CN101783722A - Transmission method and device for virtual MIMO - Google Patents

Abstract

The invention discloses a sending method for the virtual MIMO. The invention is characterized in that user terminals UE1 and UE2 use the same time-frequency resources and send information according to the same method, wherein the UE1 simultaneously sends DFT pretreatment signal vectors{Xk, Xk+1} at k time and k+1 time to a space-time block grouping encoder for space-time two-dimension encoding treatment in a form of the vector, and outputs two codeword vectors {Xk, Xk+1} at k time and the other two codeword vectors at k+1 time to send the codeword vectors respectively obtained at k time and k+1 time to a first transmitting channel to carry out sub-channel mapping, IFF operation, inserting cyclic prefixes and transmitting treatment; and the codeword vectors respectively obtained at k time and k+1 time are sent to a second channel to carry out sub-channel mapping, IFF operation, inserting cyclic prefixes and transmitting treatment. The invention also discloses a transmitter and a receiver for the virtual MIMO. The invention can fully utilize a multi-antenna system to provide spatial emission diversity gain and improve reliability of link transmission.

Description

A kind of virtual MIMO transmission method and device

Technical field

The present invention relates to the virtual MIMO transmission technology, particularly relate to the transmission method and the device of the virtual MIMO of a kind of DFT-S-OFDM based on space-time block coding.

Background technology

In the LTE wide-band mobile communication system, 3GPP determines that up link adopts the Single Carrier Frequency Division Multiple Access transmission plan based on DFT-S-OFDM, compares with the OFDM transmission plan, and the DFT-S-OFDM transmission plan has low peak average ratio and keeps the characteristic of user's quadrature at frequency domain.

At present, introduced uplink dummy MIMO transmission technology in the LTE communication system, realized that the technical scheme of this technology mainly is based on the virtual MIMO transmission plan of single transmit antenna DFT-S-OFDM.

Fig. 1 is two users' virtual MIMO system based on single transmit antenna DFT-S-OFDM, and wherein, each user terminal (UE) only is equipped with single transmitting antenna, and base station (eNodeB) installs N _rIndividual reception antenna (N among the figure _rValue is 2).Two user terminals use the different information of identical running time-frequency resource transmission under the eNodeB scheduling, two are equipped with single transmit antenna user terminal and constitute a 2 * N with the eNodeB receiver that is equipped with Nr reception antenna _rMimo system, this mimo system is different with traditional mimo system working method, is called virtual MIMO system.In the virtual MIMO system, dispatched users terminal number can be above two simultaneously for eNodeB, but after considering that user terminal surpasses two, eNodeB receiver detection complexity can significantly improve, so only considers the virtual MIMO system that two users constitute in the real system.

Fig. 2 is the transmitter block diagram based on the virtual MIMO of single transmit antenna DFT-S-OFDM.Single transmit antenna DFT-S-OFDM virtual MIMO transmitter and single user DFT-S-OFDM transmitter architecture are identical, and difference only is: two user terminals use the different separately information of identical running time-frequency resource transmission under the eNodeB scheduling; In addition, the channel of two user terminals is estimated, need be carried out particular design the pilot signal of each user terminal for realizing the eNodeB receiver.

Fig. 3 is the virtual MIMO receiver block diagram based on two reception antenna DFT-S-OFDM.In eNodeB, two reception antennas receive two users simultaneously and transmit, and send into baseband processing unit after radio frequency and intermediate frequency process; In baseband processing unit, receiver at first removes Cyclic Prefix, transform to frequency domain by FFT then, through after separating mapping, adopt linear ZF (ZF) or least mean-square error (MMSE) algorithm to carry out frequency domain equalization and handle, at last signal after the equilibrium is transformed into time domain and carries out every user by symbol detection through IDFT.

Compare with single user's transmission means, virtual MIMO system can significantly improve the band efficiency of up link.But, studies show that recently: the DFT-S-OFDM transmission plan based on single antenna can not utilize many antennas to provide spatial emission diversity gain to improve reliability of link transmission, can not utilize many antennas to provide spatial reuse to gain to improve the transmission capacity of link.

In a word, existing virtual MIMO transmission plan can not make full use of multiaerial system provides spatial emission diversity gain, will cause reliability of link transmission relatively poor.

Summary of the invention

In view of this, main purpose of the present invention is to provide a kind of virtual MIMO transmission method and device.This transmission plan can make full use of multiaerial system spatial emission diversity gain is provided, and improves reliability of link transmission.

In order to achieve the above object, the technical scheme of the present invention's proposition is:

A kind of sending method of virtual MIMO, this method comprises:

Two users' terminal UE 1 is used identical running time-frequency resource respectively with UE2, sends information according to identical method;

The method of described transmission information is:

With the signal phasor { X of discrete Fourier transform (DFT) DFT in two adjacent moment k and k+1 output _k, X _K+1Send into space-time block coding simultaneously, and be that unit carries out space-time block coding with the signal phasor, at two code word vector { X of the previous moment k in described adjacent two moment output _k, X _K+1, export two code word vectors in addition at a back moment k+1 in described adjacent two moment

Code word vector X with space-time block coding output _kWith Send into the first emission path and carry out subchannel mapping, contrary fast fourier transform IFFT, insertion Cyclic Prefix, intermediate frequency and radio-frequency transmissions processing; Code word vector X with the output of space-time block coding _K+1With

Send into the second emission path and carry out subchannel mapping, contrary fast fourier transform IFFT, insertion Cyclic Prefix, intermediate frequency and radio-frequency transmissions processing.

A kind of transmitter of virtual MIMO, comprise: modulator, DFT preprocessor, space-time block coding device, first mapper, second mapper, an IFFT processor, the 2nd IFFT processor, the first Cyclic Prefix inserter, the second Cyclic Prefix inserter, first intermediate frequency and rf processor, second intermediate frequency and rf processor, first transmitting antenna and second transmitting antenna

Described DFT preprocessor is used for the signal phasor { X in two adjacent moment k and k+1 generation _k, X _K+1Send into described space-time block coding device simultaneously;

Described space-time block coding device is used to receive the signal phasor { X of described DFT preprocessor _k, X _K+1, and be that unit carries out space-time block coding with the signal phasor, at two code word vector { X of the previous moment k in described adjacent two moment output _k, X _K+1, export two code word vectors in addition at a back moment k+1 in described adjacent two moment

Wherein, with code word vector X _kWith

Export to described first mapper, with code word vector X _K+1With

Export to described second mapper.

