CN104104423A - Method and system for eliminating interference between MIMO relay communication nodes - Google Patents

Abstract

A method for eliminating interference between MIMO relay communication nodes comprises the steps of obtaining a transmitting beam forming vector ti of a relay node Ri and a transmitting beam forming vector tj of a relay node Rj; respectively obtaining a receiving beam forming vector ci of the relay node Ri and a receiving beam forming vector cj of the relay node Rj; obtaining an amplification factor gamma<i> and obtaining an magnification factor gamma<j> of the relay node Rj through the processing by the combination with the receiving beam forming vector cj and the transmitting beam forming vector ti; calculating and obtaining transmitting beam forming signals of a current time slot of the relay node Rj according to the magnification factor gamma<j> , the receiving beam forming vector cj, the transmitting beam forming vector ti and the transmitting beam forming vector tj; calculating and obtaining transmitting beam forming signals of a current time slot of the relay node Ri through the relay node Ri according to the magnification factor gamma<i> , the receiving beam forming vector ci, the transmitting beam forming vector tj and the transmitting beam forming vector ti; and receiving and demodulating the transmitting beam forming signals through a destination node D. According to the method, IRI between the MIMO relay communication nodes can be restrained greatly. The invention further relates to a correlated system.

Description

Removing method and the system between MIMO trunking traffic node, disturbed

Technical field

The present invention relates to removing method and the system between a kind of MIMO trunking traffic node, disturbed.

Background technology

MIMO (Multiple-Input Multiple-Output, multiple-input and multiple-output) system is a core technology that applies to the communication standards such as LTE, WiMAX, WiFi, it allows the multiple antennas multiple spatial flows of sending and receiving simultaneously, and can distinguish and mail to or from the signal in different spaces orientation.

In existing one-way junction technology, the continuous relaying technique of two-way under semiduplex mode can effectively improve spectrum efficiency, thereby becomes a kind of system schema of very attractive.As shown in Figure 1, the typical continuous relay system of two-way comprises a source node S, a destination node D and two fixed relay station R ₁, R ₂, by two via nodes hocket reception and the forwarding of source signal.From the angle of source node, owing to can utilizing two continuous signal transmissions of via node, even thereby destination node exceed the range of signal that it covers, can therefore not cause Transmission yet.

However, still there is a subject matter in the continuous relaying technique of two-way, and the relay well existing in continuous relay processes disturbs (Inter-Relay Interference, IRI) may have influence on the performance of whole system.

Forward in (Decode-and-Forward, DF) relay system in decoding, generally can carry out symbol detection to eliminate IRI at via node.But, in amplification forwarding relay system, carry out IRI and suppress to have more challenge.This be because, in amplification forwarding relay system, the interference of relay well and noise signal tend to be exaggerated, and along with signal sends to destination node together, thereby reduce the Signal to Interference plus Noise Ratio (Signal-to-Interference-and-Noise Ratio, SINR) of system receiver.For suppressing the IRI in amplification forwarding relay system, existing method conventionally adopts part to disturb and eliminates (Partial Interference Cancellation, PIC) (refer to list of references [1]), disturb completely and eliminate (Full Interference Cancellation, FIC) (refer to list of references [2]), successive interference cancellation (Successive Interference Cancellation, SIC) technology such as (refer to list of references [3]) is to strengthen the detectability of signal, wherein, list of references [1] is B.Rankov and A.Wittneben, " Spectral efficient protocols for halfduplex fading relay channels, " IEEE J.Sel.Areas Commun., vol.25, no.2, pp.379-389, Feb.2007, list of references [2] is C.Luo, Y.Gong, and F.Zheng, " Full interference cancellation for two-path relay cooperative networks, " IEEE Trans.Veh.Technol., vol.60, no.1, pp.343-347, Jan.2011, list of references [3] is J.-S.Baek and J.-S.Seo, " Efficient iterative SIC and detection for two-path cooperative block transmission relaying, " IEEE Commun.Lett., vol.16, no.2, pp.199-201, Feb.2012.But these methods are only applicable to the via node of single antenna, can not directly apply to the via node that adopts multi-antenna technology, disturb thereby make still can not to eliminate well relay well in the current amplification forwarding relay system with many antennas.

Summary of the invention

For the deficiencies in the prior art, object of the present invention is intended to provide removing method and the system between the MIMO trunking traffic node of a kind of IRI of inhibition, disturbed.

For achieving the above object, the present invention adopts following technical scheme:

The removing method disturbing between MIMO trunking traffic node, it comprises the following steps:

Steps A: by via node R _iobtain via node R _ilaunching beam figuration vector t _i, and by via node R _jobtain via node R _jlaunching beam figuration vector t _j;

Step B: by via node R _iin conjunction with launching beam figuration vector t _ivia node R is obtained in processing _ireceived beam figuration vector c _i, and by via node R _jin conjunction with launching beam figuration vector t _jvia node R is obtained in processing _jreceived beam figuration vector c _j;

Step C: in conjunction with received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in processing _iamplification coefficient γ _i, and in conjunction with received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in processing _jamplification coefficient γ _j;

Step D: by via node R _jaccording to amplification coefficient γ _j, received beam figuration vector c _j, launching beam figuration vector t _iwith launching beam figuration vector t _jvia node R is obtained in calculating _jthe launching beam figuration signal of current odd number time slot, and launch the launching beam figuration signal of current odd number time slot;

Step e: by via node R _iaccording to amplification coefficient γ _i, received beam figuration vector c _i, launching beam figuration vector t _jwith launching beam figuration vector t _ivia node R is obtained in calculating _ithe launching beam figuration signal of current even number time slot, and send out the launching beam figuration signal of current even number time slot; And

Step F: receive from via node R by destination node D _jor via node R _ilaunching beam figuration signal, and this launching beam figuration signal of demodulation.

