CN103200141B - Based on the co-channel full duplex mimo system self feed back disturbance restraining method of spatial decomposition - Google Patents

Abstract

The invention discloses a kind of co-channel full duplex mimo system self feed back disturbance restraining method based on spatial decomposition, the signal code cycle is greater than for self feed back channel maximum delay, make transmitting filter and receiving filter matrix be orthogonal to each multipath channel matrix, the transmission namely after design and receiving filter can suppress the self feed back of each multipath to be disturbed.For self feed back interference matrix full rank, self feed back interference space is decomposed into two orthogonal subspaces, first design sends or receiving filter suppress the self feed back interference in a certain subspace after more optionally design to receive or transmitting filter suppresses residual self feed back interference.The dimension that the transmission of the present invention's design and the self feed back that suppresses of receiving filter are disturbed be less than or equal to self feed back interference matrix open into the dimension in space, thus when self feed back interference matrix full rank and its multidiameter delay are greater than the signal code cycle, make part to self feed back interference to suppress, suppress even completely.

Description

Based on the co-channel full duplex mimo system self feed back disturbance restraining method of spatial decomposition

Technical field

The invention belongs to wireless communication technology field, more specifically say, relate to a kind of co-channel full duplex mimo system self feed back disturbance restraining method based on spatial decomposition.

Background technology

At wireless communication field, co-channel full duplex MIMO(Multiple-Input Multiple-Output, multiple-input and multiple-output) system mainly plays the effect of relaying amplifying signal, is used widely in the voice scenes such as video conference.Along with the development of 3G, 4G mobile radio system, the relay station based on co-channel full duplex mimo system and junction network are there is especially.Because co-channel full duplex mimo system is with the work while of frequently, the signal that transmitting antenna sends will be received antenna and receive, and this phenomenon is called as self feed back interference.When transmitting antenna and reception antenna isolation inadequate time, self feed back interference effect message capacity will be caused even to communicate success rate.

Spatial domain cancellation technology is mainly through Signal reception filter in design co-channel full duplex mimo system and transmitting filter realize.Fig. 1 is that in typical co-channel full duplex mimo system, self feed back interference spatial domain suppresses structural representation.As shown in Figure 1, N _rrxand N _rtxbe respectively co-channel full duplex mimo system reception antenna number and number of transmit antennas, with for Received signal strength in relay station after receiving filter and send signal at the signal beam number before transmitting filter, the dimension of C representing matrix.Source to co-channel full duplex system mimo system channel is self feed back channel is n _stxfor source number of transmit antennas, L is the multipath number of self feed back interference signal time delay equal symbol cycle integral multiple. for co-channel full duplex mimo system Received signal strength, for passing through receiving filter signal, for the transmission signal before transmitting filter, for sending signal.Then can obtain for the n-th moment during L=1: $\hat{r}\left[n\right]=G_{\mathrm{rx}}{H}_{\mathrm{SR}}r\left[n\right]+G_{\mathrm{rx}}{H}_{\mathrm{LI}}{G}_{\mathrm{tx}}\hat{t}\left[n\right],$ Wherein for self feed back interference signal.

Existing co-channel full duplex mimo system self feed back interference spatial domain cancellation technology needs channel prior information, mainly contain ZF (Zero Forcing, ZF) algorithm, MMSE (Minimum Mean Square Error, least mean-square error) algorithm and BS (Beaming Selection, sky line options) algorithm scheduling algorithm.But there are two large shortcomings in existing algorithm: 1) can not be applied to self feed back channel matrix H _lIthe scene of full rank; 2) do not propose the self feed back disturbance restraining method for the channel maximum multipath time delay is-greater-than symbol cycle, namely existing algorithm only considered the scene of L=1.

Summary of the invention

The object of the invention is to overcome the deficiencies in the prior art, a kind of co-channel full duplex mimo system self feed back disturbance restraining method based on spatial decomposition is provided, according to self feed back interference channel design transmitting filter or receiving filter, when self feed back interference matrix full rank and its multidiameter delay are greater than the signal code cycle, part can be made to self feed back interference to suppress, suppress even completely.

For achieving the above object, the present invention is based on the co-channel full duplex mimo system self feed back disturbance restraining method of spatial decomposition, it is characterized in that comprising the following steps:

(1), Received signal strength end self feed back interference matrix H _lIbe expressed as:

Wherein, H _ij∈ C ^{1 × L}represent from co-channel full duplex mimo system jth, 1≤j≤N _rtxroot transmitting antenna to i-th, 1≤i≤N _rrxthe subchannel vector of root reception antenna; N _rtxand N _rrxbe respectively co-channel full duplex mimo system number of transmit antennas and reception antenna number;

Calculate Received signal strength end self feed back interference matrix H _lIorder: R ₁=rank (H _lI), rank is Matrix Calculating order operator; If R ₁< N _rrx, then H _lInon-full rank, enters step (2), otherwise enters step (3);

(2), in co-channel full duplex mimo system signal link, receiving filter is increased: G _rx=I-H _lIh _lI ⁺, wherein H _lI ⁺for matrix H _lImoore-Penrose generalized inverse matrix;

(3), self feed back interference matrix H is held to received signal _lIcarry out singular value decomposition wherein each column element of row vector operates as the matrix-expand of the diagonal element of diagonal matrix by diag () expression successively, () ^hrepresent the conjugate transpose asking matrix; Preferred matrix S ₁, make $0<\mathrm{rank}\left(U_1{S}_1\mathrm{diag}\left(D_1\right)V_1^H\right)<N_{\mathrm{Rrx}};$ Receiving filter is increased in co-channel full duplex mimo system signal link:

$G_{\mathrm{rx}}=I-\left(U_1{S}_1\mathrm{diag}\left(D_1\right)V_1^H\right){\left(U_1{S}_1\mathrm{diag}\left(D_1\right)V_1^H\right)}^{+}$

Wherein, () ⁺represent the Moore-Penrose generalized inverse asking matrix, I representation unit matrix.