A kind of method of reseptance of virtual MIMO, this method comprises:

From the radiofrequency signal of two reception antennas respectively through radio frequency, intermediate frequency process, sampling, Cyclic Prefix remove, fast fourier transform FFT conciliates mapping, obtains first received signal vector on the antenna

With the received signal vector on second antenna

To every reception antenna, with k moment received signal vector

With k+1 moment received signal vector Conjugation

Arrange the corrected received signal that forms every reception antenna by row

N is the reception antenna numbering; The corrected received signal of two reception antennas is arranged the total corrected received signal of formation by row

According to the frequency response of each subchannel between every transmit antennas of the first user terminal UE1 and every reception antenna, all transmitting antenna branches of structure UE1 are clipped to the transmission matrix of two reception antennas

According to the frequency response of each subchannel between every transmit antennas of the second user terminal UE2 and every reception antenna, all transmitting antennas of structure UE2 are to the transmission matrix of each reception antenna

Wherein, H _{M, n}=diag (H _{M, n}(1), H _{M, n}(2) ..., H _{M, n}(j) ... H _{M, n}(N)) represent the diagonal matrix that frequency response constituted of m transmitting antenna of UE1 n all N of reception antenna subchannel, wherein j diagonal element H to the base station _{M, n}(j) represent of the frequency response of m transmitting antenna of UE1 to the individual subchannel of n the reception antenna l=f in base station (j); G _{M, n}=diag (G _{M, n}(1), G _{M, n}(2) ..., G _{M, n}(j) ... G _{M, n}(N)) represent the diagonal matrix that frequency response constituted of m transmitting antenna of UE2 n all N of reception antenna subchannel, wherein j diagonal element G to the base station _{M, n}(j) represent of the frequency response of m transmitting antenna of UE2 to the individual subchannel of n the reception antenna l=f in base station (j), m=1 or 2, l=f (j) is the relation of the channel Mapping in arbitrary emission path when transmitting, l is the subchannel numbering that is mapped to, j is a j component of described arbitrary emission path inner code word vector, j=1 ..., N, N are the counting of DFT conversion of transmitting; According to described transmission matrix, set up linear ZF matrix

It is long-pending to calculate linear ZF matrix and corrected received signal, with result of product as first equivalent received signals

Wherein

Utilize

With

According to With

Obtain second equivalent received signals

With

The structure diagonal matrix

With

Obtain diagonal matrix A and B;

According to

Calculate the transmitting terminal signal phasor { X of UE1 _k, X _K+1Estimated value

Wherein, α (j) is j the diagonal element of A,

And Be respectively

And

J component,

And Be respectively

The top n component and the back N the vector that component constituted;

According to Calculate the transmitting terminal signal phasor { C of UE2 _k, C _K+1Estimated value

Wherein, β (j) is j the diagonal element of B,

And Be respectively

And

J component,

And

Be respectively

The top n component and the back N the vector that component constituted;

Estimated value to described transmitting terminal signal phasor With

Carry out inverse Fourier transform IDFT, detect the estimated value of the emission symbol that obtains UE1 and UE2 again.

A kind of receiver of virtual MIMO, this receiver comprises: with 2 reception antennas 2 receivers, 2 cyclic prefix remover, 2 fft processors, 2 de-mapping devices, space-time joint equalizer, 2 IDFT processors and 2 demodulators one to one;

Arbitrary receiver is used for the signal that receiving end/sending end sends, and carries out exporting to coupled cyclic prefix remover after radio frequency, intermediate frequency and the sampling processing;

Arbitrary cyclic prefix remover is used for removing Cyclic Prefix from the signal that receives, and exports to coupled fft processor;

Arbitrary fft processor is used for that the signal that receives is carried out FFT and handles, and exports to coupled de-mapping device;

Arbitrary de-mapping device is used for the signal that receives obtaining two received signal vectors according to separating mapping with the corresponding mode of transmitting terminal

With

N is the reception antenna numbering of this de-mapping device correspondence; Described space-time joint equalizer is at every reception antenna, with k moment received signal vector With k+1 moment received signal vector

Conjugation

Arrange the corrected received signal that forms every reception antenna by row

N is the reception antenna numbering; The corrected received signal of two reception antennas is arranged the total corrected received signal of formation by row

According to the frequency response of each subchannel between every transmit antennas of the first user terminal UE1 and every reception antenna, all transmitting antenna branches of structure UE1 are clipped to the transmission matrix of two reception antennas According to the frequency response of each subchannel between every transmit antennas of the second user terminal UE2 and every reception antenna, all transmitting antennas of structure UE2 are to the transmission matrix of each reception antenna

Wherein, H _{M, n}=diag (H _{M, n}(1), H _{M, n}(2) ..., H _{M, n}(j) ... H _{M, n}(N)) represent the diagonal matrix that frequency response constituted of m transmitting antenna of UE1 n all N of reception antenna subchannel, wherein j diagonal element H to the base station _{M, n}(j) represent of the frequency response of m transmitting antenna of UE1 to the individual subchannel of n the reception antenna l=f in base station (j); G _{M, n}=diag (G _{M, n}(1), G _{M, n}(2) ..., G _{M, n}(j) ... G _{M, n}(N)) represent the diagonal matrix that frequency response constituted of m transmitting antenna of UE2 n all N of reception antenna subchannel, wherein j diagonal element G to the base station _{M, n}(j) represent of the frequency response of m transmitting antenna of UE2 to the individual subchannel of n the reception antenna l=f in base station (j), m=1 or 2, l=f (j) is the relation of the channel Mapping in arbitrary emission path when transmitting, l is the subchannel numbering that is mapped to, j is a j component of described arbitrary emission path inner code word vector, j=1 ..., N, N are the counting of DFT conversion of transmitting;

According to described transmission matrix, set up linear ZF matrix

It is long-pending to calculate linear ZF matrix and corrected received signal, with result of product as first equivalent received signals

Wherein Utilize

With According to

With

Right

With

Handle, obtain second equivalent received signals

With

The structure diagonal matrix

With

Obtain diagonal matrix A and B; According to

Calculate the transmitting terminal signal phasor { X of UE1 _k, X _K+1Estimated value

And export to coupled IDFT processor, wherein, α (j) is j the diagonal element of A,

And

Be respectively

And

J component,

And

Be respectively

The top n component and the back N the vector that component constituted; According to J=1 ..., N calculates the transmitting terminal signal phasor { C of UE2 _k, C _K+1Estimated value

And export to coupled IDFT processor, wherein, β (j) is j the diagonal element of B,

And Be respectively

And

J component,

And

Be respectively

The top n component and the back N the vector that component constituted;

Described IDFT processor is used for the signal that receives is carried out contrary discrete Fourier transform (DFT) IDFT, and transformation results is exported to coupled demodulator;

Described demodulator is used for carrying out to received signal the estimated value that demodulation obtains launching symbol.