Further, steps A is respectively according to following formula I _iwith formula I _jcalculate via node R _iand R _jlaunching beam figuration vector t _iwith launching beam figuration vector t _j; Formula I _ifor formula I _jfor wherein, subscript i and j represent respectively continuous even number time slot and odd number time slot, the i ≠ j that satisfies condition, represent that mould 2 operates, g _irepresent via node R _iand M between destination node D dimension conjugation channel vector, g _jrepresent via node R _jand M between destination node D dimension conjugation channel vector.

Further, step B is according to following formula II _jwith launching beam figuration vector t _jcalculate via node R _jreceived beam figuration vector c _j, and according to following formula II _iwith launching beam figuration vector t _icalculate via node R _ireceived beam figuration vector c _i;

Formula II _ifor wherein, R _ibe the matrix of (M × M) dimension, represent via node R _jto via node R _ibetween channel; represent vectorial t _japposition, and meet rank (T _j)=1; I is the unit matrix of (M × M) dimension; h _irepresent that S is to R _ithe M dimension channel vector sending;

Formula II _jfor wherein, R _jbe the matrix of (M × M) dimension, represent via node R _ito via node R _jbetween channel; represent vectorial t _iapposition, and meet rank (T _i)=1; I is the unit matrix of (M × M) dimension; h _jrepresent that S is to R _jthe M dimension channel vector sending;

The reciprocity of channel satisfies condition system

Further, step C is respectively according to following formula III _iwith formula III _jcalculate amplification coefficient γ _iwith amplification coefficient γ _j, formula III _ifor formula III _jfor ${\mathrm{\&gamma;}}_j=\frac{1}{\sqrt{{\left|c_j^H{h}_j\right|}^2+{\left|c_j^H{R}_j{t}_i\right|}^2+{\left|\right|c_j\left|\right|}^2{\mathrm{\&sigma;}}_{\mathrm{nr}}^2}},i\&NotEqual;j.$

Further, step D specifically comprises following sub-step:

Step D1: by via node R _jaccording to following formula IV, received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in calculating _jthe signal u receiving at a upper odd number time slot _j, this formula IV is wherein, h _jrepresent that source node S is to R _jthe M dimension channel vector sending, variable n _rj(k) represent that variance is m dimension white Gaussian noise vector;

Step D2: by via node R _jthe signal u receiving according to formula V, at a upper odd number time slot _j, amplification coefficient γ _j, received beam figuration vector c _jwith launching beam figuration vector t _icalculate via node R _jthe signal z to be sent of current odd number time slot _j; Formula V is z _j(k)=γ _ju _j(k-1); And

Step D3: by via node R _jby launching beam figuration vector t _jwith signal z to be sent _jbe multiplied by mutually the launching beam figuration signal that forms above-mentioned current odd number time slot, and send out the launching beam figuration signal that deserves front odd number time slot.

Further, step e also comprises following sub-step:

Step e 1: by via node R _iaccording to following formula VI, received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in calculating _ithe signal u receiving at a upper even number time slot _i, this formula VI is wherein, h _irepresent that source node S is to R _ithe M dimension channel vector sending, variable n _ri(k) represent that variance is m dimension white Gaussian noise vector;

Step e 2: by via node R _ithe signal u receiving according to formula VII, at a upper even number time slot _i, amplification coefficient γ _i, received beam figuration vector c _iwith launching beam figuration vector t _jcalculate via node R _ithe signal z to be sent of current even number time slot _i; Formula VII is z _i(k)=γ _iu _i(k-1); And

Step e 3: by via node R _iby launching beam figuration vector t _iwith signal z to be sent _ibe multiplied by mutually the launching beam figuration signal that forms above-mentioned current even number time slot, and send out the launching beam figuration signal that deserves front even number time slot.

The invention still further relates to following technical scheme:

An elimination system of disturbing between MIMO trunking traffic node, it comprises with lower module:

Modules A: by via node R _iobtain via node R _ilaunching beam figuration vector t _i, and by via node R _jobtain via node R _jlaunching beam figuration vector t _j;

Module B: by via node R _iin conjunction with launching beam figuration vector t _ivia node R is obtained in processing _ireceived beam figuration vector c _i, and by via node R _jin conjunction with launching beam figuration vector t _jvia node R is obtained in processing _jreceived beam figuration vector c _j;

Module C: in conjunction with received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in processing _iamplification coefficient γ _i, and in conjunction with received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in processing _jamplification coefficient γ _j;

Module D: by via node R _jaccording to amplification coefficient γ _j, received beam figuration vector c _j, launching beam figuration vector t _iwith launching beam figuration vector t _jvia node R is obtained in calculating _jthe launching beam figuration signal of current odd number time slot, and launch the launching beam figuration signal of current odd number time slot;

Module E: by via node R _iaccording to amplification coefficient γ _i, received beam figuration vector c _i, launching beam figuration vector t _jwith launching beam figuration vector t _ivia node R is obtained in calculating _ithe launching beam figuration signal of current even number time slot, and send out the launching beam figuration signal of current even number time slot; And

Module F: receive from via node R by destination node D _jor via node R _ilaunching beam figuration signal, and this launching beam figuration signal of demodulation.

Further, modules A is respectively according to following formula I _iwith formula I _jcalculate via node R _iand R _jlaunching beam figuration vector t _iwith launching beam figuration vector t _j; Formula I _ifor formula I _jfor wherein, subscript i and j represent respectively continuous even number time slot and odd number time slot, the i ≠ j that satisfies condition, represent that mould 2 operates, g _irepresent via node R _iand M between destination node D dimension conjugation channel vector, g _jrepresent via node R _jand M between destination node D dimension conjugation channel vector.