Further, further comprising the steps of:

(4), at H _lIduring full rank, continue to design transmitting filter after completing receiving filter design:

Order ${\mathrm{\&Delta;H}}_{\mathrm{LI}}=U_1(I-S_1)\mathrm{diag}\left(D_1\right)V_1^H,$ By Δ H _lIwith P ^-1in conjunction with obtaining Received signal strength end residual interference space matrix:

${\mathrm{\&Delta;H}}_{\mathrm{LI}}{P}^{-1}=\left[\begin{array}{cccc}{\mathrm{\&Delta;H}}_{\mathrm{LI},1}& {\mathrm{\&Delta;H}}_{\mathrm{LI},2}& ...& {\mathrm{\&Delta;H}}_{\mathrm{LI},L}\end{array}\right]$

Wherein, Δ H _{lI, k}, k=1,2 ... L is the residual channel matrix of kth bar multipath, and L is the multipath number of self feed back interference signal time delay equal symbol cycle integral multiple;

Matrix P is:

$P=\left[\begin{array}{c}\mathrm{diag}(Y_1;L)\\ \mathrm{diag}(Y_2;L)\\ ...\\ \mathrm{diag}(Y_L;L)\end{array}\right]$

$Y_i=\left[\begin{array}{ccc}{O}_{1\&times;(i-1)}& 1& O_{1\&times;(L-i)}\end{array}\right]$

Diag (Y in above formula _i; L), 1≤i≤L indicates that L diagonal element is matrix Y _iblock diagonal matrix, O _{1 × n}represent 1 row n, the null matrix of 0≤n≤L-1 row; P ^-1for the inverse matrix of matrix P;

The residual interference space matrix obtaining transmitting terminal is mapped by Received signal strength end residual interference space matrix if non-full rank, increases transmitting filter in co-channel full duplex mimo system signal link:

$G_{\mathrm{tx}}=I-{\left({[\mathrm{\&Delta;}{H}_{\mathrm{LI},1}^T,{\mathrm{\&Delta;H}}_{\mathrm{LI},2}^T...\mathrm{\&Delta;}{H}_{\mathrm{LI},L}^T]}^T\right)}^{+}{[{\mathrm{\&Delta;H}}_{\mathrm{LI},1}^T,{\mathrm{\&Delta;H}}_{\mathrm{LI},2}^T...{\mathrm{\&Delta;H}}_{\mathrm{LI},L}^T]}^T;$

If full rank, is had by singular value decomposition:

${[{\mathrm{\&Delta;H}}_{\mathrm{LI},1}^T,{\mathrm{\&Delta;H}}_{\mathrm{LI},2}^T...{\mathrm{\&Delta;H}}_{\mathrm{LI},L}^T]}^T={\mathrm{\&Delta;U}}_1\mathrm{diag}\left({\mathrm{\&Delta;D}}_1\right){\mathrm{\&Delta;V}}_1^H$

Preferred matrix Δ S ₁make $0<\mathrm{rank}\left({\mathrm{\&Delta;U}}_1\mathrm{diag}\left({\mathrm{\&Delta;D}}_1\right){\mathrm{\&Delta;S}}_1{\mathrm{\&Delta;V}}_1^H\right)<N_{\mathrm{Rtx}},$ Transmitting filter is increased in co-channel full duplex mimo system signal link:

$G_{\mathrm{tx}}=I-{\left({\mathrm{\&Delta;U}}_1\mathrm{diag}\left({\mathrm{\&Delta;D}}_1\right){\mathrm{\&Delta;S}}_1{\mathrm{\&Delta;V}}_1^H\right)}^{+}\left({\mathrm{\&Delta;U}}_1\mathrm{diag}\left({\mathrm{\&Delta;D}}_1\right){\mathrm{\&Delta;S}}_1{\mathrm{\&Delta;V}}_1^H\right).$

Wherein, the matrix S in step (3) ₁diag (D should be able to be offset ₁) in larger one or more diagonal elements corresponding by the base vector that row vector obtains launches the interference in the space that obtains.

Wherein, the matrix Δ S in step (4) ₁diag (Δ D should be able to be offset ₁) in larger one or more diagonal elements corresponding by Δ U ₁the base vector that column vector obtains launches the interference in the space that obtains.

For achieving the above object, the present invention is based on the co-channel full duplex mimo system self feed back disturbance restraining method of spatial decomposition, it is characterized in that comprising the following steps:

(1), Received signal strength end self feed back interference matrix H _lIbe expressed as:

Wherein, H _ij∈ C ^{1 × L}represent from co-channel full duplex mimo system jth, 1≤j≤N _rtxroot transmitting antenna to i-th, 1≤i≤N _rrxthe subchannel vector of root reception antenna; N _rtxand N _rrxbe respectively co-channel full duplex mimo system number of transmit antennas and reception antenna number; H _ij=[h _{ij, 1}, h _{ij, 2}..., h _{ij, L}], wherein h _{ij, k}for row vector H _ijkth column element value, k ∈ (1,2 ..., L), L is the multipath number of self feed back interference signal time delay equal symbol cycle integral multiple;

According to H _lIacquire the channel matrix of kth bar multipath:

$H_{\mathrm{LI},k}=\left(\begin{array}{cccc}{h}_{11,k}& h_{12,k}& ...& h_{1N_{\mathrm{Rtx}},k}\\ h_{21,k}& h_{22,k}& ...& h_{2N_{\mathrm{Rtx}},k}\\ .& .& & .\\ .& .& ...& .\\ .& .& & .\\ h_{N_{\mathrm{Rtx}}1,k}& h_{N_{\mathrm{Rtx}}2,k}& ...& h_{N_{\mathrm{Rtx}}{N}_{\mathrm{Rrx}},k}\end{array}\right)$