As seen from the above technical solution, among the present invention, at transmitting terminal, UE1 and UE2 dispose many antennas respectively, and use identical running time-frequency resource to send different separately information according to identical sending method, concrete sending method is: the k and the signal phasor { X in the k+1 moment that will obtain through the DFT preliminary treatment _k, X _K+1Send into the space-time block coding device simultaneously and carry out space-time two-dimensional coding, particularly, obtain two code word vector { X at moment k _k, X _K+1, obtain two code word vectors in addition at moment k+1

The code word vector X that moment k is obtained _kThe code word vector that obtains with moment k+1

Send into the first emission path, and handle through subchannel mapping, IFFT computing, insertion Cyclic Prefix and emission; The code word vector X that moment k is obtained _K+1The code word vector that obtains with moment k+1

Send into the second emission path, and handle through subchannel mapping, IFFT computing, insertion Cyclic Prefix and emission.Each user adopts above-mentioned send mode, and an aspect makes signal transmit on two emission paths by space-time block coding, thereby obtains spatial emission diversity gain, improves the reliability of transmission; On the other hand, space-time block coding carries out space-time block coding with vector form, avoids the change of coding codeword vector frequency domain characteristic, thereby the DFT-S-OFDM system that guarantees space-time block coding has the low peak average ratio characteristic.

At receiving terminal, receiver is in the k of each transmission channel and k+1 received signal and carry out channel estimating constantly, and according to the form of transmitting terminal space-time block coding, utilize the channel estimating of received signal and each subchannel to construct the total corrected received signal and the transmission matrix of each reception antenna, utilize the transmission matrix of this total corrected received signal and each reception antenna to calculate equivalent received signals again, and the estimated value of signal after the calculating preliminary treatment, this estimated value is carried out obtaining launching after IDFT handles the estimated value of symbolic vector, subsequently by finishing input by symbol detection.

Description of drawings

Fig. 1 is two users' virtual MIMO system schematic diagram based on single transmit antenna DFT-S-OFDM;

Fig. 2 is the transmitter block diagram based on the virtual MIMO of single transmit antenna DFT-S-OFDM;

Fig. 3 is the virtual MIMO receiver block diagram based on two reception antenna DFT-S-OFDM;

Fig. 4 is two users' virtual MIMO system schematic diagram based on BST-DFT-S-OFDM of the embodiment of the invention one;

The transmitting terminal concrete structure figure that Fig. 5 provides for embodiment one based on two users' virtual MIMO system of BST-DFT-S-OFDM;

The concrete structure schematic diagram of the BST-DFT-S-OFDM virtual MIMO system receiver that Fig. 6 provides for the embodiment of the invention one;

Fig. 7 for the QPSK modulation system place an order user DFT-S-OFDM system with based on the bit error performance of two users' virtual MIMO system under low speed TU channel circumstance of the DFT-S-OFDM of single transmit antenna schematic diagram relatively;

Fig. 8 is for the present invention is based on the bit error performance schematic diagram of two users' virtual MIMO system under low speed TU channel circumstance of BST-DFT-S-OFDM under the QPSK modulation system.

Embodiment

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

Basic thought of the present invention: at transmitting terminal is that every user terminal disposes two transmit antennas, eNodeB receiver configuration N _r(N _r＞1) root reception antenna, under the scheduling of eNodeB receiver, two user terminals use identical running time-frequency resource to transmit different information.Thereby constitute a 4 * N _rVirtual MIMO system, provide spatial emission diversity gain to make full use of multiaerial system, improve reliability of link transmission.

Need to prove, on the DFT-S-OFDM system-based, can directly adopt space-time block code (STBC) or space frequency block coding (SFBC) to construct 2 antenna transmit diversity DFT-S-OFDM transmission plans.These two kinds of transmission plans can obtain full emission diversity gain, but, made based on the DFT-S-OFDM system destruction of STBC or SFBC coding the low peak average ratio characteristic of DFT-S-OFDM system because grouping or space frequency block coding computing change signal frequency-domain characteristic after the DFT preliminary treatment when empty.Therefore should not be based on the DFT-S-OFDM transmission plan of STBC or SFBC coding as LTE system up-link transmission plan.

In the embodiment that the present invention provides, transmitting terminal to the DFT preliminary treatment after signal adopt a kind of new space-time two-dimensional encoding scheme.This scheme is different from traditional encoding scheme based on STBC or SFBC, encode but the pretreated signal phasor of DFT is carried out two dimension in space/time with vector form, below above-mentioned block encoding mode is called space-time block coding (BST), system provided by the invention is called B ST-DFT-S-OFDM virtual MIMO system.Be described in detail below by a pair of this BST-DFT-S-OFDM virtual MIMO system of the embodiment of the invention.

Fig. 4 is two users' virtual MIMO system schematic diagram based on BST-DFT-S-OFDM of the embodiment of the invention one.As shown in Figure 4, in this virtual MIMO system, two transmitting antennas of every UE configuration, two reception antennas of eNodeB receiver configuration, under the scheduling of eNodeB receiver, two UE use identical running time-frequency resource to transmit different information, thereby constitute one 4 * 2 virtual MIMO system.

The transmitting terminal concrete structure figure that Fig. 5 provides for embodiment one based on two users' virtual MIMO system of BST-DFT-S-OFDM, the transmitting terminal of this system is made of the transmitter of two UE, the transmitter architecture of each UE is identical, being convenient narration, below is the transmitter principle that example illustrates the BST-DFT-S-OFDM virtual MIMO system with the transmitter of UE1.

As shown in Figure 5, the transmitter of this UE 1 comprises: modulator, DFT preprocessor, space-time block coding device, first mapper, second mapper, an IFFT processor, the 2nd IFFT processor, the first Cyclic Prefix inserter, the second Cyclic Prefix inserter, first intermediate frequency and rf processor, second intermediate frequency and rf processor, first transmitting antenna and second transmitting antenna.The sending method of BST-DFT-S-OFDM virtual MIMO system of the present invention can be implemented in the transmitter of two UE shown in Figure 5.Below main be the concrete idiographic flow that utilizes this transmitter to send of introducing of example with UE1.

At first, the bit information of UE1 information source output is sent into channel encoder and is carried out chnnel coding, chnnel coding output is sent into modulator and is carried out symbol-modulated, the complex symbol of modulator output is that unit divides into groups with the length N, block length N is identical with subchannel (subcarrier) number that eNodeB distributes to UE1, and k packet of modulation symbols of UE1 is designated as x _k≡ [x _{K, 1}, x _{K, 2}..., x _{K, i}..., x _{K, N}] ^T, wherein, x _{K, i}Represent i modulation symbol in k packet of modulation symbols of UE1, x _kThe output signal vector is designated as X after N point DFT preliminary treatment _k≡ [X _{K, 1}, X _{K, 2}..., X _{K, j}..., X _{K, N}] ^T, X _kWith x _kBe the discrete Fourier transform relation:

$X_{k,j}=\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{x}_{k,i}\&CenterDot;e^{-\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;}\frac{(i-1)\&CenterDot;(j-1)}{N}},j=1,...,N---\left(1\right)$

K and k+1 be the pretreated signal phasor { X of DFT constantly _k, X _K+1Enter the encoding process that the space-time block coding device carries out space-time two-dimensional simultaneously.