Further, module B is according to following formula II _jwith launching beam figuration vector t _jcalculate via node R _jreceived beam figuration vector c _j, and according to following formula II _iwith launching beam figuration vector t _icalculate via node R _ireceived beam figuration vector c _i;

Formula II _ifor wherein, R _ibe the matrix of (M × M) dimension, represent via node R _jto via node R _ibetween channel; represent vectorial t _japposition, and meet rank (T _j)=1; I is the unit matrix of (M × M) dimension; h _irepresent that S is to R _ithe M dimension channel vector sending;

Formula II _jfor wherein, R _jbe the matrix of (M × M) dimension, represent via node R _ito via node R _jbetween channel; represent vectorial t _iapposition, and meet rank (T _i)=1; I is the unit matrix of (M × M) dimension; h _jrepresent that S is to R _jthe M dimension channel vector sending;

The reciprocity of channel satisfies condition system

Further, module C is respectively according to following formula III _iwith formula III _jcalculate amplification coefficient γ _iwith amplification coefficient γ _j, formula III _ifor formula III _jfor ${\mathrm{\&gamma;}}_j=\frac{1}{\sqrt{{\left|c_j^H{h}_j\right|}^2+{\left|c_j^H{R}_j{t}_i\right|}^2+{\left|\right|c_j\left|\right|}^2{\mathrm{\&sigma;}}_{\mathrm{nr}}^2}},i\&NotEqual;j.$

Further, module D specifically comprises following submodule:

Module D1: by via node R _jaccording to following formula IV, received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in calculating _jthe signal u receiving at a upper odd number time slot _j, this formula IV is wherein, h _jrepresent that source node S is to R _jthe M dimension channel vector sending, variable n _rj(k) represent that variance is m dimension white Gaussian noise vector;

Module D2: by via node R _jthe signal u receiving according to formula V, at a upper odd number time slot _j, amplification coefficient γ _j, received beam figuration vector c _jwith launching beam figuration vector t _icalculate via node R _jthe signal z to be sent of current odd number time slot _j; Formula V is z _j(k)=γ _ju _j(k-1); And

Module D3: by via node R _jby launching beam figuration vector t _jwith signal z to be sent _jbe multiplied by mutually the launching beam figuration signal that forms above-mentioned current odd number time slot, and send out the launching beam figuration signal that deserves front odd number time slot.

Further, module E also comprises following submodule:

Module E1: by via node R _iaccording to following formula VI, received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in calculating _ithe signal u receiving at a upper even number time slot _i, this formula VI is wherein, h _irepresent that source node S is to R _ithe M dimension channel vector sending, variable n _ri(k) represent that variance is m dimension white Gaussian noise vector;

Module E2: by via node R _ithe signal u receiving according to formula VII, at a upper even number time slot _i, amplification coefficient γ _i, received beam figuration vector c _iwith launching beam figuration vector t _jcalculate via node R _ithe signal z to be sent of current even number time slot _i; Formula VII is z _i(k)=γ _iu _i(k-1); And

Module E3: by via node R _iby launching beam figuration vector t _iwith signal z to be sent _ibe multiplied by mutually the launching beam figuration signal that forms above-mentioned current even number time slot, and send out the launching beam figuration signal that deserves front even number time slot.

Beneficial effect of the present invention is as follows:

The present invention is by building a kind of novel beam form-endowing method based on the undistorted response optimization criterion of minimum variance, make full use of the continuous relay system of two-way spatial domain degree of freedom when signal transmission alternately between continuous slot, approximate SINR on each paths (or time slot) of multipath channel is maximized, thereby obtain above-mentioned wave beam forming vector, relay system uses above-mentioned wave beam forming vector to carry out coherent signal processing, can significantly suppress the internodal IRI of MIMO trunking traffic, thereby effectively improve the bit error rate performance of source node to destination node.Especially, in the time that IRI is comparatively serious, IRI inhibition method proposed by the invention is more more obvious than existing conventional method to the improvement of systematic function.

Brief description of the drawings

Fig. 1 is the continuous relay system schematic diagram of the two-way based on many antenna relays node.

Fig. 2 is the flow chart of the preferred embodiments of the removing method that disturbs between MIMO trunking traffic node of the present invention.

Embodiment

Below in conjunction with accompanying drawing and embodiment, the present invention is described further:

Suppose node R _iand R _jplace is all furnished with M root for launching and the antenna of received beam figuration signal, and wherein M is greater than 2 integer.For simplified model, suppose that source node S and destination node D are furnished with respectively single transmit antenna and single reception antenna." coverage hole " scene is the comparatively typical scene of one in real network, and the signal that exists barrier (as high building etc.) to cause source node S to send due to transmitting procedure can not directly arrive destination node D.In the case, introduce relay system and can effectively solve " coverage hole " problem.Explanation a kind of embodiment of the present invention as an example of " coverage hole " scene example below.

Refer to Fig. 1, the present invention relates to the removing method that disturbs between a kind of MIMO trunking traffic node, its preferred embodiments comprises the following steps:

Steps A: by via node R _iobtain via node R _ilaunching beam figuration vector t _i, and by via node R _jobtain via node R _jlaunching beam figuration vector t _j;

Particularly, respectively according to following formula I _iwith formula I _jcalculate via node R _iand R _jlaunching beam figuration vector t _iwith launching beam figuration vector t _j, can make the received power maximum of destination node D; Wherein, formula I _ifor

${\hat{t}}_i=\frac{g_i}{\left|\right|g_i\left|\right|};$

Formula I _jfor

${\hat{t}}_j=\frac{g_j}{\left|\right|g_j\left|\right|};$

Wherein, subscript i and j represent respectively continuous even number time slot and odd number time slot, the i ≠ j that satisfies condition, represent that mould 2 operates;

G _irepresent via node R _iand M between destination node D dimension conjugation channel vector, g _jrepresent via node R _jand M between destination node D dimension conjugation channel vector.

