtain the processing procedure of all intergrade PIC structures 203 be:

Carrying out i (i=2, S-1) level is during united detection processing, carry out i level united detection processing, the despread signal vector of the correction of all data flow of the C that is further a upgraded code channel by despread signal vector from the correction of all data flow of C the code channel of (i-1) level associating detection architecture.Comprising: the sign estimation of carrying out each each data flow of code channel by the despread signal vector of correction respectively from each data flow of each code channel of (i-1) level united detection processing, obtain the sign estimation value of C all data flow of code channel, sign estimation value by all M of each code channel data flow obtains the signal estimation of each each data flow of code channel and the resultant signal estimation of each code channel, and estimate and the resultant signal of each code channel is estimated and the received signal vector carries out the i time sign indicating number territory parallel interference cancellation processing by the signal of all data flow of C code channel, obtain the despread signal vector of correction of the further renewal of each each data flow of code channel.

204 pairs of despread signal vectors from the correction of all data flow of C code channel of (S-1) level associating detection architecture of afterbody joint-detection structure carry out S level united detection processing, obtain the sign estimation value of each each data flow of code channel, the sign estimation value of this C each digital data stream of code channel is exactly the final testing result of C each data flow of code channel.Comprising: carry out the sign estimation of each each data flow of code channel respectively by the despread signal vector of correction, obtain the sign estimation value of each each data flow of code channel from each data flow of each code channel of (S-1) level united detection processing.

Fig. 3 is the structural representation of the despread unit group of many yards receivers of mimo system under the broad-band channel of one embodiment of the invention.As shown in Figure 3, despread unit group 201 is made up of C despread unit 301, and c despread unit 301 usefulness ovsf code c and scrambler are finished the despreading to each component among the input N dimension baseband receiving signals vector X (t), obtain the despread signal vector that c N ties up.The C that despread unit group 201 obtains despread signal vector sent into first order joint-detection structure 202 concurrently respectively.

Fig. 4 is the structural representation of the first order joint-detection structure of many yards receivers of mimo system under the broad-band channel of one embodiment of the invention.As shown in Figure 4, first order joint-detection structure 202 comprises C first order detecting unit 401 and first order sign indicating number territory interference cancellation and despread signal vector amending unit 402.The C that despread unit group 201 obtains despread signal vector sent into C first order detecting unit 401 in the first order joint-detection structure 202 concurrently respectively.C first order detecting unit 401 obtained the signal of M the data flow of yard c and estimates and total signal estimation by c despread signal vector.The output signal of C first order detecting unit 401 all enters the first order sign indicating number territory interference cancellation and the despread signal vector amending unit 402 of first order joint-detection structure 202.First order sign indicating number territory interference cancellation and despread signal vector amending unit 402 are finished chip-level interference cancellation and despreading signal phasor, at first, 402 inside in the unit, obtain the despread signal vector of C code channel of residual signals by C despread unit, and then obtain the correction of the despread signal vector of all data flow of code channel by despread signal vector amending unit, obtain the despread signal vector of M the despread signal vector of revising of sign indicating number 1 to M the correction of sign indicating number C.The despread signal vector of revising is admitted to second level joint-detection structure 203 as the output signal of first order joint-detection structure 202.

Fig. 5 is the intergrade joint-detection structural representation of broadband receiver of the mimo system of one embodiment of the invention.Second level joint-detection structure to the (S-1) level associating detection architecture all is an intergrade joint-detection structure, and has identical structure.Intergrade joint-detection structure 203 is successively between first order joint-detection structure 202 and S level associating detection architecture 204.As shown in Figure 5, intergrade joint-detection structure 203 comprises C intergrade detecting unit 501 and intergrade sign indicating number territory interference cancellation and despread signal vector amending unit 502.When 1＜i＜S, (i-1) level associating detection architecture walks abreast M the despread signal vector of revising of sign indicating number 1 to M the despread signal vector of revising of sign indicating number C and gives the i level and unite C intergrade detecting unit 501 in the detection architecture.C intergrade detecting unit 501 estimated and the resultant signal estimation by the signal that detection obtains yard all symbols of c by the despread signal vector of the correction of all symbols of sign indicating number c.The output signal of C intergrade detecting unit 501 all enters intergrade sign indicating number territory interference cancellation and despread signal vector amending unit 502.Intergrade sign indicating number territory interference cancellation and despread signal vector amending unit 502 are finished the chip-level interference cancellation by full-scale input, and obtain M the despread signal vector revised of 1 M despread signal vector of revising of sign indicating number, and M the despread signal vector of revising of sign indicating number 1 to the despread signal vector of M the correction of sign indicating number C walked abreast send into (i+1) and grade unite detection architecture to sign indicating number C.