Being different from traditional space-time block code that DFT-S-OFDM adopted, is that unit carries out to send signal phasor when the present invention adopts space-time block coding.Particularly, with two signal phasor X _kAnd X _K+1Encode as one group, obtain two code word vector X constantly at k _kAnd X _K+1, obtain two code word vectors in addition constantly at k+1

With

At k constantly, with code word vector { X _k, X _K+1In the first code word vector X _kSend into the 1st emission path transmission, with the second code word vector X _K+1Send into the 2nd emission path transmission; At k+1 constantly, with the code word vector

In the first code word vector

Send into the 1st emission path transmission, with the second code word vector Send into the 2nd emission path transmission, above process is referring to shown in Figure 5.

In frequency domain, can equivalence be the cycle shift operation of corresponding time-domain signal to the conjugate operation of signal in time domain, therefore frequency-region signal is carried out the time domain peak-to-average force ratio characteristic that conjugate operation does not change signal; In addition, in frequency domain, frequency-region signal is got the peak-to-average force ratio characteristic that the negative sign computing also can not change time-domain signal, as seen, according to space-time block coding among the present invention, output code word vector

With coded input signal vector { X _k, X _K+1Has identical peak-to-average force ratio characteristic in time domain.

Handle in such a way after code word vector behind the space-time block coding sent into the emission path:

Code word vector behind the piece Space Time Coding transmits by N the continuous subchannel (or discontinuous subchannel) that the channel Mapping device is mapped to system assignment, and the mapper input is expressed as with output relation:

l＝f(j)，j＝1，...，N (2)

Wherein, f () represents mapping function, and (2) show signal

About j component be mapped to l|l=f (j), j=1 ..., N} subchannel transmission.The 1st emission path k and k+1 are shone upon back signal X constantly _kAnd

The 2nd emission path k and k+1 shine upon back signal X constantly _K+1And Send into IFFT processor, Cyclic Prefix inserter and intermediate frequency and rf processor successively, send into two antenna emissions at last respectively.

Step of transmitting and the UE1 of UE2 are identical, just are convenient narration subsequently, and k and k+1 packet of modulation symbols of UE2 emission are designated as { c _k, c _K+1, wherein, c _k≡ [c _{K, 1}, c _{K, 2}..., c _{K, i}..., c _{K, N}] ^T{ c _k, c _K+1Signal phasor is designated as { C after N point DFT preliminary treatment _k, C _K+1, C wherein _k≡ [C _{K, 1}, C _{K, 2}..., C _{K, j}..., C _{K, N}] ^T, the code word vector representation is { C behind the space-time block coding _k, C _K+1And

In addition, subchannel and UE1 that UE2 emission information is used are identical, promptly two user terminal use subchannels be l|l=f (j), j=1 ..., N}.

The above-mentioned concrete formation of BST-DFT-S-OFDM virtual MIMO system transmitter in the embodiment of the invention one and the concrete signalling formula of being.

Next, reception testing process and the receiver that carries out at above-mentioned transmission signal provided by the invention is described in detail.

The concrete structure schematic diagram of the BST-DFT-S-OFDM virtual MIMO system receiver that Fig. 6 provides for the embodiment of the invention one.As shown in Figure 6, this receiver comprises: 2 receivers, 2 cyclic prefix remover, 2 fft processors, 2 de-mapping devices, space-time joint equalizer, 2 IDFT processors and 2 demodulators.The BST-DFT-S-OFDM virtual MIMO system method of reseptance of the embodiment of the invention one can be implemented in receiver shown in Figure 6.Below just concrete the introduction utilize this receiver to carry out signal to receive the idiographic flow that detects.

As seen from Figure 6, have 2 reception paths during receiver hollow before the joint equalization device, each receives the corresponding reception antenna of path.When carrying out signal reception processing, each processing mode that receives path is identical, and receiving path with one of them here is that example is introduced.

Particularly, receiver receives radiofrequency signal from antenna constantly at k and k+1, and after radio frequency, intermediate frequency process, sample and obtain digital baseband signal, utilize cyclic prefix remover that digital baseband signal is removed Cyclic Prefix again, carry out the FFT conversion process that L is ordered by fft processor then, extracted the received signal of N subchannel at last by de-mapping device, wherein, it is corresponding with the mapping mode of transmitting terminal to separate mapping mode.If n reception path k and k+1 de-mapping device output signal vector representation constantly is

Wherein,

Represent k n all N of reception path subchannel received signal vectors constantly,

The signal of representing the individual subchannel of k moment n reception path l=f (j) to receive.

As above promptly obtain the transmission signals that each receives path, these transmission signals are sent in the space-time joint equalizer.In the space-time joint equalizer each subchannel transmission signal of two reception paths is merged and equilibrium treatment, space-time joint equalizer output signal vector is designated as

With

Be UE1 k and the k+1 vector { X that transmits constantly _k, X _K+1Estimated value;

Be UE2 k and the k+1 vector { C that transmits constantly _k, C _K+1Estimated value.As seen, equilibrium treatment eNodeB receiver is realized two separation that user terminal transmits when uniting sky.First user terminal UE1 signal after the separation

Sending into the IDFT processor that N orders respectively obtains

Second user terminal UE2 signal after the separation Sending into the IDFT processor that N orders respectively obtains

At last, in demodulator respectively to the first user UE1 received signal vector

Each component carry out Maximum Likelihood Detection and can obtain UE1 emission symbol { x _k, x _K+1Estimated value To the second user UE2 received signal vector

Each component carry out the emission symbol { c that Maximum Likelihood Detection can obtain second user _k, c _K+1Estimated value Wherein,

With ${\hat{c}}_k\&equiv;{[{\hat{c}}_{k,1},{\hat{c}}_{k,2},...,{\hat{c}}_{k,i},...,{\hat{c}}_{k,N}]}^T.$

If transmitter uses channel encoder before modulator, then at receiving terminal according to first user's received signal vector

Can obtain to launch the soft decision information of symbol, soft decision information can obtain the estimated value that first user launches bit sequence after further sending into channel decoder, correspondingly, adopts same procedure, can obtain the estimated value that second user launches bit sequence.

Below the operation principle of derivation space-time joint equalizer.