Step B: in conjunction with launching beam figuration vector t _ivia node R is obtained in processing _ireceived beam figuration vector c _i, and in conjunction with launching beam figuration vector t _jvia node R is obtained in processing _jreceived beam figuration vector c _j;

Particularly, according to following formula II _jwith launching beam figuration vector t _jcalculate via node R _jreceived beam figuration vector c _j, and according to following formula II _iwith launching beam figuration vector t _icalculate via node R _ireceived beam figuration vector c _i; Formula II _ifor

${\hat{c}}_i=\frac{{(R_i{T}_j{R}_i^H+{\mathrm{\&sigma;}}_{\mathrm{nr}}^{2}I)}^{-1}{h}_i}{h_i^H{(R_i{T}_j{R}_i^H+{\mathrm{\&sigma;}}_{\mathrm{nr}}^{2}I)}^{-1}{h}_i};$

Wherein, R _ibe the matrix of (M × M) dimension, represent via node R _jto via node R _ibetween channel; represent vectorial t _japposition, and meet rank (T _j)=1; I is the unit matrix of (M × M) dimension; h _irepresent that S is to R _ithe M dimension channel vector sending;

Formula II _jfor

${\hat{c}}_j=\frac{{(R_j{T}_i{R}_j^H+{\mathrm{\&sigma;}}_{\mathrm{nr}}^{2}I)}^{-1}{h}_j}{h_j^H{(R_j{T}_i{R}_j^H+{\mathrm{\&sigma;}}_{\mathrm{nr}}^{2}I)}^{-1}{h}_j};$

Wherein, R _jbe the matrix of (M × M) dimension, represent via node R _ito via node R _jbetween channel; represent vectorial t _iapposition, and meet rank (T _i)=1; I is the unit matrix of (M × M) dimension; h _jrepresent that S is to R _jthe M dimension channel vector sending;

The reciprocity of channel satisfies condition system

Step C: in conjunction with received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in processing _iamplification coefficient γ _i, and in conjunction with received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in processing _jamplification coefficient γ _j;

Particularly, respectively according to following formula III _iwith formula III _jcalculate amplification coefficient γ _iwith amplification coefficient γ _j, formula III _ifor

${\mathrm{\&gamma;}}_i=\frac{1}{\sqrt{{\left|c_i^H{h}_i\right|}^2+{\left|c_i^H{R}_i{t}_j\right|}^2+{\left|\right|c_i\left|\right|}^2{\mathrm{\&sigma;}}_{\mathrm{nr}}^2}},i\&NotEqual;j;$

Formula III _jfor

${\mathrm{\&gamma;}}_j=\frac{1}{\sqrt{{\left|c_j^H{h}_j\right|}^2+{\left|c_j^H{R}_j{t}_i\right|}^2+{\left|\right|c_j\left|\right|}^2{\mathrm{\&sigma;}}_{\mathrm{nr}}^2}},i\&NotEqual;j.$

Step D: by via node R _jaccording to amplification coefficient γ _j, received beam figuration vector c _j, launching beam figuration vector t _iwith launching beam figuration vector t _jvia node R is obtained in calculating _jthe launching beam figuration signal of current odd number time slot, and launch the launching beam figuration signal of current odd number time slot; This step specifically comprises following sub-step:

Step D1: by via node R _jaccording to following formula IV, received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in calculating _jthe signal u receiving at a upper odd number time slot _j, this formula IV is

Wherein, h _jrepresent that source node S is to R _jthe M dimension channel vector sending, variable n _rj(k) represent that variance is m dimension white Gaussian noise vector.

Step D2: by via node R _jthe signal u receiving according to formula V, at a upper odd number time slot _j, amplification coefficient γ _j, received beam figuration vector c _jwith launching beam figuration vector t _icalculate via node R _jthe signal z to be sent of current odd number time slot _j; Formula V is

Z _j(k)=γ _ju _j(k-1); And

Step D3: by via node R _jby launching beam figuration vector t _jwith signal z to be sent _jbe multiplied by mutually the launching beam figuration signal that forms above-mentioned current odd number time slot, and send out the launching beam figuration signal that deserves front odd number time slot.

Step e: by via node R _iaccording to amplification coefficient γ _i, received beam figuration vector c _i, launching beam figuration vector t _jwith launching beam figuration vector t _ivia node R is obtained in calculating _ithe launching beam figuration signal of current even number time slot, and send out the launching beam figuration signal of current even number time slot.This step also comprises following sub-step:

Step e 1: by via node R _iaccording to following formula VI, received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in calculating _ithe signal u receiving at a upper even number time slot _i, this formula VI is

Wherein, h _irepresent that source node S is to R _ithe M dimension channel vector sending, variable n _ri(k) represent that variance is m dimension white Gaussian noise vector.

Step e 2: by via node R _ithe signal u receiving according to formula VII, at a upper even number time slot _i, amplification coefficient γ _i, received beam figuration vector c _iwith launching beam figuration vector t _jcalculate via node R _ithe signal z to be sent of current even number time slot _i; Formula VII is

z _i(k)＝γ _iu _i(k-1)；

Step e 3: by via node R _iby launching beam figuration vector t _iwith signal z to be sent _ibe multiplied by mutually the launching beam figuration signal that forms above-mentioned current even number time slot, and send out the launching beam figuration signal that deserves front even number time slot; And

Step F: receive from via node R by destination node D _jor via node R _ilaunching beam figuration signal, and this launching beam figuration signal of demodulation.