According to above-mentioned processing procedure, finish the signal processing of second level joint-detection structure to the (S-1) joint-detection structure successively.

Fig. 6 is the structural representation of the afterbody joint-detection structure of many yards receivers of mimo system under the broad-band channel of one embodiment of the invention.As shown in Figure 6, afterbody joint-detection structure 204 comprises C afterbody detecting unit 601.C afterbody detecting unit 601 obtains the sign estimation of M the data flow of yard c by the despread signal vector of M the correction of the sign indicating number c of (S-1) level associating detection architecture 203, and the sign estimation of M data flow is exactly the final detection result of M data flow under yard c.

Introduce among Fig. 2 among despread unit group 201, Fig. 4 among first order sign indicating number territory interference cancellation and despread signal vector amending unit 402 among first order detecting unit 401, Fig. 4, Fig. 5 afterbody detecting unit 601 in the intergrade detecting unit 501 and Fig. 6 below in detail.

If ovsf code c is o _c(t), scrambler is s (t).Chip-level received signal vector X (t)=[X that is input as the N dimension of c despread unit 301 in the despread unit group 201 ₁(t), X ₂(t) ..., X _N(t)] ^T, the output x of this despread unit then _c(k)=[x _C1(k), x _C2(k) ..., x _CN(k)] ^TCalculate according to following formula:

$x_{\mathrm{on}}\left(t\right)=\frac{1}{T_s}\underset{T_s}{\∫}{X}_n\left(t\right)o_c\left(t\right)s^{*}\left(t\right),n=\mathrm{1,2},...,N,c=\mathrm{1,2},...,C---\left(1\right)$

Wherein, T _sThe is-symbol cycle.

The signal model of mimo system:

x _c(k) be to obtain, can be write as following form with long-pending vector X (t) despreading to received signal of ovsf code c and scrambler:

$x_c\left[k\right]=\underset{m=1}{\overset{M}{\mathrm{\Σ}}}{H}_{c,m}{s}_{c,m}\left[k\right]+n_c\left(k\right)---\left(2\right)$

Here

s _{C, m}[k]=[s _{C, m}[k+L _a] ... s _{C, m}[k-L _c]] ^T, s _{C, m}[k] is k symbol of m root antenna transmission;

$H_{c,m}=\left[\begin{array}{ccc}{h}_{c,1,m}(-L_a)& ...& h_{c,1,m}\left(L_c\right)\\ .& .& .\\ .& .& .\\ .& .& .\\ h_{c,N,m}(-L_a)& ...& h_{c,N,m}\left(L_c\right)\end{array}\right],$ Be a N * L rank matrix, its n line display transmitting antenna m and the channel impulse response sequence between the reception antenna n, L _aAnd L _cBe respectively the non-causal memory and the cause and effect memory of channel, and L=L _a+ L _c+ 1;

n _c[k]=[n _{C, 1}[k] ... n _{C, N}[k]] ^T, be a N dimension noise vector, and its each component obedience N (0, σ _n ²) distribute, and I _NIt is the unit matrix on N rank.

The following describes the first order detecting unit 401 in the first order joint-detection structure 202.

Fig. 7 is the first order detecting unit structural representation of many yards receivers of mimo system under the broad-band channel of one embodiment of the invention.As shown in Figure 7, the first order detecting unit 401 of first order PIC structure 202 is made of a MIMO-DFE demodulating unit 701 and a signal estimation unit 702.

MIMO-DFE demodulating unit 701 is made of weight matrix computing unit 703, MIMO FFF unit 704, MIMO FBF unit 705, adder unit 706 and soft judge unit 707.Wherein, weight matrix computing unit 703 is finished the calculating of forward direction filtering weight matrix and feedback filtering weight matrix by the despread signal vector of input, and gives MIMO FFF unit 704 with the forward direction filtering matrix, gives MIMO FBF unit 705 with the feedback filtering matrix; Forward direction filtering to the despread signal vector is finished by the forward direction filtering matrix of input in MIMO FFF unit 704, and gives adder 706 with the signal phasor that filtering obtains; The feedback filtering of the vector that the sign estimation of M data flow of soft judge unit 707 input is formed is finished by the feedback filtering matrix in MIMO FBF unit 705, and gives adder 706 with the signal phasor that filtering obtains; Adder 706 is obtained signal phasor poor of the signal phasor of MIMO FFF unit 704 output and 705 outputs of MIMO FBF unit, and the difference that will obtain is given soft judge unit 707; Each component of the difference that 707 pairs of adders 706 of soft judge unit are brought carries out soft-decision, obtains the sign estimation of each data flow, and gives signal estimation unit 702 and MIMO FBF unit 705 with the sign estimation of M data flow.