Adopted two reception antennas among the embodiment one, this moment, the n value was 2, then signal phasor

Can be expressed as:

$\left[\begin{array}{c}{Y}_k^{\left(1\right)}\\ Y_{k+1}^{{\left(1\right)}^{*}}\\ Y_k^{\left(2\right)}\\ Y_{k+1}^{{\left(2\right)}^{*}}\end{array}\right]=\left[\begin{array}{cccc}{\mathrm{<figure-callout\; id="1"\; label="H"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">H</figure-callout>}}_{\mathrm{1,1}}& {\mathrm{<figure-callout\; id="2"\; label="H"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">H</figure-callout>}}_{\mathrm{2,1}}& {\mathrm{<figure-callout\; id="1"\; label="G"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">G</figure-callout>}}_{\mathrm{1,1}}& {\mathrm{<figure-callout\; id="2"\; label="G"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">G</figure-callout>}}_{\mathrm{2,1}}\\ {\mathrm{<figure-callout\; id="2"\; label="H"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">\; <figure-callout\; id="1"\; label="H"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">H</figure-callout>\; </figure-callout>}}_{\mathrm{2,1}}^{*}& -{\mathrm{<figure-callout\; id="1"\; label="H"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">\; <figure-callout\; id="1"\; label="H"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">H</figure-callout>\; </figure-callout>}}_{1,1}^{*}& {\mathrm{<figure-callout\; id="2"\; label="G"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">\; <figure-callout\; id="1"\; label="G"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">G</figure-callout>\; </figure-callout>}}_{\mathrm{2,1}}^{*}& -{\mathrm{<figure-callout\; id="1"\; label="G"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">\; <figure-callout\; id="1"\; label="G"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">G</figure-callout>\; </figure-callout>}}_{\mathrm{1,1}}^{*}\\ {\mathrm{<figure-callout\; id="1"\; label="H"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">H</figure-callout>}}_{\mathrm{1,2}}& {\mathrm{<figure-callout\; id="2"\; label="H"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">H</figure-callout>}}_{\mathrm{2,2}}& {\mathrm{<figure-callout\; id="1"\; label="G"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">G</figure-callout>}}_{\mathrm{1,2}}& {\mathrm{<figure-callout\; id="2"\; label="G"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">G</figure-callout>}}_{\mathrm{2,2}}\\ {\mathrm{<figure-callout\; id="2"\; label="H"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">\; <figure-callout\; id="2"\; label="H"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">H</figure-callout>\; </figure-callout>}}_{\mathrm{2,2}}^{*}& -{\mathrm{<figure-callout\; id="1"\; label="H"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">\; <figure-callout\; id="2"\; label="H"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">H</figure-callout>\; </figure-callout>}}_{\mathrm{1,2}}^{*}& {\mathrm{<figure-callout\; id="2"\; label="G"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">\; <figure-callout\; id="2"\; label="G"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">G</figure-callout>\; </figure-callout>}}_{\mathrm{2,2}}^{*}& -{\mathrm{<figure-callout\; id="1"\; label="G"\; filenames="H2009100775112E0000023.png"\; state="\{\{state\}\}">\; <figure-callout\; id="2"\; label="G"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">G</figure-callout>\; </figure-callout>}}_{\mathrm{1,2}}^{*}\end{array}\right]\left[\begin{array}{c}{X}_k\\ X_{k+1}\\ C_k\\ C_{k+1}\end{array}\right]+\left[\begin{array}{c}{N}_k^{\left(1\right)}\\ N_{k+1}^{{\left(1\right)}^{*}}\\ N_k^{\left(2\right)}\\ N_{k+1}^{{\left(2\right)}^{*}}\end{array}\right]---\left(3\right)$

Wherein, H _{M, n}=diag (H _{M, n}(1), H _{M, n}(2) ..., H _{M, n}(j) ... H _{M, n}(N)) represent the diagonal matrix that frequency response constituted of m transmitting antenna of UE1 n all N of reception antenna subchannel, j diagonal element H to the base station _{M, n}(j) represent of the frequency response of m transmitting antenna of UE1 to the individual subchannel of n the reception antenna l=f in base station (j);

G _{M, n}=diag (G _{M, n}(1), G _{M, n}(2) ..., G _{M, n}(j) ... G _{M, n}(N)) represent the diagonal matrix that frequency response constituted of m transmitting antenna of UE2 n all N of reception antenna subchannel, j diagonal element G to the base station _{M, n}(j) represent of the frequency response of m transmitting antenna of UE2 to the individual subchannel of n the reception antenna l=f in base station (j); Wherein, the UE1 transmission signals is { X _k, X _K+1, the UE2 transmission signals is { C _k, C _K+1.

By the observation Channel Transmission matrix in (3) formula as can be known

Has class Alamouti characteristic.(3) formula can further be expressed as the matrix in block form form:

$\left[\begin{array}{c}{Y}^{\left(1\right)}\\ Y^{\left(2\right)}\end{array}\right]=\left[\begin{array}{cc}{\mathrm{\&Lambda;}}_{\mathrm{1,1}}& {\mathrm{\&Lambda;}}_{\mathrm{1,2}}\\ {\mathrm{\&Lambda;}}_{\mathrm{2,1}}& {\mathrm{\&Lambda;}}_{\mathrm{2,2}}\end{array}\right]\left[\begin{array}{c}X\\ C\end{array}\right]+\left[\begin{array}{c}{N}^{\left(1\right)}\\ N^{\left(2\right)}\end{array}\right]---\left(4\right)$

Wherein,

X=[X _k ^TX _K+1 ^T] ^T, C=[C _k ^TC _K+1 ^T] ^T(4) formula further is expressed as:

Y＝ΛZ+N (5)

Wherein,

Further introduce the linear ZF matrix of two users:

$E=\left[\begin{array}{cc}{I}_{2N}& -{\mathrm{\&Lambda;}}_{\mathrm{1,2}}{\mathrm{\&Lambda;}}_{\mathrm{2,2}}^{-1}\\ -{\mathrm{\&Lambda;}}_{\mathrm{2,1}}{\mathrm{\&Lambda;}}_{\mathrm{1,1}}^{-1}& I_{2N}\end{array}\right]---\left(6\right)$

And the following signal phasor of structure:

$\tilde{Y}=\mathrm{EY}$

$=\mathrm{E\&Lambda;Z}+\mathrm{EN}---\left(7\right)$

$=\mathrm{E\&Lambda;Z}+\tilde{N}$

(7) launch to be expressed as:

$\left[\begin{array}{c}{\tilde{Y}}_1\\ {\tilde{Y}}_2\end{array}\right]=\left[\begin{array}{cc}\mathrm{\&Sigma;}& 0\\ 0& \mathrm{\&Delta;}\end{array}\right]\left[\begin{array}{c}X\\ C\end{array}\right]+\left[\begin{array}{c}{\tilde{N}}_1\\ {\tilde{N}}_2\end{array}\right]---\left(8\right)$

Wherein, $\mathrm{\&Sigma;}={\mathrm{\&Lambda;}}_{\mathrm{1,1}}-{\mathrm{\&Lambda;}}_{\mathrm{1,2}}{\mathrm{\&Lambda;}}_{\mathrm{2,2}}^{-1}{\mathrm{\&Lambda;}}_{\mathrm{2,1}},$ $\mathrm{\&Delta;}={\mathrm{\&Lambda;}}_{\mathrm{2,2}}-{\mathrm{\&Lambda;}}_{2,1}{\mathrm{\&Lambda;}}_{1,1}^{-1}{\mathrm{\&Lambda;}}_{1,2},$ $\tilde{Y}={\left[\begin{array}{cc}{\tilde{Y}}_1^T& {\tilde{Y}}_2^T\end{array}\right]}^T.$