Below the processing procedure that acquires above-mentioned correlation formula is further described:

Suppose transmitting the symbolic vector s=[s (1) that length is L, s (2) ..., s (L)] ^ttime, channel status remains unchanged, and the average transmission power unit of being normalized to 1, meets E{|s (k) | ²}=1.As shown in Figure 1, via node R _ireceive at even number time slot k the signal that source node S place sends, simultaneously via node R _jthe reception signal of last time slot is forwarded to destination node D.Similarly, via node R _jreceive at odd number time slot (k+1) signal that destination node S place sends, simultaneously via node R _ithe reception signal of last time slot is forwarded to destination node D.Based on the symmetry of this system, without loss of generality, can adopt unified statement, even represent that mould 2 operates.For simplified characterization, below only with via node R _icentered by description object set forth.

Due to source node S and relaying destination node R _jtransmit simultaneously, adopt after wave beam forming receiver R _ithe signal form receiving is as follows:

In above formula, u _i(k) represent via node R _ithe signal receiving after k time slot is by wave beam forming, h _irepresent that source node S is to via node R _ithe M dimension channel vector sending, c _irepresent corresponding via node R _ithe M dimension received beam figuration vector at place.Z in formula (1) _j(k), t _jrepresent respectively via node R _jtransmitted signal and corresponding wave beam forming vector.R _ibe the matrix of (M × M) dimension, represent via node R _jto R _ibetween channel.Meanwhile, the reciprocity of channel satisfies condition system variable n _ri(k) represent that variance is m dimension white Gaussian noise vector.Therefore can obtain the signal y that destination node D place receives _d(k) formula is as follows:

$y_d\left(k\right)=g_j^H{t}_j{z}_j\left(k\right)+n_d\left(k\right)---\left(2\right)$

In formula (2), g _jrepresent via node R _jand M between destination node D dimension conjugation channel vector, n _d(k) represent that destination node D prescription difference is noise.

Can find out from formula (1) and (2), in the continuous relay system of this two-way, each time slot has a via node to be responsible for receiving the signal that source node S place sends, and the signal that another via node was responsible for last time slot to receive is forwarded to D.Because two via nodes are replacing sending and receiving signal always, data communication will keep UNICOM's state always.Because L data symbol of transmission need to take (L+1) individual time slot, now the spectrum efficiency of system is in the time of L > > 1, the performance of this relay communications system is similar to direct communication system, and its spectrum efficiency will move closer to 1.On the other hand, the relaying diversity gain that relay system provides will be conducive to the robustness of raising system transmission.

In amplification forwarding relay system, two signal z that via node sends _i(k), i ∈ { the signal u that 1,2} and last time slot receive _i(k-1) existence function relation, i.e. z between _i(k)=γ _iu _i(k-1), the γ here _irepresent the amplification coefficient of via node.Usually, selection amplification coefficient need ensure the through-put power unit of being normalized to 1 of individual node, i.e. E{|z ₁(k) | ²}=E{|z ₂(k) | ²}=1, therefore has:

${\mathrm{\&gamma;}}_i=\frac{1}{\sqrt{E\left\{{\left|u_i\left(k\right)\right|}^2\right\}}}=\frac{1}{\sqrt{{\left|c_i^H{h}_i\right|}^2+{\left|c_i^H{R}_i{t}_j\right|}^2+{\left|\right|c_i\left|\right|}^2{\mathrm{\&sigma;}}_{\mathrm{nr}}^2}},i,j\&Element;\left\{\mathrm{1,2}\right\},i\&NotEqual;j;---\left(3\right)$

Convolution (1) and (2), known z _j(k), u _i(k-1) between, there is certain association.Accordingly, can derive that to obtain the signal that destination node D receives at each time slot as follows:

$y_d\left(k\right)={\mathrm{\&gamma;}}_i{g}_i^H{t}_i{c}_i^H{h}_{i}s(k-1)+{\mathrm{\&gamma;}}_i{g}_i^H{t}_i{c}_i^H{R}_i{t}_j{z}_j(k-1)+{\mathrm{\&gamma;}}_i{g}_i^H{t}_i{c}_i^H{n}_{\mathrm{ri}}(k-1)+n_d\left(k\right)---\left(4\right)$

In formula (4), the reception signal of destination node D is made up of four part signals, comprises echo signal s (k), noise n _d(k), the represented IRI of second and third part and the diffusion noise from other via nodes in signal.

Two amplification coefficient γ in formula (3) ₁and γ ₂value, jointly determined by wave beam forming vector and channel parameter.Therefore,, before setting the amplification coefficient of via node, should calculate corresponding wave beam forming vector.

According to the transmission formula in formula (4), the assumed average symbol power unit of being normalized to 1, i.e. E{|s (k) | ²}=1, the signal power of two continuous slots is respectively with in like manner, the power of derivation interference signal plus noise signal is also similar, and all units of being normalized to 1 of through-put power that can suppose relay node, meet E{|z _i(k) | ²}=1.Therefore, the SINR of two continuous slots can be calculated as follows:

Formula (5) represents by source node S the SINR to destination node D, and has considered the performance gain that wave beam forming brings.

Therefore,, in many antenna relays system, the average ideal speed in a Frame can reach below will further utilize formula (5) to calculate the relay system capacity that adopts technical scheme of the present invention to reach.