Signal estimation unit 702 obtains the signal estimation of each data flow and the resultant signal estimation of all data flow by the sign estimation of M data flow, and the signal estimated result of each data flow and the resultant signal of all data flow are estimated to give the first order interference cancellation and the despread signal vector amending unit 302 of first order joint-detection structure 202.

The signal processing of c first order detecting unit 401 is elaborated as follows:

If the input signal vector of MIMO-DFE demodulating unit 701 is:

${\stackrel{\‾}{x}}_c\left[k\right]=\underset{m=1}{\overset{M}{\mathrm{\Σ}}}{\stackrel{\‾}{H}}_{c,m}{\stackrel{\‾}{s}}_{c,m}\left[k\right]+{\stackrel{\‾}{n}}_c\left(k\right)---\left(3\right)$

Wherein,

${\stackrel{\‾}{x}}_c\left[k\right]=\mathrm{vec}\left[x_c\right[k]...x_c[k-K_f\left]\right],$ K _fBe forward-direction filter length,

$\mathrm{vec}[A_1...A_L]={[A_1^T...A_L^T]}^T;$

${\stackrel{\‾}{s}}_{c,m}\left[k\right]=\left[s_{c,m}\right[k+L_a]...s_{c,m}[k-L_c-K_f]{]}^T;$

${\stackrel{\‾}{H}}_{c,m}=\left[\begin{array}{ccc}{H}_{c,m}& ...& 0\\ .& .& .\\ .& .& .\\ .& .& .\\ 0& ...& H_{c,m}\end{array}\right],$ Be a N (K _f+ 1) * (k+K _f) the Toeplitz matrix on rank;

${\stackrel{\‾}{n}}_c\left[k\right]=\mathrm{vec}\left[n_c\right[k]...n_c[k-K_f\left]\right]$

The weight matrix of MIMO FFF unit 704 is W _c, be N (K _f+ 1) * and M rank matrix, the weight matrix of MIMO FBF unit 705 is V _c, be K _bM * M rank matrix.

MIMO-DFE demodulating unit 701 is finished following 5 functions:

(1) weight matrix computing unit 703 calculates weight matrix W according to following formula _cAnd V _c:

$W_c=R_c^{-1}{\stackrel{\‾}{H}}_{1,c,\mathrm{pres}}---(4a-1)$

$V_c={\stackrel{\‾}{H}}_{1,c,\mathrm{fb}}^H{W}_c---(4a-2)$

Wherein,

$R_c=\underset{m=1}{\overset{M}{\mathrm{\Σ}}}({\stackrel{\‾}{H}}_{1,c,m}{\stackrel{\‾}{H}}_{1,c,m}^H-{\stackrel{\‾}{H}}_{1,c,m,\mathrm{fb}}{\stackrel{\‾}{H}}_{1,c,m,\mathrm{fb}}^H)+{\mathrm{\σ}}^2{I}_{N(K_f+1)\×N(K_f+1)};$

${\stackrel{\‾}{H}}_{1,c,\mathrm{pres}}=[{\stackrel{\‾}{H}}_{1,c,1,\mathrm{pres}}...{\stackrel{\‾}{H}}_{1,c,M,\mathrm{pres}}],$

Representing matrix

L _a+ 1+d _iRow;

${\stackrel{\‾}{H}}_{1,c,\mathrm{fb}}=[{\stackrel{\‾}{H}}_{1,c,1,\mathrm{fb}}...{\stackrel{\‾}{H}}_{1,c,M,\mathrm{fb}}],$ Representing matrix

L _a+ 2+d _iBe listed as L _a+ 1+d _i+ K _fThe matrix that row constitute;

H _{1, c, m}Be H _{C, m}Estimation, by the first time channel estimating obtain; If channel estimating ideal, then H _{1, c, m}=H _{C, m} Be

Estimation.