Structure sends signal end self feed back interference matrix $H={\left[\begin{array}{cccc}{H}_{\mathrm{LI},1}^T& H_{\mathrm{LI},2}^T& \&CenterDot;\&CenterDot;\&CenterDot;& H_{\mathrm{LI},L-1}^T\end{array}\right]}^T,$ Its order is R ₂=rank (H);

If R ₂< N _rtx, then the non-full rank of H, enters step (2), otherwise enters step (3);

(2), in co-channel full duplex mimo system signal link, transmitting filter G is increased _tx=I-H ⁺h, wherein H ⁺for the Moore-Penrose generalized inverse matrix of matrix H;

(3), singular value decomposition is carried out to transmission signal end self feed back interference matrix H: $H=U_2\mathrm{diag}\left(D_2\right)V_2^H,$ Preferred matrix S ₂, make $0<\mathrm{rank}\left(U_2\mathrm{diag}\left(D_2\right)S_2{V}_2^H\right)<N_{\mathrm{Rtx}};$ Transmitting filter is increased in co-channel full duplex mimo system signal link:

$G_{\mathrm{tx}}=I-{\left(U_2\mathrm{diag}\left(D_2\right)S_2{V}_2^H\right)}^{+}\left(U_2\mathrm{diag}\left(D_2\right)S_2{V}_2^H\right).$

Further, further comprising the steps of:

(4), H full rank time, complete transmitting filter design after continue docking receive filter design:

Order $\mathrm{\&Delta;H}=U_2\mathrm{diag}\left(D_2\right)(I-S_2)V_2^H={[{\mathrm{\&Delta;H}}_1^T,{\mathrm{\&Delta;H}}_2^T...{\mathrm{\&Delta;H}}_L^T]}^T,$ Δ H is the residual interference space sending signal end, is mapped residual interference space Δ H '=[the Δ H obtaining Received signal strength end by Δ H ₁, Δ H ₂Δ H _l];

If the non-full rank of Δ H ', in co-channel full duplex mimo system signal link, increase receiving filter:

G _rx=I-[ΔH ₁,ΔH ₂…ΔH _L][ΔH ₁,ΔH ₂…ΔH _L] ⁺

If Δ H ' full rank, is had by singular value decomposition:

$[{\mathrm{\&Delta;H}}_1,{\mathrm{\&Delta;H}}_2...{\mathrm{\&Delta;H}}_L]={\mathrm{\&Delta;U}}_2\mathrm{diag}\left({\mathrm{\&Delta;D}}_2\right){\mathrm{\&Delta;V}}_2^H;$

Preferred matrix Δ S ₂, make $0<\mathrm{rank}\left({\mathrm{\&Delta;U}}_2{\mathrm{\&Delta;S}}_2\mathrm{diag}\left({\mathrm{\&Delta;D}}_2\right){\mathrm{\&Delta;V}}_2^H\right)<N_{\mathrm{Rrx}},$ Receiving filter is increased in co-channel full duplex mimo system signal link:

$G_{\mathrm{rx}}=I-{\left({\mathrm{\&Delta;U}}_2{\mathrm{\&Delta;S}}_2\mathrm{diag}\left({\mathrm{\&Delta;D}}_2\right){\mathrm{\&Delta;V}}_2^H\right)}^{+}\left({\mathrm{\&Delta;U}}_2{\mathrm{\&Delta;S}}_2\mathrm{diag}\left({\mathrm{\&Delta;D}}_2\right){\mathrm{\&Delta;V}}_2^H\right).$

Wherein, the matrix S in step (3) ₂diag (D should be able to be offset ₂) in larger one or more diagonal elements corresponding by U ₂column vector obtain the interference that base vector launches to obtain in space.

Wherein, the matrix Δ S in step (4) ₂diag (Δ D should be able to be offset ₂) in larger one or more diagonal elements corresponding by the base vector that obtains of row vector launch the interference that obtains in space.。

Goal of the invention of the present invention is achieved in that

The present invention is based on the co-channel full duplex mimo system self feed back disturbance restraining method of spatial decomposition, the signal code cycle is greater than for self feed back channel maximum delay, design sends and receiving filter, it is characterized in that, make transmitting filter and receiving filter matrix be orthogonal to each multipath channel matrix, the transmission namely after design and receiving filter can suppress the self feed back of each multipath to be disturbed.For self feed back channel matrix full rank, design sends and receiving filter, it is characterized in that, self feed back interference space is decomposed into two orthogonal subspaces, first design sends or receiving filter suppress the self feed back interference in a certain subspace after more optionally design to receive or transmitting filter suppresses residual self feed back interference.The dimension that the transmission of the present invention's design and the self feed back that suppresses of receiving filter are disturbed be less than or equal to self feed back interference matrix open into the dimension in space.

The present invention is based on the co-channel full duplex mimo system self feed back disturbance restraining method of spatial decomposition, first, the design of transmitting filter and receiving filter by choose self feed back interference matrix open into the subspace in space and this subspace dimension is less than and even equals its generating space, self feed back interference in this subspace of rear suppression, solves self feed back channel matrix H _lIwith tradition spatial domain Restrainable algorithms not applicable restriction during H full rank.Especially, the method for designing of combining transmitting filter and receiving filter can in matrix H _lIdisturb with suppressing self feed back during H full rank completely.Secondly, consider in the middle of the design of filter by the self feed back channel maximum delay is-greater-than symbol cycle, the electric-wave filter matrix of structure is orthogonal to each multipath channel matrix, orthogonal with above-mentioned subspace matrices, will suppress all multipath self feed back interference in subspace.Visible, the present invention proposes a kind of spatial domain suppressing method having more self feed back interference in the co-channel full duplex mimo system of general significance of application.