From formula (5), when the noise variance of destination node D during much smaller than echo signal power, satisfy condition time, formula (5) can approximate representation be:

$\mathrm{SINR}\left(k\right)\&ap;\frac{{\left|c_i^H{h}_i\right|}^2}{{\left|c_i^H{R}_i{t}_j\right|}^2+{\left|\right|c_i\left|\right|}^2{\mathrm{\&sigma;}}_{\mathrm{nr}}^2}---\left(6\right)$

Two subscript i, j in formula represent respectively continuous even number time slot and odd number time slot, the i that satisfies condition, j ∈ { 1,2} and i ≠ j.Thus, based on the hypothesis that in a Frame, channel remains unchanged, can change at transmitting terminal wave beam forming vector t the maximization problems of formula (5) _jmaximization problems to formula (6) under the condition remaining unchanged.Be equivalent to the receiving terminal wave beam forming vector c solving under these conditions _ioptimal solution, be expressed as:

$\begin{array}{cc}\min \mathrm{imize}& c_i^H(R_i{t}_j{t}_j^H{R}_i^H+{\mathrm{\&sigma;}}_{\mathrm{nr}}^{2}I)c_i\\ \mathrm{subject\; to}& c_i^H{h}_i=1.\end{array}---\left(7\right)$

In formula, I is the unit matrix of (M × M) dimension.Solve formula (7), can obtain receiving terminal wave beam forming vector c _ianalytic solutions be:

${\hat{c}}_i=\frac{{(R_i{T}_j{R}_i^H+{\mathrm{\&sigma;}}_{\mathrm{nr}}^{2}I)}^{-1}{h}_i}{h_i^H{(R_i{T}_j{R}_i^H+{\mathrm{\&sigma;}}_{\mathrm{nr}}^{2}I)}^{-1}{h}_i},i\&Element;\left\{\mathrm{1,2}\right\}---\left(8\right)$

In formula, represent vectorial t _japposition, and meet rank (T _j)=1.

On the other hand, for making the received power maximum of destination node D, can be by the wave beam forming vector t of transmitting terminal _ibe made as can solve formula (8) based on this formula.Based on the wave beam forming parameter of above-mentioned theory design the IRI that the continuous relay system of two-way is produced is effectively suppressed, thus the overall performance of elevator system significantly.

The present invention is a kind of based on the undistorted response of minimum variance (Minimum Variance Distortionless Response by building, MVDR) the novel beam form-endowing method of Optimality Criteria, make full use of the continuous relay system of two-way spatial domain degree of freedom when signal transmission alternately between continuous slot, approximate SINR on each paths (or time slot) of multipath channel is maximized, thereby obtain above-mentioned wave beam forming vector, relay system uses above-mentioned wave beam forming vector to carry out coherent signal processing, can significantly suppress the IRI between the continuous via node of MIMO two-way, thereby effectively improve bit error rate (the Bit Error Rate of source node to destination node, BER) performance.Especially, in the time that IRI is comparatively serious, method proposed by the invention is more more obvious than existing conventional method to the improvement of systematic function.

The invention still further relates to the elimination system of disturbing between a kind of MIMO trunking traffic node of MIMO trunking traffic node, it comprises with lower module:

Modules A: by via node R _iobtain via node R _ilaunching beam figuration vector t _i, and by via node R _jobtain via node R _jlaunching beam figuration vector t _j;

Module B: in conjunction with launching beam figuration vector t _ivia node R is obtained in processing _ireceived beam figuration vector c _i, and in conjunction with launching beam figuration vector t _jvia node R is obtained in processing _jreceived beam figuration vector c _j;

Module C: in conjunction with received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in processing _iamplification coefficient γ _i, and in conjunction with received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in processing _jamplification coefficient γ _j;

Module D: by via node R _jaccording to amplification coefficient γ _j, received beam figuration vector c _j, launching beam figuration vector t _iwith launching beam figuration vector t _jvia node R is obtained in calculating _jthe launching beam figuration signal of current odd number time slot, and launch the launching beam figuration signal of current odd number time slot; This module specifically comprises following submodule:

Module D1: by via node R _jaccording to following formula IV, received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in calculating _jthe signal u receiving at a upper odd number time slot _j, this formula IV is

Wherein, h _jrepresent that source node S is to R _jthe M dimension channel vector sending, variable n _rj(k) represent that variance is m dimension white Gaussian noise vector.

Module D2: by via node R _jthe signal u receiving according to formula V, at a upper odd number time slot _j, amplification coefficient γ _j, received beam figuration vector c _jwith launching beam figuration vector t _icalculate via node R _jthe signal z to be sent of current odd number time slot _j; Formula V is

Z _j(k)=γ _ju _j(k-1); And

Module D3: by via node R _jby launching beam figuration vector t _jwith signal z to be sent _jbe multiplied by mutually the launching beam figuration signal that forms above-mentioned current odd number time slot, and send out the launching beam figuration signal that deserves front odd number time slot.

Module E: by via node R _iaccording to amplification coefficient γ _i, received beam figuration vector c _i, launching beam figuration vector t _jwith launching beam figuration vector t _ivia node R is obtained in calculating _ithe launching beam figuration signal of current even number time slot, and send out the launching beam figuration signal of current even number time slot.This module also comprises following submodule:

Module E1: by via node R _iaccording to following formula VI, received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in calculating _ithe signal u receiving at a upper even number time slot _i, this formula VI is

Wherein, h _irepresent that source node S is to R _ithe M dimension channel vector sending, variable n _ri(k) represent that variance is m dimension white Gaussian noise vector.

Module E2: by via node R _ithe signal u receiving according to formula VII, at a upper even number time slot _i, amplification coefficient γ _i, received beam figuration vector c _iwith launching beam figuration vector t _jcalculate via node R _ithe signal z to be sent of current even number time slot _i; Formula VII is

z _i(k)＝γ _iu _i(k-1)；

Module E3: by via node R _iby launching beam figuration vector t _iwith signal z to be sent _ibe multiplied by mutually the launching beam figuration signal that forms above-mentioned current even number time slot, and send out the launching beam figuration signal that deserves front even number time slot.And

Module F: receive from via node R by destination node D _jor via node R _ilaunching beam figuration signal, and this launching beam figuration signal of demodulation.