(2) MIMO FFF unit 704 is by forward direction filtering matrix W _cFinish the input signal vector Filtering, and with filtering y as a result _c[k] gives adder 706:

$y_c\left[k\right]=W_c^H{\stackrel{\‾}{x}}_c\left[k\right]---\left(4b\right)$

(3) MIMO FBF unit 705 is by the feedback filtering matrix V _cFinish filtering to input vector, and with filtering Δ y as a result _c[k] gives adder 706:

$\mathrm{\Δ}{y}_c\left[k\right]=V_c^H{\hat{S}}_{c,\mathrm{fb}}[k-d_i-1]---\left(4c\right)$

Wherein,

s _{C, m}[k] is estimated as

${\hat{S}}_c[k-d_i-1]=\left[{\hat{s}}_{1,c,1}\right[k-d_i-1]...{\hat{s}}_{1,c,M}[k-d_i-1]{]}^T,$ d _iBe the judgement time delay, be nonnegative integer,

${\hat{S}}_{c,\mathrm{fb}}[k-d_i-1]=\mathrm{vec}\left[{\hat{s}}_c\right[k-d_i-1]...{\hat{s}}_c[k-d_i-K_d\left]\right],$ d _iBe feedback filter length;

(4) adder 706 is finished the interference cancellation function:

${\stackrel{\·}{y}}_c\left[k\right]=y_c\left[k\right]-\mathrm{\Δ}{y}_c\left[k\right]---\left(4d\right)$

(5) soft-decision device 707 is finished the input signal vector

The soft-decision of each component, right

M component

Soft-decision as follows:

${\hat{s}}_{1,c,m}\left[k\right]=D\left({\stackrel{\·}{y}}_{c,m}\right),m=\mathrm{1,2},...,M---\left(4e\right)$

Signal estimation unit 702 in the first order detecting unit 401 is finished the signal of each data flow and is estimated and the resultant signal estimation.Every grade of signal estimation unit of uniting in the detection architecture has identical function.

During c code channel detected in i level associating detection architecture, the signal estimation unit was finished following function:

The signal of m data flow is estimated as follows:

$U_{i,c,m}\left[k\right]={\left(H_{i,c,m}\right)}_{L_a+1}{\hat{s}}_{i,c,m}\left[k\right],m=\mathrm{1,2},...,M---\left(4f\right)$

Wherein, H _{I, c, m}Be H _{C, m}In the estimation of i level, that is: (i-1) inferior joint-detection is later on to H _{C, m}Estimation.

Estimate according to formula (4g) and the resultant signal that (4h) obtains M signal flow:

$B_{i,c,m}\left[k\right]=H_{i,c,m}{\hat{P}}_{i,c,m}\left[k\right],m=\mathrm{1,2},...,M---\left(4g\right)$

Wherein, ${\hat{P}}_{i,c,m}\left[k\right]=\left[{\hat{s}}_{i,c,m}\right[k-L_a]...{\hat{s}}_{i,c,m}[k-L_c]{]}^T,$ Be symbol s in the i level PIC structure _{C, m}The estimation of [k].

The resultant signal of M data flow is estimated as follows:

${\hat{x}}_{i,c}\left[k\right]=\underset{m=1}{\overset{M}{\mathrm{\Σ}}}{B}_{i,c,m}\left[k\right]---\left(4h\right)$

Fig. 8 is the first order sign indicating number territory interference cancellation and the despread signal vector amending unit structural representation of many yards receivers of mimo system under the broad-band channel of an embodiment for the present invention.As shown in Figure 8, this unit comprises the amending unit of interference cancellation unit, 801, one sign indicating number territories of C spectrum-spreading unit 802, a C despread unit 803 and a despread signal vector.First order sign indicating number territory interference cancellation and despread signal vector amending unit 402 and intergrade sign indicating number territory interference cancellation and despread signal vector amending unit 502 have identical structure, and finish identical functions.I (i=1,2,, S-1) the sign indicating number territory interference cancellation and the despread signal vector amending unit (being first order sign indicating number territory interference cancellation and despread signal vector amending unit 402 and intergrade sign indicating number territory interference cancellation and despread signal vector amending unit 502) of level associating detection architecture are finished following function:

At first, c spectrum-spreading unit 801 estimated by the resultant signal of c ovsf code, scrambler and c code channel ${\hat{x}}_{i,o}\left(k\right)=[{\hat{x}}_{i,o,1}\left(t\right),{\hat{x}}_{i,o,2}\left(t\right),...,{\hat{x}}_{i,o,N}\left(t\right){]}^T$ Obtain the regenerated signal g of c code channel _{I, o}(t)=[g _{I, o, 1}(t), g _{I, o, 2}(t) ..., g _{I, o, N}(t)] ^T

$g_{i,o,n}\left(t\right)={\hat{x}}_{i,c,n}\left({\mathrm{kT}}_s\right)o_c\left(t\right)s\left(t\right),n=\mathrm{1,2},...,N,c=\mathrm{1,2},...,C---\left(5a\right)$

The regenerated signal of C the code channel that C spectrum-spreading unit 801 obtains is admitted to a yard interference cancellation unit, territory 802.Interference cancellation is finished in sign indicating number interference cancellation unit, territory 802, obtains residual signals.Residual signals is calculated as follows:

$x_{i+1}\left(t\right)=x\left(t\right)-\underset{c=1}{\overset{C}{\mathrm{\Σ}}}{g}_{i,c}---\left(5b\right)$

Residual signals is walked abreast sends into C despread unit 803.C despread unit tieed up residual signals x with c ovsf code and scrambler to the N that imports _I+1(t)=[X _I+1,1(t), X _{I+1,, 2}(t) ..., X _{I+1,, N}(t)] ^TIn each component carry out despreading, obtain despread signal vector x _{I+1, c}(k)=[x _{I+1, c, 1}(k), x _{I+1, c, 2}(k) ..., x _{I+1, c, N}(k)] ^T

$x_{i+1,c,n}\left(t\right)=\frac{1}{T_s}\underset{T_s}{\∫}{X}_{i+1,n}\left(t\right)o_c\left(t\right)s^{*}\left(t\right),n=\mathrm{1,2},...,N,c=\mathrm{1,2},...,C---\left(5c\right)$

Wherein, T _sThe is-symbol cycle.

C the despread signal vector that C despread unit 803 obtains all is admitted to despread signal vector amending unit 804.Despread signal vector amending unit 804 is estimated to obtain the despread signal vector of correction of each data flow of each code channel by the signal of C despread signal vector and sign indicating number all data flow of 1 to sign indicating number C.The despread signal vector of the correction of m data flow of c the code channel that i level associating detection architecture obtains is as follows:

x _i+1，c，m[k]＝x _i+1，c[k]+U _i，c，m[k]，m＝1，2，…，M，c＝1，2，…，C (5d)

The despread signal vector of the correction of all data flow is admitted in (i+1) level associating detection architecture.

Below intergrade detecting unit 501 is described.

Fig. 9 is the intergrade detecting unit structural representation of the intergrade joint-detection structure of many yards receivers of mimo system under the broad-band channel of one embodiment of the invention.As shown in Figure 9, intergrade detecting unit 501 is made of M sign estimation unit 901 and a signal estimation unit 902.M sign estimation unit 901 finished the sign estimation of M data flow respectively.Signal estimation unit 902 is finished the estimation and the resultant signal of each traffic spike and is estimated.In every grade of associating detection architecture, sign estimation unit 901 has identical function.

In c code channel of i (i＞1) level associating detection architecture detected, the input signal of sign estimation unit m was x _{I, c}, [k], following function is finished in this unit:

(1) at first calculates weight vector W _{I, c, m}

Under the ZF criterion, calculate W according to (6a) formula _{I, c, m}, under the MMSE criterion, calculate W according to (6b) formula _{I, c, m}:

$W_{i,c,m}=\frac{F^H}{\left|\right|F\left|\right|},m=\mathrm{1,2},...,M,$ $F={\left(H_{i,c,m}\right)}_{L_a+1}---\left(6a\right)$

$W_{i,c,m}={\mathrm{\σ}}_s^2{F}^H[{\mathrm{\σ}}_s^2{\mathrm{FF}}^H+{\mathrm{\σ}}^2{I}_M{]}^{-1},$ $F={\left(H_{i,c,m}\right)}_{L_a+1}---\left(6b\right)$

(2) counting statistics decision content y _{I, c, m}

y _i，c，m[k]＝W _i，c，mx _i，c，[k]，m＝1，2，…，M(6c)

(3) sign estimation: the soft-decision function is by statistical decision amount y _{I, c}, [k] obtains the estimation of symbol

${\hat{s}}_{i,c,m}\left[k\right]=D\left(y_{i,c,m}\right[k\left]\right),m=\mathrm{1,2},...,M---\left(6d\right)$

Below afterbody detecting unit 601 is described.