Accompanying drawing explanation

Fig. 1 is that in typical co-channel full duplex mimo system, self feed back interference spatial domain suppresses structural representation;

Fig. 2 is the performance schematic diagram of method one in co-channel full duplex mimo system that the co-channel full duplex mimo system self feed back disturbance restraining method that the present invention is based on spatial decomposition proposes;

Fig. 3 is the performance schematic diagram of method two in co-channel full duplex mimo system that the co-channel full duplex mimo system self feed back disturbance restraining method that the present invention is based on spatial decomposition proposes.

Embodiment

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described, so that those skilled in the art understands the present invention better.Requiring particular attention is that, in the following description, when perhaps the detailed description of known function and design can desalinate main contents of the present invention, these are described in and will be left in the basket here.

Embodiment

Fig. 1 is that in typical co-channel full duplex mimo system, self feed back interference spatial domain suppresses structural representation.The self feed back interference spatial domain that the present embodiment adopts suppresses structure consistent with Fig. 1.Scene in this example adopts wireless mobile communications relay station to set up co-channel full duplex mimo system, and parameter is as follows: information source adopts Bernoulli Jacob's binary sequence, and its 0 and 1 probability is all 0.5, sampling period T _s=0.001s; Modulation system adopts BPSK; The number of transmit antennas N of source _stx=3, Space Time Coding speed is 3/4; Source adopts Rayleigh flat channel to co-channel full duplex mimo system channel and adds white Gaussian noise, and signal to noise ratio is expressed as SNR; Co-channel full duplex mimo system receives and number of transmit antennas N _rrx=N _rtx=3; Co-channel full duplex mimo system adopts Decoded-and-Forward mode processing signals, and the process such as decoding when namely doing sky upon receipt of the signals also does the process such as Space Time Coding before transmission signal; System amplifier multiplication factor G=5dB; Self feed back channel adopts flat Rayleigh channel, its fading channel multiple 0dB, maximum multipath number L=3.The present embodiment runs and continues and performance statistics time T=50s.

The co-channel full duplex mimo system self feed back disturbance restraining method that the present invention is based on spatial decomposition proposes two kinds of methods, respectively with transmitting filter and receiving filter for emphasis designs.In the present embodiment, the concrete implementation step based on the co-channel full duplex mimo system self feed back disturbance restraining method one of spatial decomposition comprises:

Step 1: Received signal strength end self feed back interference matrix H _lIbe expressed as:

Received signal strength end self feed back interference matrix H _lIbe co-channel full duplex mimo system feedback interference channel matrix.

Wherein, H _ij∈ C ^{1 × L}represent from co-channel full duplex mimo system jth, 1≤j≤N _rtxroot transmitting antenna to i-th, 1≤i≤N _rrxthe subchannel vector of root reception antenna.N _rtxand N _rrxbe respectively co-channel full duplex mimo system number of transmit antennas and reception antenna number.

Calculate Received signal strength end self feed back interference matrix H _lIorder: R ₁=rank (H _lI), rank is Matrix Calculating order operator; If R ₁< N _rrx, then H _lInon-full rank, enters step 2, otherwise enters step 3.

In the present embodiment, Received signal strength end self feed back interference matrix H _lIby enforcement, personnel build arbitrarily according to system parameters, make its full rank or non-full rank.

Step 2: increase receiving filter in co-channel full duplex mimo system signal link: G _rx=I-H _lIh _lI ⁺, wherein H _lI ⁺for matrix H _lImoore-Penrose generalized inverse matrix.

Adopt this receiving filter, can to self feed back interference channel matrix H _lIin all self feed backs interference suppress completely.

Step 3: hold self feed back interference H to received signal _lIcarry out singular value decomposition wherein each column element of row vector operates as the matrix-expand of the diagonal element of diagonal matrix by diag () expression successively, () ^hrepresent the conjugate transpose asking matrix; Preferred matrix S ₁make $0<\mathrm{rank}\left(U_1{S}_1\mathrm{diag}\left(D_1\right)V_1^H\right)<N_{\mathrm{Rrx}};$

At preferred singular matrix S ₁time, matrix S ₁diag (D should be able to be offset ₁) in larger one or more diagonal elements corresponding by the base vector that row vector obtains launches the interference in the space that obtains.

In the present embodiment, the singular matrix adopted is:

$S_1=\left[\begin{array}{ccc}1& 0& 0\\ 0& 1& 0\\ 0& 0& 0\end{array}\right]$

Receiving filter is increased in co-channel full duplex mimo system signal link:

$G_{\mathrm{rx}}=I-\left(U_1{S}_1\mathrm{diag}\left(D_1\right)V_1^H\right){\left(U_1{S}_1\mathrm{diag}\left(D_1\right)V_1^H\right)}^{+}$

Wherein, () ⁺represent the Moore-Penrose generalized inverse asking matrix, I representation unit matrix.

Adopt this receiving filter, can to self feed back interference channel matrix H _lIin self feed back interference carry out part suppression.