For a person skilled in the art, can be according to technical scheme described above and design, make other various corresponding changes and distortion, and these all changes and distortion all should belong to the protection range of the claims in the present invention within.

Claims (12)

1. the removing method disturbing between MIMO trunking traffic node, is characterized in that: it comprises the following steps:

Steps A: by via node R _iobtain via node R _ilaunching beam figuration vector t _i, and by via node R _jobtain via node R _jlaunching beam figuration vector t _j;

Step B: by via node R _iin conjunction with launching beam figuration vector t _ivia node R is obtained in processing _ireceived beam figuration vector c _i, and by via node R _jin conjunction with launching beam figuration vector t _jvia node R is obtained in processing _jreceived beam figuration vector c _j;

Step C: in conjunction with received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in processing _iamplification coefficient γ _i, and in conjunction with received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in processing _jamplification coefficient γ _j;

Step D: by via node R _jaccording to amplification coefficient γ _j, received beam figuration vector c _j, launching beam figuration vector t _iwith launching beam figuration vector t _jvia node R is obtained in calculating _jthe launching beam figuration signal of current odd number time slot, and launch the launching beam figuration signal of current odd number time slot;

Step e: by via node R _iaccording to amplification coefficient γ _i, received beam figuration vector c _i, launching beam figuration vector t _jwith launching beam figuration vector t _ivia node R is obtained in calculating _ithe launching beam figuration signal of current even number time slot, and send out the launching beam figuration signal of current even number time slot; And

Step F: receive from via node R by destination node D _jor via node R _ilaunching beam figuration signal, and this launching beam figuration signal of demodulation.

2. the removing method disturbing between MIMO trunking traffic node as claimed in claim 1, is characterized in that: steps A is respectively according to following formula I _iwith formula I _jcalculate via node R _iand R _jlaunching beam figuration vector t _iwith launching beam figuration vector t _j; Formula I _ifor formula I _jfor wherein, subscript i and j represent respectively continuous even number time slot and odd number time slot, the i ≠ j that satisfies condition, represent that mould 2 operates, g _irepresent via node R _iand M between destination node D dimension conjugation channel vector, g _jrepresent via node R _jand M between destination node D dimension conjugation channel vector.

3. the removing method disturbing between MIMO trunking traffic node as claimed in claim 2, is characterized in that: step B is according to following formula II _jwith launching beam figuration vector t _jcalculate via node R _jreceived beam figuration vector c _j, and according to following formula II _iwith launching beam figuration vector t _icalculate via node R _ireceived beam figuration vector c _i;

Formula II _ifor wherein, R _ibe the matrix of (M × M) dimension, represent via node R _jto via node R _ibetween channel; represent vectorial t _japposition, and meet rank (T _j)=1; I is the unit matrix of (M × M) dimension; h _irepresent that S is to R _ithe M dimension channel vector sending; Formula II _jfor wherein, R _jbe the matrix of (M × M) dimension, represent via node R _ito via node R _jbetween channel; represent vectorial t _iapposition, and meet rank (T _i)=1; I is the unit matrix of (M × M) dimension; h _jrepresent that S is to R _jthe M dimension channel vector sending;

The reciprocity of channel satisfies condition system

4. the removing method disturbing between MIMO trunking traffic node as claimed in claim 3, is characterized in that: step C is respectively according to following formula III _iwith formula III _jcalculate amplification coefficient γ _iwith amplification coefficient γ _j, formula III _ifor formula III _jfor ${\mathrm{\&gamma;}}_j=\frac{1}{\sqrt{{\left|c_j^H{h}_j\right|}^2+{\left|c_j^H{R}_j{t}_i\right|}^2+{\left|\right|c_j\left|\right|}^2{\mathrm{\&sigma;}}_{\mathrm{nr}}^2}},i\&NotEqual;j.$

5. the removing method disturbing between MIMO trunking traffic node as claimed in claim 4, is characterized in that: step D specifically comprises following sub-step:

Step D1: by via node R _jaccording to following formula IV, received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in calculating _jthe signal u receiving at a upper odd number time slot _j, this formula IV is wherein, h _jrepresent that source node S is to R _jthe M dimension channel vector sending, variable n _rj(k) represent that variance is m dimension white Gaussian noise vector;

Step D2: by via node R _jthe signal u receiving according to formula V, at a upper odd number time slot _j, amplification coefficient γ _j, received beam figuration vector c _jwith launching beam figuration vector t _icalculate via node R _jthe signal z to be sent of current odd number time slot _j; Formula V is z _j(k)=γ _ju _j(k-1); And

Step D3: by via node R _jby launching beam figuration vector t _jwith signal z to be sent _jbe multiplied by mutually the launching beam figuration signal that forms above-mentioned current odd number time slot, and send out the launching beam figuration signal that deserves front odd number time slot.

6. the removing method disturbing between MIMO trunking traffic node as claimed in claim 5, is characterized in that: step e also comprises following sub-step:

Step e 1: by via node R _iaccording to following formula VI, received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in calculating _ithe signal u receiving at a upper even number time slot _i, this formula VI is wherein, h _irepresent that source node S is to R _ithe M dimension channel vector sending, variable n _ri(k) represent that variance is m dimension white Gaussian noise vector;

Step e 2: by via node R _ithe signal u receiving according to formula VII, at a upper even number time slot _i, amplification coefficient γ _i, received beam figuration vector c _iwith launching beam figuration vector t _jcalculate via node R _ithe signal z to be sent of current even number time slot _i; Formula VII is z _i(k)=γ _iu _i(k-1); And

Step e 3: by via node R _iby launching beam figuration vector t _iwith signal z to be sent _ibe multiplied by mutually the launching beam figuration signal that forms above-mentioned current even number time slot, and send out the launching beam figuration signal that deserves front even number time slot.

