CN102130750B - Signal transmission method and device - Google Patents

Abstract

The embodiment of the invention provides a signal transmission method and a signal transmission device. The method mainly comprises the following steps of: performing relay filtering processing to divide a hybrid channel, connected to a plurality of users by the relay station, of a plurality of base stations into a plurality of independent channels, connected to the single users by the relay station, of the single base stations by using the relay station; and performing pre-coding processing on base station sides and performing the relay filtering processing on a relay station side to divide each independent channel into a plurality of sub-channels, connected to the single users by the relay station, of the single base stations, wherein each sub-channel corresponds to a data stream in data from the single base station to the single user. By the signal transmission method and the signal transmission device, inter-cell interference in a cooperative network can be effectively suppressed, the degree of freedom of a system is increased and system capacity is increased.

Description

Method for transmitting signals and device

Technical field

The present invention relates to communication technical field, relate in particular to method for transmitting signals and device in a kind of collaborative network.

Background technology

IMT-Advanced (International Mobile Telecommnications-Advanced, IMT-Advanced) objectives for the target up to 100Mbps～1Gbps peak data rate is provided in the bandwidth of 20～100MHz, are more than 10 times of HSDPA (High SpeedDownlink Package Access) at least.But, for adopting OFDM (Orthogonal Frequency Division Multiplexing, orthogonal frequency division multiplexi) the IMT-Advanced system of technology, the mechanism that self there is no the presence of intercell interference inhibition due to its physical-layer techniques, if the multiplexing factor of proportion is 1, can cause the interference level of minizone to increase, the performance that particularly is positioned at Cell Edge User can be subject to very big loss.Therefore, presence of intercell interference has just become the main interference source in the IMT-Advanced mobile communication system.For improving the data rate of cell edge, guarantee the seamless service support to the user, improve the availability of frequency spectrum of system, must effectively alleviate presence of intercell interference.

In order to solve problem of inter-cell interference, in the collaborative network structure, by cooperating of relay station and each base station, realize effective transmission of user data.At first relay station will be separated into from the signal of many base stations each signal that sends the base station, then the signal that each sends the base station will be transmitted to the user of each residential quarter.

In realizing process of the present invention, the inventor finds the scheme of above-mentioned collaborative network structure of the prior art, and there are the following problems at least: can interference-free receive the signal from respective base station although this scheme can be guaranteed each user effectively, between a plurality of data flow of each user after but signal separates, power division is not good, so the power system capacity performance is lower.

Summary of the invention

Embodiments of the invention provide a kind of method for transmitting signals and device, to realize suppressing presence of intercell interference, improve power system capacity.

A kind of method for transmitting signals comprises:

Relay station in collaborative network is processed by relaying filtering, and the mixed channel that a plurality of base stations are connected to a plurality of users by described relay station is decomposed into a plurality of single base stations and is connected to the independent channel at alone family by described relay station;

Process by the precoding processing of base station side and the relaying filtering of relay station side, each described independent channel is resolved into a plurality of single base stations be connected to the subchannel at alone family by described relay station, each described subchannel corresponding described single base station data flow in the data at described alone family.

A kind of signal transmitting apparatus is arranged in relay station, comprising:

The first channel decomposing module is used for processing by relaying filtering, and the mixed channel that a plurality of base stations are connected to a plurality of users by described relay station is decomposed into a plurality of single base stations and is connected to the independent channel at alone family by described relay station;

The second channel decomposing module, be used for by base station pre-coding matrix and relaying filtering matrix, each described independent channel is resolved into a plurality of single base stations be connected to the subchannel at alone family by described relay station, each described subchannel corresponding described single base station data flow in the data at described alone family.

Can be found out by the technical scheme that the embodiment of the invention described above provides, the embodiment of the present invention has resolved into many base stations-single relaying-multi-user's mixed channel the independent channel at a plurality of single base stations-single relaying-alone family, and each independent channel after decomposing further resolves into a plurality of parallel data flow.Thereby effectively suppress presence of intercell interference, increased the degree of freedom of system, improve power system capacity.

Description of drawings

In order to be illustrated more clearly in the technical scheme of the embodiment of the present invention, during the below will describe embodiment, the accompanying drawing of required use is done to introduce simply, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the collaborative network structural representation based on the shared relaying of many antennas in the embodiment of the present invention;

Fig. 2 is the process chart of a kind of method for transmitting signals of the embodiment of the present invention one proposition;

Fig. 3 is the process chart of the channel decomposing method in collaborative network framework under a kind of AF pattern of proposing of the embodiment of the present invention one;

Fig. 4 is the process chart of the channel decomposing method in collaborative network framework under a kind of DF pattern of proposing of the embodiment of the present invention one;

Fig. 5 is that the described scheme of a kind of embodiment of the present invention and " ZF scheme " of the prior art and " non-relay interference inhibition " scheme have been carried out the simulation result schematic diagram of numerical simulation;

Fig. 6 is that the described scheme of the another kind of embodiment of the present invention and " ZF scheme " of the prior art and " non-relay interference inhibition " scheme have been carried out the simulation result schematic diagram of numerical simulation;

The specific implementation structure chart of a kind of side signal transmission subtraction unit that Fig. 7 provides for the embodiment of the present invention.