At H _lIduring full rank, suppress if need to carry out the remaining self feed back interference of self feed back AF panel to employing receiving filter, transmitting filter can be set further:

Order by Δ H _lIwith P ^-1in conjunction with obtaining Received signal strength end residual interference space matrix:

${\mathrm{\&Delta;H}}_{\mathrm{LI}}{P}^{-1}=\left[\begin{array}{cccc}{\mathrm{\&Delta;H}}_{\mathrm{LI},1}& {\mathrm{\&Delta;H}}_{\mathrm{LI},2}& ...& {\mathrm{\&Delta;H}}_{\mathrm{LI},L}\end{array}\right]$

Wherein, Δ H _{lI, k}, k=1,2 ... L is the residual channel matrix of kth bar multipath, and L is the multipath number of self feed back interference signal time delay equal symbol cycle integral multiple;

Matrix P is:

$P=\left[\begin{array}{c}\mathrm{diag}(Y_1;L)\\ \mathrm{diag}(Y_2;L)\\ ...\\ \mathrm{diag}(Y_L;L)\end{array}\right]$

$Y_i=\left[\begin{array}{ccc}{O}_{1\&times;(i-1)}& 1& O_{1\&times;(L-i)}\end{array}\right]$

Diag (Y in above formula _i; L), 1≤i≤L indicates that L diagonal element is matrix Y _iblock diagonal matrix, O _{1 × n}represent 1 row n, the null matrix of 0≤n≤L-1 row; P ^-1for the inverse matrix of matrix P;

The residual interference space matrix obtaining transmitting terminal is mapped by Received signal strength end residual interference space matrix if non-full rank, increases transmitting filter in co-channel full duplex mimo system signal link:

$G_{\mathrm{tx}}=I-{\left({[\mathrm{\&Delta;}{H}_{\mathrm{LI},1}^T,{\mathrm{\&Delta;H}}_{\mathrm{LI},2}^T...\mathrm{\&Delta;}{H}_{\mathrm{LI},L}^T]}^T\right)}^{+}{[{\mathrm{\&Delta;H}}_{\mathrm{LI},1}^T,{\mathrm{\&Delta;H}}_{\mathrm{LI},2}^T...{\mathrm{\&Delta;H}}_{\mathrm{LI},L}^T]}^T;$

If full rank, is had by singular value decomposition:

${[{\mathrm{\&Delta;H}}_{\mathrm{LI},1}^T,{\mathrm{\&Delta;H}}_{\mathrm{LI},2}^T...{\mathrm{\&Delta;H}}_{\mathrm{LI},L}^T]}^T={\mathrm{\&Delta;U}}_1\mathrm{diag}\left({\mathrm{\&Delta;D}}_1\right){\mathrm{\&Delta;V}}_1^H$

Preferred matrix Δ S ₁make $0<\mathrm{rank}\left({\mathrm{\&Delta;U}}_1\mathrm{diag}\left({\mathrm{\&Delta;D}}_1\right){\mathrm{\&Delta;S}}_1{\mathrm{\&Delta;V}}_1^H\right)<N_{\mathrm{Rtx}},$ Transmitting filter is increased in co-channel full duplex mimo system signal link:

$G_{\mathrm{tx}}=I-{\left({\mathrm{\&Delta;U}}_1\mathrm{diag}\left({\mathrm{\&Delta;D}}_1\right){\mathrm{\&Delta;S}}_1{\mathrm{\&Delta;V}}_1^H\right)}^{+}\left({\mathrm{\&Delta;U}}_1\mathrm{diag}\left({\mathrm{\&Delta;D}}_1\right){\mathrm{\&Delta;S}}_1{\mathrm{\&Delta;V}}_1^H\right).$

At preferred singular matrix Δ S ₁time, matrix Δ S ₁diag (Δ D should be able to be offset ₁) in larger one or more diagonal elements corresponding by Δ U ₁the base vector that column vector obtains launches the interference in the space that obtains.

Adopt this transmitting filter, can suppress at residue subspace Δ H _lIinterior self feed back interference.

Fig. 2 is the performance schematic diagram of method one in co-channel full duplex mimo system that the co-channel full duplex mimo system self feed back disturbance restraining method that the present invention is based on spatial decomposition proposes.As shown in Figure 2, carry out emulation by the present embodiment and obtain, as Received signal strength end self feed back interference matrix H _lIduring non-full rank, without the error rate of the co-channel full duplex mimo system of self feed back AF panel as shown in curve 21, the receiving filter adopting the present invention to obtain disturbs the error rate that suppresses completely as illustrated by plot 25 to self feed back; As Received signal strength end self feed back interference matrix H _lIduring full rank, without the ber curve of the co-channel full duplex mimo system of self feed back AF panel as shown in curve 22, adopt the present invention only to use the method for receiving filter to disturb the error rate suppressed as shown in curve 23 to part self feed back, adopt the method for conbined usage transmitting filter of the present invention and receiving filter to disturb the error rate suppressed completely as shown in curve 24 to self feed back.Visible, adopt method one proposed by the invention, when self feed back interference matrix full rank and its multidiameter delay are greater than the signal code cycle, part can be made to self feed back interference and suppress, suppress even completely.

In the present embodiment, the concrete implementation step based on the co-channel full duplex mimo system self feed back disturbance restraining method two of spatial decomposition comprises:

Step 1: Received signal strength end self feed back interference matrix H _lIbe expressed as:

Wherein, H _ij∈ C ^{1 × L}represent from co-channel full duplex mimo system jth, 1≤j≤N _rtxroot transmitting antenna to i-th, 1≤i≤N _rrxthe subchannel vector of root reception antenna; N _rtxand N _rrxbe respectively co-channel full duplex mimo system number of transmit antennas and reception antenna number; H _ij=[h _{ij, 1}, h _{ij, 2}..., h _{ij, L}], wherein h _{ij, k}for row vector H _ijkth column element value, k ∈ (1,2 ..., L), L is the multipath number of self feed back interference signal time delay equal symbol cycle integral multiple;

According to H _lIacquire the channel matrix of kth bar multipath:

$H_{\mathrm{LI},k}=\left(\begin{array}{cccc}{h}_{11,k}& h_{12,k}& ...& h_{1N_{\mathrm{Rtx}},k}\\ h_{21,k}& h_{22,k}& ...& h_{2N_{\mathrm{Rtx}},k}\\ .& .& & .\\ .& .& ...& .\\ .& .& & .\\ h_{N_{\mathrm{Rtx}}1,k}& h_{N_{\mathrm{Rtx}}2,k}& ...& h_{N_{\mathrm{Rtx}}{N}_{\mathrm{Rrx}},k}\end{array}\right)$

Structure sends signal end self feed back interference matrix $H={\left[\begin{array}{cccc}{H}_{\mathrm{LI},1}^T& H_{\mathrm{LI},2}^T& \&CenterDot;\&CenterDot;\&CenterDot;& H_{\mathrm{LI},L-1}^T\end{array}\right]}^T,$ Its order is R ₂=rank (H).