Figure 10 is the structural representation of the afterbody detecting unit of the afterbody joint-detection structure of many yards receivers of mimo system under the broad-band channel of an embodiment for the present invention.As shown in figure 10, this unit comprises that M sign estimation unit 1001 constitutes.M sign estimation unit 1001 finished the sign estimation of M data flow respectively.

Sign estimation unit m finishes the function as formula (6a-6d) in c afterbody detecting unit 601.

Parameter value:

K _f, K _bValue can obtain by simulation optimization, also can be according to the requirement that detects performance and complexity is determined;

d ₁Can interval [0, d _MAX] in optimize and to obtain, wherein,

$d_{\mathrm{MAX}}=\left\{\begin{array}{c}{K}_f,(L_c\≥K_d)\\ K_f+L_c-K_b,(L_c\≤K_b)\end{array}\right.---\left(7\right)$

The definition of soft-decision function:

If

y＝a+v

Wherein, a ∈ { A ₁, A ₂..., A _K, { A ₁, A ₂..., A _K) be the set that all possible transmission symbol constitutes; V is a white Gaussian noise.

Then the soft-decision of y=a+v calculates according to following formula:

$\hat{a}=D\left(y\right)=\mathrm{\β}\frac{\underset{k=1}{\overset{K}{\mathrm{\Σ}}}{A}_{k}f\left(y\right|A_k)}{\underset{k=1}{\overset{K}{\mathrm{\Σ}}}f\left(y\right|A_k)}---\left(8a\right)$

Wherein, β is called correction factor, estimates the deviation of the undesirable sign estimation that causes and the deviation of interference cancellation in order to correction channel; F (y|A _k) represent that sending symbol is A _kThe time receive the probability density function of y.β and f (y|A _k) computational methods as follows:

(1) if the symbol that sends is a plural number, then

$f\left(y\right|A_k)=\frac{1}{2\mathrm{\π}{\mathrm{\σ}}^2}{e}^{-\frac{{(\mathrm{YR}-{\mathrm{AR}}_k)}^2+{(\mathrm{YI}-{\mathrm{AI}}_k)}^2}{2{\mathrm{\σ}}^2}}---\left(8b\right)$

Wherein, AR _k, AI _kBe respectively A _kReal part and imaginary part; YR, YI are respectively real part and the imaginary part of y; VR, VI are respectively real part and the imaginary part of v, obey respectively N (0, σ ²) distribute.And β is a plural number.

(2) if sending symbol is real number, then

$f\left(y\right|A_k)=\frac{1}{\sqrt{2\mathrm{\π}}\mathrm{\σ}}{e}^{-\frac{{(\mathrm{YR}-A_k)}^2}{2{\mathrm{\σ}}^2}}---\left(8c\right)$

Wherein, YR is the real part of y; VR is the real part of v, and obedience N (0, σ ²) distribute.And β is a real number.

(3) SNR of the value of β and symbol is closely related, the function of the SNR of is-symbol.

In order to simplify calculating, also can directly make β=1, that is: the influence that the deviation of not considering channel estimating causes sign estimation and interference cancellation.

Usually, to reach certain numerical value at the SNR of receiving terminal symbol (Signal to Noise Ratio), just can make separate the mapping and decoding after bit BLER (Block Error Rate) performance satisfy the requirement of quality of service.For given BLER numerical value, can determine: for BLER performance after making decoding reaches requirement, the required minimum SNR numerical value S that reaches of symbol by emulation _MINAnd get T ₁=S _MIN-δ ₁, T ₂=S _MIN-δ ₂Wherein, δ ₁＞0, δ ₂＞δ ₁

The SNR of if symbol is greater than threshold value T ₁=S _MAX-δ ₁, just think that the channel estimating of this symbol is more accurate, can be similar to and think β=1.

The SNR of if symbol is less than or equal to threshold value T ₂=S _MAX-δ ₂, just think that the SNR of this symbol is too low, make the non-constant of channel estimating, can be similar to and think β=0.

The SNR of if symbol is greater than threshold value T ₂=S _MAX-δ ₂And smaller or equal to threshold value T ₁=S _MAX-δ ₁, can determine by COSSAP emulation or MATLAB simulation optimization: when SNR at (T ₂, T ₁) in the concrete value of β when changing.