Embodiment

For ease of the understanding to the embodiment of the present invention, be further explained explanation below in conjunction with accompanying drawing as an example of several specific embodiments example, and each embodiment does not consist of the restriction to the embodiment of the present invention.

Embodiment one

As shown in Figure 1, for share the collaborative network structure of relaying based on many antennas.In this collaborative network structure, by cooperating of relay station and each base station, realize effective transmission of user data.In Fig. 1, relay station is positioned at the intersection of three neighbor cells, and the base station of three residential quarters communicates with the user at edge separately by described relay station.

The handling process of a kind of method for transmitting signals that the present embodiment provides comprises following treatment step as shown in Figure 2:

Step 21, process by relaying filtering, will resolve into the independent channel at a plurality of " single base station-single relaying-alone families " for the mixed channel of " many base stations-single relaying-multi-user " of a plurality of base stations.

Relay station in collaborative network is processed by relaying filtering, a plurality of base stations are connected to the mixed channel of a plurality of users (being many base stations-single relaying-multi-user) by described relay station, be decomposed into a plurality of parallel single base stations and be connected to the independent channel of alone family (being single base station-single relaying-alone family) by described relay station, the corresponding described single base station of each described independent channel is transferred to the data at described alone family by relay station, the respectively corresponding user of each described parallel independent channel.

Above-mentioned processing procedure is the first heavy channel decomposing process.

Step 22, process by precoding processing and relaying filtering, above-mentioned each independent channel is resolved into a plurality of subchannels, data flow of each subchannel transmission.

Process by the precoding processing of base station side and the relaying filtering of relay station side, each described independent channel is resolved into a plurality of single base stations be connected to the parallel subchannel at alone family by described relay station, each described subchannel corresponding described single base station data flow in the data at described alone family.

Above-mentioned processing procedure is the second heavy channel decomposing process.

This embodiment has resolved into many base stations-single relaying-multi-user's mixed channel the independent channel at a plurality of single base stations-single relaying-alone family by double channel decomposing process, and each independent channel after decomposing further resolves into a plurality of subchannels.Thereby increased the degree of freedom of system, created prerequisite for further improving the power system capacity performance.

Embodiment two

At first this embodiment describes the first heavy channel decomposing process of many base station-relay stations-user.This first heavy channel decomposing process is applicable to AF (Amplify and Forward, amplification forwarding) pattern in ofdm system and the collaborative network framework under DF (Decode and Forward, decoding forwards) pattern.

For the AF pattern, the handling process of the channel decomposing method in a kind of collaborative network framework that this embodiment scheme proposes comprises the steps: as shown in Figure 3

Step 31, the backward filtering matrix by setting in advance decompose the mixed channel of many base stations to relay station, obtain the signal that each base station sends to relay station.

In this embodiment, hypothesis base station and number of users are L, and antenna number is M, and the antenna number of relay station is N, and N 〉=LM is arranged.Carry out the first heavy channel decomposing in many base stations to the first hop channel of relay station, by the backward filtering matrix that sets in advance, the parallel independent channel that relay station is arrived in a plurality of single base stations has been resolved into to the mixed channel of relay station in many base stations.By this parallel independent channel, obtain the signal that each base station sends to relay station.

Above-mentioned backward filtering matrix need to arrange respectively for each base station, such as, for I base station, backward filtering matrix A is set _l

The signal that each base station sends is through after wireless channel, and the place superposes and received by relay station at relay station.In order to isolate the data of I base station from mixed signal, at first relay station multiply by mixed signal above-mentioned backward filtering matrix A _lThrough above-mentioned backward filtering matrix A _lSignal after processing is the data of I base station, can be expressed as:

Wherein, y represents the mixed signal of many base stations that relay station receives; H _lRepresent the channel matrix between I base station and relay station; F _lThe encoder matrix that represents I base station; s _lThe transmitting data that represents I base station; n ₁The expression additive white Gaussian noise.