If R ₂< N _rtx, then the non-full rank of H, enters step 2, otherwise enters step 3;

Step 2: the transmitting filter of co-channel full duplex mimo system signal link is set to G _tx=I-H ⁺h, wherein H ⁺for the Moore-Penrose generalized inverse matrix of matrix H.

Adopt this transmitting filter, self feed back interference matrix H can be held to received signal _lIall self feed back interference suppress completely.

Step 3: singular value decomposition is carried out to transmission signal end self feed back interference matrix H: $H=U_2\mathrm{diag}\left(D_2\right)V_2^H,$ Preferred matrix S ₂, make $0<\mathrm{rank}\left(U_2\mathrm{diag}\left(D_2\right)S_2{V}_2^H\right)<N_{\mathrm{Rtx}}.$

At preferred singular matrix S ₂time, matrix S ₂diag (D should be able to be offset ₂) in larger one or more diagonal elements corresponding by the base vector that row vector obtains launches the interference in the space that obtains.

In the present embodiment, the singular matrix adopted is:

$S_2=\left[\begin{array}{ccc}0& 0& 0\\ 0& 1& 0\\ 0& 0& 1\end{array}\right]$

The receiving filter of co-channel full duplex mimo system signal link is set to:

$G_{\mathrm{tx}}=I-{\left(U_2\mathrm{diag}\left(D_2\right)S_2{V}_2^H\right)}^{+}\left(U_2\mathrm{diag}\left(D_2\right)S_2{V}_2^H\right).$

Adopt this transmitting filter, self feed back interference matrix H can be held to received signal _lIin self feed back interference carry out part suppression.

When H full rank, suppress if need to carry out the remaining self feed back interference of self feed back AF panel to employing transmitting filter, receiving filter can be set further:

Order $\mathrm{\&Delta;H}=U_2\mathrm{diag}\left(D_2\right)(I-S_2)V_2^H={[{\mathrm{\&Delta;H}}_1^T,{\mathrm{\&Delta;H}}_2^T...{\mathrm{\&Delta;H}}_L^T]}^T,$ Δ H is the residual interference space sending signal end, is mapped residual interference space Δ H '=[the Δ H obtaining Received signal strength end by Δ H ₁, Δ H ₂Δ H _l];

If the non-full rank of Δ H ', in co-channel full duplex mimo system signal link, increase receiving filter:

G _rx=I-[ΔH ₁,ΔH ₂…ΔH _L][ΔH ₁,ΔH ₂…ΔH _L] ⁺

If Δ H ' full rank, is had by singular value decomposition:

$[{\mathrm{\&Delta;H}}_1,{\mathrm{\&Delta;H}}_2...{\mathrm{\&Delta;H}}_L]={\mathrm{\&Delta;U}}_2\mathrm{diag}\left({\mathrm{\&Delta;D}}_2\right){\mathrm{\&Delta;V}}_2^H;$

Preferred matrix Δ S ₂, make $0<\mathrm{rank}\left({\mathrm{\&Delta;U}}_2{\mathrm{\&Delta;S}}_2\mathrm{diag}\left({\mathrm{\&Delta;D}}_2\right){\mathrm{\&Delta;V}}_2^H\right)<N_{\mathrm{Rrx}},$ Receiving filter is increased in co-channel full duplex mimo system signal link:

$G_{\mathrm{rx}}=I-{\left({\mathrm{\&Delta;U}}_2{\mathrm{\&Delta;S}}_2\mathrm{diag}\left({\mathrm{\&Delta;D}}_2\right){\mathrm{\&Delta;V}}_2^H\right)}^{+}\left({\mathrm{\&Delta;U}}_2{\mathrm{\&Delta;S}}_2\mathrm{diag}\left({\mathrm{\&Delta;D}}_2\right){\mathrm{\&Delta;V}}_2^H\right).$

At preferred singular matrix Δ S ₂time, matrix Δ S ₂diag (Δ D should be able to be offset ₂) in larger one or more diagonal elements corresponding by the base vector that obtains of row vector launch the interference that obtains in space.

Fig. 3 is the performance schematic diagram of method two in co-channel full duplex mimo system that the co-channel full duplex mimo system self feed back disturbance restraining method that the present invention is based on spatial decomposition proposes.As shown in Figure 3, carry out emulation by the present embodiment to obtain, when the non-full rank of transmission signal end self feed back interference matrix H, without the error rate of the co-channel full duplex mimo system of self feed back AF panel as shown in curve 32, the present invention is adopted to disturb the error rate suppressed completely as shown in curve 35 to self feed back; When sending signal end self feed back interference matrix H full rank, without the ber curve of the co-channel full duplex mimo system of self feed back AF panel as shown in curve 31, adopt the present invention only to use the method for transmitting filter to disturb the error rate suppressed as shown in curve 34 to part self feed back, adopt the method for conbined usage transmitting filter of the present invention and receiving filter to disturb the error rate suppressed completely as shown in curve 33 to self feed back.Because the non-full rank of receiving filter used, decoding error rate is caused to raise, although so use transmission and receiving filter to suppress self feed back to be disturbed completely, because use receiving filter one to be decided to be non-full order, cause performance on the contrary not as only using transmitting filter.Visible, adopt method one proposed by the invention, when self feed back interference matrix full rank and its multidiameter delay are greater than the signal code cycle, part can be made to self feed back interference and suppress, suppress even completely.