(8) formula further is expressed as:

${\tilde{Y}}_1=\mathrm{\&Sigma;X}+{\tilde{N}}_1---\left(9\right)$

${\tilde{Y}}_2=\mathrm{\&Delta;C}+{\tilde{N}}_2$

Further utilize matrix ∑ and Δ to have class Alamouti characteristic, (9) formula is handled in such a way:

${\widetilde{\stackrel{~}{Y}}}_1={\mathrm{\&Sigma;}}^H{\tilde{Y}}_1---\left(10\right)$

$={\mathrm{\&Sigma;}}^H\mathrm{\&Sigma;X}+{\mathrm{\&Sigma;}}^H{\tilde{N}}_1$

${\widetilde{\stackrel{~}{Y}}}_2={\mathrm{\&Delta;}}^H{\tilde{Y}}_2---\left(11\right)$

$={\mathrm{\&Delta;}}^H\mathrm{\&Delta;C}+{\mathrm{\&Delta;}}^H{\tilde{N}}_2$

Utilize matrix ∑ and Δ to be class Alamouti matrix characteristic, as can be known

And

Be diagonal matrix.Then (10) and (11) can be expressed as:

${\widetilde{\stackrel{~}{Y}}}_{\mathrm{1,1}}=A{X}_k+{\widetilde{\stackrel{~}{N}}}_{\mathrm{1,1}}---\left(12\right)$

${\widetilde{\stackrel{~}{Y}}}_{1,2}=A{X}_{k+1}+{\widetilde{\stackrel{~}{N}}}_{1,2}$

${\widetilde{\stackrel{~}{Y}}}_{2,1}={\mathrm{BC}}_k+{\widetilde{\stackrel{~}{N}}}_{\mathrm{2,1}}---\left(13\right)$

${\widetilde{\stackrel{~}{Y}}}_{\mathrm{2,2}}={\mathrm{BC}}_{k+1}+{\widetilde{\stackrel{~}{N}}}_{\mathrm{2,2}}$

Wherein,

Utilize A and B matrix to be diagonal matrix, (12) formula and (13) formula are designated as the scalar form:

$\left\{\begin{array}{c}{\widetilde{\stackrel{~}{Y}}}_{\mathrm{1,1},j}=\mathrm{\&alpha;}\left(j\right)X_{k,j}+{\widetilde{\stackrel{~}{N}}}_{\mathrm{1,1},j}\\ {\widetilde{\stackrel{~}{Y}}}_{\mathrm{1,2},j}=\mathrm{\&alpha;}\left(j\right)X_{k+1,j}+{\widetilde{\stackrel{~}{N}}}_{\mathrm{1,2},j}\end{array}\right.,j=1,...,N---\left(14\right)$

$\left\{\begin{array}{c}{\widetilde{\stackrel{~}{Y}}}_{\mathrm{2,1},j}=\mathrm{\&beta;}\left(j\right)C_{k,j}+{\widetilde{\stackrel{~}{N}}}_{\mathrm{2,1},j}\\ {\widetilde{\stackrel{~}{Y}}}_{\mathrm{2,2},j}=\mathrm{\&beta;}\left(j\right)C_{k+1,j}+{\widetilde{\stackrel{~}{N}}}_{\mathrm{2,2},j}\end{array}\right.,j=1,...,N---\left(15\right)$

Wherein,

And Be respectively

And

J component.α (j) is j the diagonal element of A,

And Be respectively And

J component; And

Be respectively

And

J component.β (j) is j the diagonal element of B,

And

Be respectively

And

J component; (14) formula and (15) formula are carried out respectively obtaining X after the scalar equilibrium _{K, j}, X _{K+1, j}, C _{K, j}And C _{K+1, j}Estimator:

$\left\{\begin{array}{c}{\tilde{X}}_{k,j}=\frac{1}{\mathrm{\&alpha;}\left(j\right)+{{\mathrm{\&sigma;}}_{\mathrm{1,1},\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">j</figure-callout>}}}^2}\&CenterDot;{\widetilde{\stackrel{~}{Y}}}_{\mathrm{1,1},j}\\ {\tilde{X}}_{k+1,j}=\frac{1}{\mathrm{\&alpha;}\left(j\right)+{{\mathrm{\&sigma;}}_{\mathrm{1,2},\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">j</figure-callout>}}}^2}\&CenterDot;{\widetilde{\stackrel{~}{Y}}}_{\mathrm{1,2},j}\end{array}\right.,j=1,...,N---\left(16\right)$

$\left\{\begin{array}{c}{\tilde{C}}_{k,j}=\frac{1}{\mathrm{\&beta;}\left(j\right)+{{\mathrm{\&sigma;}}_{\mathrm{2,1},\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">j</figure-callout>}}}^2}\&CenterDot;{\widetilde{\stackrel{~}{Y}}}_{\mathrm{2,1},j}\\ {\tilde{C}}_{k+1,j}=\frac{1}{\mathrm{\&beta;}\left(j\right)+{{\mathrm{\&sigma;}}_{\mathrm{2,2},\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="H2009100775112E0000031.png,H2009100775112E0000032.png"\; state="\{\{state\}\}">j</figure-callout>}}}^2}\&CenterDot;{\widetilde{\stackrel{~}{Y}}}_{\mathrm{2,2},j}\end{array}\right.,j=1,...,N---\left(17\right)$

Wherein, σ _{S, t, j} ²For

Noise variance.The estimated value table that (16) and (17) are obtained is shown vector form and obtains

With

Wherein, ${\tilde{X}}_k\&equiv;{[{\tilde{X}}_{k,1},{\tilde{X}}_{k,2},...{\tilde{X}}_{k,j},...,{\tilde{X}}_{k,N}]}^T,$ ${\tilde{X}}_{k+1}\&equiv;{[{\tilde{X}}_{k+1,1},{\tilde{X}}_{k+1,2},...{\tilde{X}}_{k+1,j},...,{\tilde{X}}_{k+1,N}]}^T,$ ${\tilde{C}}_k\&equiv;{[{\tilde{C}}_{k,1},{\tilde{C}}_{k,2},...{\tilde{C}}_{k,j},...,{\tilde{C}}_{k,N}]}^T,$ ${\tilde{C}}_{k+1}\&equiv;{[{\tilde{C}}_{k+1,1},{\tilde{C}}_{k+1,2},...{\tilde{C}}_{k+1,j},...,{\tilde{C}}_{k+1,N}]}^T.$

By above-mentioned derivation as can be known, can utilize signal according to formula (7)

With channel information H _1,1, H _1,2, H _2,1, H _2,2, G _1,1, G _1,2, G _2,1And G _2,2Merge processing, obtain corrected signal for the first time

With

Again according to formula (10), (11) to corrected signal

With

Handle, obtain corrected signal for the second time With

Again according to formula (16) and (17) to the corrected signal second time

With

Carry out equilibrium, thereby obtain

With

Estimated value.