δ ₁, δ ₂Value directly influences precision and the SNR optimization interval (T of β to the sign estimation correction for drift ₂, T ₁) size.Can be according to the needs of correction accuracy and computation optimization amount are determined δ ₁And δ ₂Numerical value.

In sum, the β value is as follows:

$\mathrm{\&beta;}=\left\{\begin{array}{c}0,\mathrm{SNR}\&le;{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="C20041005946700241.png,C20041005946700261.png"\; state="\{\{state\}\}">T</figure-callout>}}_2\\ {\mathrm{\&alpha;}}_{i,},{\mathrm{SNR}}_{i-1}<\mathrm{SNR}\&le;\\ 1,\mathrm{SNR}>{\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="C20041005946700241.png"\; state="\{\{state\}\}">T</figure-callout>}}_1\end{array}{\mathrm{SNR}}_i,{\mathrm{SNR}}_i={\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="C20041005946700241.png,C20041005946700261.png"\; state="\{\{state\}\}">T</figure-callout>}}_2+\frac{i(T_1-T_2)}{i},i=\mathrm{1,2},...I\right.---\left(8d\right)$

In the following formula, α _tValue by at less SNR interval [SNR _I-1, SNR _i] COSSAP emulation or MATLAB simulation optimization obtain.Wherein, I optimizes interval (T to SNR ₂, T ₁) quantize the number of the minizone obtain, determine as required.

In above-mentioned MIMO receiver, the span of progression S is 2≤S＜M.Usually, can determine the value of S according to concrete performance and time delay demand.In general, when S=2 or 3, performance is just fine.

The above is preferred embodiment of the present invention only, is not to be used to limit protection scope of the present invention.Within the spirit and principles in the present invention all, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (8)

1, many yards receivers of multi-input multi-output system under a kind of broad-band channel is characterized in that, described many yards receivers comprise:

The despread unit group is used for to received signal that vector carries out despreading, obtains the despread signal vector, and sends described despread signal vector to first order joint-detection structure;

First order joint-detection structure, the despread signal vector is carried out sign estimation, the signal that obtains all data flow under each code channel is estimated to estimate with the resultant signal of each code channel, estimate and the resultant signal of each code channel is estimated and the received signal vector carries out a yard territory parallel interference cancellation by the signal of all data flow of all code channels, obtain the despread signal vector of the correction of each each data flow of code channel, and send the despread signal vector of correction of all data flow of all code channels to next stage joint-detection structure, wherein in the parallel interference cancellation of described sign indicating number territory, eliminate the interference of the data flow of other code channel, interference between the symbol of the interference of other data flow of this code channel and notebook data stream;

Afterbody joint-detection structure is carried out the afterbody joint-detection to the despread signal vector from the correction of all data flow of all code channels of upper level joint-detection structure, obtains the sign estimation value of all data flow of all code channels.

2, many yards receivers of multi-input multi-output system under the broad-band channel according to claim 1, it is characterized in that, described many yards receivers further comprise the intergrade joint-detection structure that is no less than one-level, each intergrade joint-detection structure is connected in series, wherein each intergrade joint-detection structure is carried out sign estimation respectively to the despread signal vector from the correction of each data flow of each code channel of upper level joint-detection structure, the signal that obtains each each data flow of code channel is estimated to estimate with the resultant signal of each code channel, and estimate and the resultant signal of each code channel is estimated and the received signal vector carries out intergrade sign indicating number territory interference cancellation by the signal of all data flow of all code channels, obtain the despread signal vector of correction of the further renewal of each each data flow of code channel, and send the despread signal vector of correction of further renewal of all data flow of all code channels to next stage joint-detection structure, wherein in the parallel interference cancellation of described sign indicating number territory, eliminate the interference of the data flow of other code channel, interference between the symbol of the interference of other data flow of this code channel and notebook data stream.

3, many yards receivers of multi-input multi-output system under the broad-band channel according to claim 1 and 2 is characterized in that, described first order joint-detection structure comprises:

C first order detecting unit, wherein C is a code channel number, each first order detecting unit is used for being obtained estimating with the signal of all data flow of the corresponding code channel of despread signal vector and resultant signal is estimated by the despread signal vector, and sends the signal estimation and the resultant signal estimation of all data flow of described and the corresponding code channel of despread signal vector to first order sign indicating number territory interference cancellation and despread signal vector amending unit;

First order sign indicating number territory interference cancellation and despread signal vector amending unit, be used for the signal of all data flow of described and the corresponding code channel of despread signal vector is estimated and total signal estimation and received signal vector carries out the chip-level interference cancellation, obtain the despread signal vector of all corrections of each code channel.