Although be described the illustrative embodiment of the present invention above; so that those skilled in the art understand the present invention; but should be clear; the invention is not restricted to the scope of embodiment; to those skilled in the art; as long as various change to limit and in the spirit and scope of the present invention determined, these changes are apparent, and all innovation and creation utilizing the present invention to conceive are all at the row of protection in appended claim.

Claims (8)

1., based on a co-channel full duplex mimo system self feed back disturbance restraining method for spatial decomposition, it is characterized in that comprising the following steps:

(1), Received signal strength end self feed back interference matrix H _lIbe expressed as:

Wherein, H _ij∈ C ^{1 × L}represent from co-channel full duplex mimo system jth, 1≤j≤N _rtxroot transmitting antenna to i-th, 1≤i≤N _rrxthe subchannel vector of root reception antenna; N _rtxand N _rrxbe respectively co-channel full duplex mimo system number of transmit antennas and reception antenna number; L is the multipath number of self feed back interference signal time delay equal symbol cycle integral multiple;

Calculate Signal reception signal end self feed back interference matrix H _lIorder: R ₁=rank (H _lI), rank is Matrix Calculating order operator; If R ₁< N _rrx, then H _lInon-full rank, enters step (2), otherwise enters step (3);

(2), in co-channel full duplex mimo system signal link, receiving filter is increased: G _rx=I-H _lIh _lI ⁺;

(3), to Signal reception signal end self feed back interference matrix H _lIcarry out singular value decomposition wherein each column element of row vector operates as the matrix-expand of the diagonal element of diagonal matrix by diag () expression successively, () ^hrepresent the conjugate transpose asking matrix; Preferred matrix S ₁, make receiving filter is increased in co-channel full duplex mimo system signal link:

$G_{rx}=I-\left(U_1{S}_{1}diag\right(D_1\left)V_1^H\right){\left(U_1{S}_{1}diag\right(D_1\left)V_1^H\right)}^{+}$

Wherein, () ⁺represent the Moore-Penrose generalized inverse asking matrix, I representation unit matrix.

2. co-channel full duplex mimo system self feed back disturbance restraining method according to claim 1, is characterized in that, further comprising the steps of:

(4), H _lIduring full rank, continue to design transmitting filter after completing receiving filter design:

Order by Δ H _lIwith P ^-1in conjunction with obtaining Received signal strength end residual interference space matrix:

ΔH _LIP ^-1＝[ΔH _LI,1ΔH _LI,2… ΔH _LI,L]

Matrix P is:

$P=\left[\begin{array}{c}diag(Y_1;L)\\ diag(Y_2;L)\\ ...\\ diag(Y_L;L)\end{array}\right]$

Y _i＝[O _1×(i-1)1 O _1×(L-i)]

Diag (Y in above formula _i; L) indicate that L diagonal element is matrix Y _iblock diagonal matrix, the span of i is 1≤i≤L; O _{1 × n}represent 1 row n, the null matrix of 0≤n≤L-1 row;

The residual interference space matrix obtaining transmitting terminal is mapped by Received signal strength end residual interference space matrix if non-full rank, increases transmitting filter in co-channel full duplex mimo system signal link:

$G_{tx}=I-{\left({\&lsqb;{\mathrm{\&Delta;H}}_{LI,1}^T,{\mathrm{\&Delta;H}}_{LI,2}^T...{\mathrm{\&Delta;H}}_{LI,L}^T\&rsqb;}^T\right)}^{+}{\&lsqb;{\mathrm{\&Delta;H}}_{LI,1}^T,{\mathrm{\&Delta;H}}_{LI,2}^T...{\mathrm{\&Delta;H}}_{LI,L}^T\&rsqb;}^T;$

If full rank, is had by singular value decomposition:

${\&lsqb;{\mathrm{\&Delta;H}}_{LI,1}^T,{\mathrm{\&Delta;H}}_{LI,2}^T...{\mathrm{\&Delta;H}}_{LI,L}^T\&rsqb;}^T={\mathrm{\&Delta;U}}_{1}diag\left({\mathrm{\&Delta;D}}_1\right){\mathrm{\&Delta;V}}_1^H$

Preferred matrix Δ S ₁make $0<rank\left({\mathrm{\&Delta;U}}_{1}diag\right({\mathrm{\&Delta;D}}_1\left){\mathrm{\&Delta;S}}_1{\mathrm{\&Delta;V}}_1^H\right)<N_{Rtx},$ Transmitting filter is increased in co-channel full duplex mimo system signal link:

$G_{tx}=I-{\left({\mathrm{\&Delta;U}}_{1}diag\right({\mathrm{\&Delta;D}}_1\left){\mathrm{\&Delta;S}}_1{\mathrm{\&Delta;V}}_1^H\right)}^{+}\left({\mathrm{\&Delta;U}}_{1}diag\right({\mathrm{\&Delta;D}}_1\left){\mathrm{\&Delta;S}}_1{\mathrm{\&Delta;V}}_1^H\right).$

3. co-channel full duplex mimo system self feed back disturbance restraining method according to claim 2, is characterized in that, described matrix Δ S ₁diag (Δ D should be able to be offset ₁) in larger one or more diagonal elements corresponding by Δ U ₁the base vector that column vector obtains launches the interference in the space that obtains.