Obtain by the space-time joint equalization algorithm in the concrete receiver

With

The mode of estimated value can be summarized as:

Determine that k the 1st receives N subchannel received signal of path constantly

Determine that k+1 the 1st receives N subchannel received signal of path constantly

And conjugated signal

Determine that k the 2nd receives N subchannel received signal of path constantly

Determine that k+1 the 2nd receives N subchannel received signal of path constantly

And conjugated signal

And with received signal

And conjugated signal

Arrange the form that forms corrected received signal Y by row, promptly

According to the frequency response of each subchannel between every transmit antennas of the first user terminal UE1 and every reception antenna, all transmitting antenna branches of structure UE1 are clipped to the transmission matrix of two reception antennas

According to the frequency response of each subchannel between every transmit antennas of the second user terminal UE2 and every reception antenna, all transmitting antennas of structure UE2 are to the transmission matrix of each reception antenna

According to described transmission matrix, set up linear ZF matrix

It is long-pending to calculate linear ZF matrix and corrected received signal, with result of product as first equivalent received signals

Wherein

Utilize

With

According to

With

Right

With Handle, obtain second equivalent received signals With

The structure diagonal matrix

With Obtain diagonal matrix A and B;

Utilize formula (16) and (17) to calculate the transmitting terminal signal phasor

With

Estimated value.

Above-mentionedly be the concrete mode that receiving terminal is handled and detected baseband signal under the two reception antenna situations.The above-mentioned reception principle of two reception antennas can be generalized to the situation of 4/8 reception antenna, and along with the increase of eNodeB place reception antenna number, receiver obtains diversity gain significantly to be increased, and the link transmission reliability is further improved.In view of the reception principle under the situation of 4/8 reception antenna is identical, concrete processing mode is similar, does not repeat them here.

Signal transmission the having carried out emulation that the present invention constitutes utilizing above-mentioned method of sending and receiving is to verify the transmission performance of BST-DFT-S-OFDM of the present invention system.Below contrast existing transmission plan and the transmission plan that the present invention is based on two users' virtual MIMO system of BST-DFT-S-OFDM from link transmission error performance angle.

Fig. 7 for the QPSK modulation system place an order user DFT-S-OFDM system with based on DFT-S-OFDM two users virtual MIMO system bit error performance of single transmit antenna schematic diagram relatively.Concrete simulation parameter is that TU channel, terminal movement velocity are 3km/h, no chnnel coding.Curve 701 is the relation curve based on the signal to noise ratio (snr) of UE1 in the virtual MIMO system of DFT-S-OFDM and the error rate (BER), curve 702 is based on the signal to noise ratio of UE2 in the virtual MIMO system of DFT-S-OFDM and the relation curve of the error rate, and curve 703 is based on the signal to noise ratio of single user's single transmit antenna two reception antenna systems of DFT-S-OFDM and the relation curve of the error rate.By above-mentioned three curves as seen: error performance is 10 ^-3Under the situation, single user DFT-S-OFDM transmission required signal-to-noise ratio is 10.5dB, and transmit required signal to noise ratio based on the virtual MIMO of DFT-S-OFDM is 16.5dB, i.e. virtual MIMO transmission based on DFT-S-OFDM needs volume to pay the cost of 6 decibels of signal to noise ratios, just can be so that the uplink band utilance increases by 1 times.

Fig. 8 is for the present invention is based on the bit error performance schematic diagram of two users' virtual MIMO system under low speed TU channel circumstance of BST-DFT-S-OFDM under the QPSK modulation system.

Concrete simulation parameter is that TU channel, terminal movement velocity are 3km/h, no chnnel coding.Curve 801 and 802 is respectively based on the signal to noise ratio of UE1 and UE2 in the virtual MIMO system of BST-DFT-S-OFDM and the relation curve of the error rate.803 is signal to noise ratio and the error transmissions performance based on single user 2 emissions 2 reception antenna systems of DFT-S-OFDM.

The curve of comparison diagram 7 and Fig. 8 is as can be known: the bit error performance is 10 ^-3Under the situation, transmitting required signal to noise ratio based on the virtual MIMO of BST-DFT-S-OFDM is 14.5dB, and transmit required signal to noise ratio based on the virtual MIMO of DFT-S-OFDM is 16.5dB, as seen the virtual MIMO transmission plan detection threshold that the present invention is based on BST-DFT-S-OFDM is lower than traditional virtual MIMO transmission plan based on DFT-S-OFDM, promptly with respect to the single antenna virtual MIMO system, the present invention can obtain higher link transmission reliability.

In sum, more than be preferred embodiment of the present invention only, be 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 (4)

1. the sending method of a virtual MIMO, this method comprises:

Two users' terminal UE 1 is used identical running time-frequency resource respectively with UE2, sends information according to identical method;

It is characterized in that the method for described transmission information is:

With the signal phasor { X of discrete Fourier transform (DFT) DFT in two adjacent moment k and k+1 output _k, X _K+1Send into space-time block coding simultaneously, and be that unit carries out space-time block coding with the signal phasor, at two code word vector { X of the previous moment k in described adjacent two moment output _k, X _K+1, export two code word vectors in addition at a back moment k+1 in described adjacent two moment

Code word vector X with space-time block coding output _kWith

Send into the first emission path and carry out subchannel mapping, contrary fast fourier transform IFFT, insertion Cyclic Prefix, intermediate frequency and radio-frequency transmissions processing; Code word vector X with the output of space-time block coding _K+1With

Send into the second emission path and carry out subchannel mapping, contrary fast fourier transform IFFT, insertion Cyclic Prefix, intermediate frequency and radio-frequency transmissions processing.

2. the transmitter of a virtual MIMO, comprise: modulator, DFT preprocessor, space-time block coding device, first mapper, second mapper, an IFFT processor, the 2nd IFFT processor, the first Cyclic Prefix inserter, the second Cyclic Prefix inserter, first intermediate frequency and rf processor, second intermediate frequency and rf processor, first transmitting antenna and second transmitting antenna, it is characterized in that

Described DFT preprocessor is used for the signal phasor { X in two adjacent moment k and k+1 generation _k, X _K+1Send into described space-time block coding device simultaneously;

Described space-time block coding device is used to receive the signal phasor { X of described DFT preprocessor _k, X _K+1, and be that unit carries out space-time block coding with the signal phasor, at two code word vector { X of the previous moment k in described adjacent two moment output _k, X _K+1, export two code word vectors in addition at a back moment k+1 in described adjacent two moment

Wherein, with code word vector X _kWith

Export to described first mapper, with code word vector X _K+1With Export to described second mapper.