4, many yards receivers of multi-input multi-output system under the broad-band channel according to claim 1 and 2, it is characterized in that, described afterbody joint-detection structure comprises C afterbody detecting unit, wherein C is a code channel number, each afterbody detecting unit is corresponding to a code channel, each afterbody detecting unit all is used for the despread signal vector of the correction of all data flow of the code channel corresponding with this afterbody detecting unit of upper level joint-detection structure transmission is carried out sign estimation, obtains the sign estimation of all data flow of the code channel corresponding with this afterbody detecting unit.

5, many yards receivers of multi-input multi-output system under the broad-band channel according to claim 2 is characterized in that, described each intergrade joint-detection structure comprises:

C intergrade detecting unit, wherein C is a code channel number, each intergrade detecting unit is used for the despread signal vector of the correction of all data flow of the code channel corresponding with this intergrade detecting unit is detected, the signal that obtains all symbols of this code channel estimates and resultant signal is estimated, and sends the signal estimation and the resultant signal estimation of all symbols of described this code channel to intergrade sign indicating number territory interference cancellation and despread signal vector amending unit;

Intergrade sign indicating number territory interference cancellation and despread signal vector amending unit, estimate and resultant signal estimation and received signal vector are finished the chip-level interference cancellation according to the signal of all symbols of all code channels, and obtain the despread signal vector of all corrections of each code channel, and send the despread signal vector of all corrections of described each code channel to next stage joint-detection structure.

6, many yards receivers of multi-input multi-output system under the broad-band channel according to claim 3 is characterized in that, described first order detecting unit comprises:

The forward direction filtering of despread signal vector to input is finished by the forward direction filtering matrix of input in multiple-input and multiple-output feedforward filter MIMO FFF unit, and gives adder with the signal phasor that filtering obtains;

Adder be used to obtain signal phasor poor of the signal phasor of MIMO FFF unit output and the output of multiple-input and multiple-output feedback filter MIMO FBF unit, and the difference that will obtain is given soft judge unit;

Soft judge unit, each component that is used for difference that adder is sended over carries out soft-decision, obtains the sign estimation of each data flow, and gives signal estimation unit and MIMOFBF unit with the sign estimation of all data flow;

The weight matrix computing unit is used for being finished by the despread signal vector of input the calculating of forward direction filtering weight matrix and feedback filtering weight matrix, and gives MIMO FFF the unit with the forward direction filtering matrix, gives MIMO FBF the unit with the feedback filtering matrix;

The feedback filtering of the vector that the sign estimation of M data flow of soft judge unit input is formed is finished by the feedback filtering matrix in MIMO FBF unit, and gives adder with the signal phasor that filtering obtains;

The signal estimation unit, be used for obtaining the signal estimation of each data flow and the resultant signal estimation of all data flow, and the signal estimated result of each data flow and the resultant signal of all data flow are estimated to give first order sign indicating number territory interference cancellation and despread signal vector amending unit according to the sign estimation of all data flow.

7, many yards receivers of multi-input multi-output system under the broad-band channel according to claim 4, it is characterized in that, described afterbody detecting unit comprises M afterbody sign estimation unit, wherein M is a number of transmit antennas, each sign estimation unit is corresponding to a symbol, each sign estimation unit is used for the despread signal vector of the correction of a symbol of input is carried out sign estimation, obtains the estimated value of this symbol.

8, many yards receivers of multi-input multi-output system under the broad-band channel according to claim 5 is characterized in that, described intergrade detecting unit comprises:

M intergrade sign estimation unit, wherein M is the number of transmitting antenna, the despread signal vector of correction that described M intergrade sign estimation unit is used for M data flow of corresponding code channel that upper level joint-detection structure is sended over carries out sign estimation, and sends the sign estimation value of M data flow to intergrade signal estimation unit;

Intergrade signal estimation unit is used for that signal that estimated value by the symbol of a described M data flow obtains M data flow is estimated and resultant signal is estimated, and sends the signal estimation and the resultant signal estimation of a described M data flow to next stage joint-detection structure.

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