4., according to the arbitrary described co-channel full duplex mimo system self feed back disturbance restraining method of claims 1 to 3, it is characterized in that, the matrix S in described step (3) ₁diag (D should be able to be offset ₁) in larger one or more diagonal elements corresponding by the base vector that row vector obtains launches the interference in the space that obtains.

5., based on a co-channel full duplex mimo system self feed back disturbance restraining method for spatial decomposition, it is characterized in that comprising the following steps:

(1), Received signal strength end self feed back interference matrix H _lIbe expressed as:

Wherein, H _ij∈ C ^{1 × L}represent from co-channel full duplex mimo system jth, 1≤j≤N _rtxroot transmitting antenna to i-th, 1≤i≤N _rrxthe subchannel vector of root reception antenna; N _rtxand N _rrxbe respectively co-channel full duplex mimo system number of transmit antennas and reception antenna number; L is the multipath number of self feed back interference signal time delay equal symbol cycle integral multiple;

According to H _lIacquire the channel matrix of kth bar multipath:

$H_{LI,k}=\left(\begin{array}{cccc}{h}_{11,k}& h_{12,k}& ...& h_{1N_{Rtx},k}\\ h_{21,k}& h_{22,k}& ...& h_{2N_{Rtx},k}\\ \begin{array}{c}\&CenterDot;\\ \&CenterDot;\\ \&CenterDot;\end{array}& \begin{array}{c}\&CenterDot;\\ \&CenterDot;\\ \&CenterDot;\end{array}& ...& \begin{array}{c}\&CenterDot;\\ \&CenterDot;\\ \&CenterDot;\end{array}\\ h_{N_{Rtx}1,k}& h_{N_{Rtx}2,k}& ...& h_{N_{Rtx}{N}_{Rrx},k}\end{array}\right)$

Wherein h _{ij, k}for H _lIrow vector H _ij=[h _{ij, 1}, h _{ij, 2}..., h _{ij, L}] kth column element value, k ∈ (1,2 ..., L);

Structure sends signal end self feed back interference matrix $H={\left[\begin{array}{cccc}{H}_{LI,1}^T& H_{LI,2}^T& ...& H_{LI,L-1}^T\end{array}\right]}^T,$ Its order is R ₂=rank (H);

If R ₂< N _rtx, then the non-full rank of H, enters step (2), otherwise enters step (3);

(2), in co-channel full duplex mimo system signal link, transmitting filter G is increased _tx=I-H ⁺h;

(3), singular value decomposition is carried out to transmission signal end self feed back interference matrix H: $H=U_{2}diag\left(D_2\right)V_2^H,$ Preferred matrix S ₂, make $0<rank\left(U_{2}diag\right(D_2\left)S_2{V}_2^H\right)<N_{Rtx};$ Transmitting filter is increased in co-channel full duplex mimo system signal link:

$G_{tx}=I-{\left(U_{2}diag\right(D_2\left)S_2{V}_2^H\right)}^{+}\left(U_{2}diag\right(D_2\left)S_2{V}_2^H\right).$

6. co-channel full duplex mimo system self feed back disturbance restraining method according to claim 5, is characterized in that, further comprising the steps of:

(4), H full rank time, complete transmitting filter design after continue docking receive filter design:

Order $\mathrm{\&Delta;}H=U_{2}diag\left(D_2\right)(I-S_2)V_2^H={\&lsqb;{\mathrm{\&Delta;H}}_1^T,{\mathrm{\&Delta;H}}_2^T...{\mathrm{\&Delta;H}}_L^T\&rsqb;}^T,$ Δ H is the residual interference space of transmitting terminal, is mapped residual interference space Δ H '=[the Δ H obtaining Received signal strength end by Δ H ₁, Δ H ₂... Δ H _l];

If the non-full rank of Δ H ', in co-channel full duplex mimo system signal link, increase receiving filter:

G _rx＝I-[ΔH ₁,ΔH ₂...ΔH _L][ΔH ₁,ΔH ₂...ΔH _L] ⁺

If Δ H ' full rank, is had by singular value decomposition:

$\&lsqb;{\mathrm{\&Delta;H}}_1,{\mathrm{\&Delta;H}}_2...{\mathrm{\&Delta;H}}_L\&rsqb;={\mathrm{\&Delta;U}}_{2}diag\left({\mathrm{\&Delta;D}}_2\right){\mathrm{\&Delta;V}}_2^H;$

Preferred matrix Δ S ₂, make $0<rank\left({\mathrm{\&Delta;U}}_2{\mathrm{\&Delta;S}}_{2}diag\right({\mathrm{\&Delta;D}}_2\left){\mathrm{\&Delta;V}}_2^H\right)<N_{Rrx},$ Receiving filter is increased in co-channel full duplex mimo system signal link:

$G_{rx}=I-\left({\mathrm{\&Delta;U}}_2{\mathrm{\&Delta;S}}_{2}diag\right({\mathrm{\&Delta;D}}_2\left){\mathrm{\&Delta;V}}_2^H\right){\left({\mathrm{\&Delta;U}}_2{\mathrm{\&Delta;S}}_{2}diag\right({\mathrm{\&Delta;D}}_2\left){\mathrm{\&Delta;V}}_2^H\right)}^{+}.$

7. co-channel full duplex mimo system self feed back disturbance restraining method according to claim 6, is characterized in that, described matrix Δ S ₂diag (Δ D should be able to be offset ₂) in larger one or more diagonal elements corresponding by the base vector that obtains of row vector launch the interference that obtains in space.

8., according to the arbitrary described co-channel full duplex mimo system self feed back disturbance restraining method of claim 5 to 7, it is characterized in that, the matrix S in described step (3) ₂diag (D should be able to be offset ₂) in larger one or more diagonal elements corresponding by U ₂column vector obtain the interference that base vector launches to obtain in space.