3. the method for reseptance of a virtual MIMO is characterized in that, this method comprises:

From the radiofrequency signal of two reception antennas respectively through radio frequency, intermediate frequency process, sampling, Cyclic Prefix remove, fast fourier transform FFT conciliates mapping, obtains first received signal vector on the antenna

With the received signal vector on second antenna

To every reception antenna, with k moment received signal vector

With k+1 moment received signal vector

Conjugation

Arrange the corrected received signal that forms every reception antenna by row

N is the reception antenna numbering; The corrected received signal of two reception antennas is arranged the total corrected received signal of formation by row

According to the frequency response of each subchannel between every transmit antennas of the first user terminal UE1 and every reception antenna, all transmitting antenna branches of structure UE1 are clipped to the transmission matrix of two reception antennas

According to the frequency response of each subchannel between every transmit antennas of the second user terminal UE2 and every reception antenna, all transmitting antennas of structure UE2 are to the transmission matrix of each reception antenna

Wherein, H _{M, n}=diag (H _{M, n}(1), H _{M, n}(2) .., H _{M, n}(j) ... H _{M, n}(N)) represent the diagonal matrix that frequency response constituted of m transmitting antenna of UE1 n all N of reception antenna subchannel, wherein j diagonal element H to the base station _{M, n}(j) represent of the frequency response of m transmitting antenna of UE1 to the individual subchannel of n the reception antenna l=f in base station (j); G _{M, n}=diag (G _{M, n}(1), G _{M, n}(2) ..., G _{M, n}(j) ... G _{M, n}(N)) represent the diagonal matrix that frequency response constituted of m transmitting antenna of UE2 n all N of reception antenna subchannel, wherein j diagonal element G to the base station _{M, n}(j) represent of the frequency response of m transmitting antenna of UE2 to the individual subchannel of n the reception antenna l=f in base station (j), m=1 or 2, l=f (j) is the relation of the channel Mapping in arbitrary emission path when transmitting, l is the subchannel numbering that is mapped to, j is a j component of described arbitrary emission path inner code word vector, j=1 ..., N, N are the counting of DFT conversion of transmitting;

According to described transmission matrix, set up linear ZF matrix

It is long-pending to calculate linear ZF matrix and corrected received signal, with result of product as first equivalent received signals

Wherein

Utilize

With

According to

With

Obtain second equivalent received signals

With

The structure diagonal matrix

With

Obtain diagonal matrix A and B;

According to

J=1 .., N, the transmitting terminal signal phasor { X of calculating UE1 _k, X _K+1Estimated value

Wherein, α (j) is j the diagonal element of A,

And Be respectively And

J component, And

Be respectively The top n component and the back N the vector that component constituted;

According to J=1 ..., N calculates the transmitting terminal signal phasor { C of UE2 _k, C _K+1Estimated value

Wherein, β (j) is j the diagonal element of B,

And

Be respectively

And

J component,

And

Be respectively

The top n component and the back N the vector that component constituted;

Estimated value to described transmitting terminal signal phasor

With

Carry out inverse Fourier transform IDFT, detect the estimated value of the emission symbol that obtains UE1 and UE2 again.

4. the receiver of a virtual MIMO, it is characterized in that this receiver comprises: with 2 reception antennas 2 receivers, 2 cyclic prefix remover, 2 fft processors, 2 de-mapping devices, space-time joint equalizer, 2 IDFT processors and 2 demodulators one to one;

Arbitrary receiver is used for the signal that receiving end/sending end sends, and carries out exporting to coupled cyclic prefix remover after radio frequency, intermediate frequency and the sampling processing;

Arbitrary cyclic prefix remover is used for removing Cyclic Prefix from the signal that receives, and exports to coupled fft processor;

Arbitrary fft processor is used for that the signal that receives is carried out FFT and handles, and exports to coupled de-mapping device;

Arbitrary de-mapping device is used for the signal that receives obtaining two received signal vectors according to separating mapping with the corresponding mode of transmitting terminal

With N is the reception antenna numbering of this de-mapping device correspondence;

Described space-time joint equalizer is at every reception antenna, with k moment received signal vector

With k+1 moment received signal vector

Conjugation

Arrange the corrected received signal that forms every reception antenna by row

N is the reception antenna numbering; The corrected received signal of two reception antennas is arranged the total corrected received signal of formation by row

According to the frequency response of each subchannel between every transmit antennas of the first user terminal UE1 and every reception antenna, all transmitting antenna branches of structure UE1 are clipped to the transmission matrix of two reception antennas

According to the frequency response of each subchannel between every transmit antennas of the second user terminal UE2 and every reception antenna, all transmitting antennas of structure UE2 are to the transmission matrix of each reception antenna

Wherein, H _{M, n}=diag (H _{M, n}(1), H _{M, n}(2) ..., H _{M, n}(j) ... H _{M, n}(N)) represent the diagonal matrix that frequency response constituted of m transmitting antenna of UE1 n all N of reception antenna subchannel, wherein j diagonal element H to the base station _{M, n}(j) represent of the frequency response of m transmitting antenna of UE1 to the individual subchannel of n the reception antenna l=f in base station (j); G _{M, n}=diag (G _{M, n}(1), G _{M, n}(2) .., G _{M, n}(j) ... G _{M, n}(N)) represent the diagonal matrix that frequency response constituted of m transmitting antenna of UE2 n all N of reception antenna subchannel, wherein j diagonal element G to the base station _{M, n}(j) represent of the frequency response of m transmitting antenna of UE2 to the individual subchannel of n the reception antenna l=f in base station (j), m=1 or 2, l=f (j) is the relation of the channel Mapping in arbitrary emission path when transmitting, l is the subchannel numbering that is mapped to, j is a j component of described arbitrary emission path inner code word vector, j=1 ..., N, N are the counting of DFT conversion of transmitting;

According to described transmission matrix, set up linear ZF matrix

It is long-pending to calculate linear ZF matrix and corrected received signal, with result of product as first equivalent received signals

Wherein

Utilize With

According to

With

Right

With

Handle, obtain second equivalent received signals

With

The structure diagonal matrix

With Obtain diagonal matrix A and B; According to

J=1 ..., N, the transmitting terminal signal phasor { X of calculating UE1 _k, X _K+1Estimated value

And export to coupled IDFT processor, wherein, α (j) is j the diagonal element of A,

And

Be respectively

And

J component,

And

Be respectively

The top n component and the back N the vector that component constituted; According to

J=1 ..., N calculates the transmitting terminal signal phasor { C of UE2 _k, C _K+1Estimated value

And export to coupled IDFT processor, wherein, β (j) is j the diagonal element of B,

And

Be respectively

And

J component,

And

Be respectively

The top n component and the back N the vector that component constituted;

Described IDFT processor is used for the signal that receives is carried out contrary discrete Fourier transform (DFT) IDFT, and transformation results is exported to coupled demodulator;

Described demodulator is used for carrying out to received signal the estimated value that demodulation obtains launching symbol.

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