7. an elimination system of disturbing between MIMO trunking traffic node, is characterized in that: it comprises with lower module:

Modules A: by via node R _iobtain via node R _ilaunching beam figuration vector t _i, and by via node R _jobtain via node R _jlaunching beam figuration vector t _j;

Module B: by via node R _iin conjunction with launching beam figuration vector t _ivia node R is obtained in processing _ireceived beam figuration vector c _i, and by via node R _jin conjunction with launching beam figuration vector t _jvia node R is obtained in processing _jreceived beam figuration vector c _j; Module C: in conjunction with received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in processing _iamplification coefficient γ _i, and in conjunction with received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in processing _jamplification coefficient γ _j;

Module D: by via node R _jaccording to amplification coefficient γ _j, received beam figuration vector c _j, launching beam figuration vector t _iwith launching beam figuration vector t _jvia node R is obtained in calculating _jthe launching beam figuration signal of current odd number time slot, and launch the launching beam figuration signal of current odd number time slot;

Module E: by via node R _iaccording to amplification coefficient γ _i, received beam figuration vector c _i, launching beam figuration vector t _jwith launching beam figuration vector t _ivia node R is obtained in calculating _ithe launching beam figuration signal of current even number time slot, and send out the launching beam figuration signal of current even number time slot; And

Module F: receive from via node R by destination node D _jor via node R _ilaunching beam figuration signal, and this launching beam figuration signal of demodulation.

8. the elimination system of disturbing between MIMO trunking traffic node as claimed in claim 7, is characterized in that: modules A is respectively according to following formula I _iwith formula I _jcalculate via node R _iand R _jlaunching beam figuration vector t _iwith launching beam figuration vector t _j; Formula I _ifor formula I _jfor wherein, subscript i and j represent respectively continuous even number time slot and odd number time slot, the i ≠ j that satisfies condition, represent that mould 2 operates; g _irepresent via node R _iand M between destination node D dimension conjugation channel vector, g _jrepresent via node R _jand M between destination node D dimension conjugation channel vector.

9. the elimination system of disturbing between MIMO trunking traffic node as claimed in claim 8, is characterized in that: module B is according to following formula II _jwith launching beam figuration vector t _jcalculate via node R _jreceived beam figuration vector c _j, and according to following formula II _iwith launching beam figuration vector t _icalculate via node R _ireceived beam figuration vector c _i;

Formula II _ifor wherein, R _ibe the matrix of (M × M) dimension, represent via node R _jto via node R _ibetween channel; represent vectorial t _japposition, and meet rank (T _j)=1; I is the unit matrix of (M × M) dimension; h _irepresent that S is to R _ithe M dimension channel vector sending; Formula II _jfor wherein, R _jbe the matrix of (M × M) dimension, represent via node R _ito via node R _jbetween channel; represent vectorial t _iapposition, and meet rank (T _i)=1; I is the unit matrix of (M × M) dimension; h _jrepresent that S is to R _jthe M dimension channel vector sending;

The reciprocity of channel satisfies condition system

10. the elimination system of disturbing between MIMO trunking traffic node as claimed in claim 9, is characterized in that: module C is respectively according to following formula III _iwith formula III _jcalculate amplification coefficient γ _iwith amplification coefficient γ _j, formula III _ifor formula III _jfor ${\mathrm{\&gamma;}}_j=\frac{1}{\sqrt{{\left|c_j^H{h}_j\right|}^2+{\left|c_j^H{R}_j{t}_i\right|}^2+{\left|\right|c_j\left|\right|}^2{\mathrm{\&sigma;}}_{\mathrm{nr}}^2}},i\&NotEqual;j.$

The elimination system of disturbing between 11. MIMO trunking traffic nodes as claimed in claim 10, is characterized in that: module D specifically comprises following submodule:

Module D1: by via node R _jaccording to following formula IV, received beam figuration vector c _jwith launching beam figuration vector t _ivia node R is obtained in calculating _jthe signal u receiving at a upper odd number time slot _j, this formula IV is wherein, h _jrepresent that source node S is to R _jthe M dimension channel vector sending, variable n _rj(k) represent that variance is m dimension white Gaussian noise vector;

Module D2: by via node R _jthe signal u receiving according to formula V, at a upper odd number time slot _j, amplification coefficient γ _j, received beam figuration vector c _jwith launching beam figuration vector t _icalculate via node R _jthe signal z to be sent of current odd number time slot _j; Formula V is z _j(k)=γ _ju _j(k-1); And

Module D3: by via node R _jby launching beam figuration vector t _jwith signal z to be sent _jbe multiplied by mutually the launching beam figuration signal that forms above-mentioned current odd number time slot, and send out the launching beam figuration signal that deserves front odd number time slot.

The elimination system of disturbing between 12. MIMO trunking traffic nodes as claimed in claim 11, is characterized in that: module E also comprises following submodule:

Module E1: by via node R _iaccording to following formula VI, received beam figuration vector c _iwith launching beam figuration vector t _jvia node R is obtained in calculating _ithe signal u receiving at a upper even number time slot _i, this formula VI is wherein, h _irepresent that source node S is to R _ithe M dimension channel vector sending, variable n _ri(k) represent that variance is m dimension white Gaussian noise vector;

Module E2: by via node R _ithe signal u receiving according to formula VII, at a upper even number time slot _i, amplification coefficient γ _i, received beam figuration vector c _iwith launching beam figuration vector t _jcalculate via node R _ithe signal z to be sent of current even number time slot _i; Formula VII is z _i(k)=γ _iu _i(k-1); And

Module E3: by via node R _iby launching beam figuration vector t _iwith signal z to be sent _ibe multiplied by mutually the launching beam figuration signal that forms above-mentioned current even number time slot, and send out the launching beam figuration signal that deserves front even number time slot.