By above-mentioned formula (1) as can be known, in order to guarantee x _l' only comprise the transmitted signal of I base station, backward filtering matrix A _lMust satisfy:

A _l＝arg({A _lH _i＝0|i＝1，...，L，i≠l}) (2)

For finding the solution the matrix A that satisfies above-mentioned formula (2) _l, structural matrix [H _l]=[H ₁..., H _l-1, H _l+1..., H _L], and to [H _l] carry out SVD (Singular Value Decomposition, singular value decomposition).SVD is decomposed into Arbitrary Matrix the product of an orthogonal matrix, a diagonal matrix and an orthogonal matrix, to [H _l] SVD can be expressed as:

Wherein, With

Be called [H _l] carry out left matrix and the right matrix of SVD; Be a diagonal matrix, the element on its diagonal is called matrix [H _l] singular value; ∑ _HExpression

The submatrix of middle diagonal element non-zero; With

Represent the vector corresponding with the non-zero singular value; U _{H, l}And V _{H, l}The vector that expression is corresponding with zero singular value.

Wherein, subscript ^HExpression transpose conjugate matrix, U _{H, l}Matrix for N-M (L-1) * N dimension.Make A _l=U _{H, l}Due to U _{H, l}Orthogonal matrix, so A _lSatisfy above-mentioned formula (2), so far, above-mentioned formula (1) can be reduced to:

${x_l}^{\′}=\sqrt{\mathrm{\η}}{A}_l{H}_l{F}_l{s}_l+A_l{n}_1---\left(4\right)$

By above-mentioned formula (4) as seen, through backward filtering matrix A _lThe mixed signal of processing only comprises the signal of I base station.Travel through all values by I in formula (4), just the parallel independent channel that relay station is arrived in a plurality of single base stations has been resolved into to the mixed channel of relay station in many base stations.

Step 32, by relay process matrix and forward direction filtering matrix, each base station is decomposed to the signal that relay station sends, obtain the signal that each base station sends to each user.

, obtain the parallel independent channel of a plurality of single base stations to relay station, then passing through the processing of relay process matrix and forward direction filtering matrix to the second hop channel of multi-user at relay station, further obtaining the signal that each base station sends to each user.

Above-mentioned relay process matrix and forward direction filtering matrix need to arrange respectively for each user, such as, for I user, relay process matrix X is set _lWith forward direction filtering matrix B _l

Relay station passes through backward filtering matrix A to the mixed signal that receives _lAfter carrying out backward filtering, with the backward filtering signal x that obtains _l' multiply by relay process matrix X _l, then the signal times after processing is with forward direction filtering matrix B _l, pass through again at last amplification coefficient Carry out amplification forwarding.Therefore, the signal from I base station that receives of I user can be expressed as:

Wherein, G _IExpression is relayed to I user's channel matrix; n _{2, I}The expression additive white Gaussian noise.

For guaranteeing above-mentioned r _l′Only comprise the transmitted signal of I base station, above-mentioned forward direction filtering matrix B _lNeed to satisfy:

B _l＝arg({G _iB _l＝0|i＝1，...，L，i≠l}) (6)

In like manner, for solution matrix B _l, consider structural matrix

And to [G _l] carry out SVD and get:

Wherein,

With

Expression is to [G _l] carry out left matrix and the right matrix of SVD gained;

Expression is to [G _l] carrying out the diagonal matrix of SVD gained, the element on its diagonal is called matrix [G _l] singular value; ∑ _GExpression

The submatrix of middle diagonal element non-zero; With Represent the vector corresponding with the non-zero singular value; U _{G, l}And V _{G, l}The vector that expression is corresponding with zero singular value.Wherein, V _{G, l}Matrix for N * N-M (L-1) dimension.Make B _l=V _{G, l}, B _lSatisfy above-mentioned formula (5).

Thus, with the above-mentioned formula of above-mentioned formula (4) formula substitution (5), and make I '=I, W _l=B _lX _lA _l, abbreviation can get:

Wherein, matrix W _lBe the filtering matrix of relay station.

Handling process through above-described embodiment, mixed channel for " many base stations-single relaying-multi-user " of a plurality of base stations can have been resolved into the parallel independent channel at many " single base station-single relaying-alone families ", the respectively corresponding user of each parallel independent channel.Above-mentioned parallel independent channel is mimo channel.

For the DF pattern, the handling process of the channel decomposing method in a kind of collaborative network framework that the present invention proposes comprises the steps: as shown in Figure 4

Step 41, the backward filtering matrix by setting in advance decompose the mixed channel of many base stations to relay station, obtain the signal that each base station sends to relay station.

For the first heavy channel decomposing, the DF pattern takes the mode identical with the AF pattern to carry out forward direction filtering and backward filtering, thereby obtains L bar base station-relay station-user's parallel independent channel.Detailed process is as follows:

At first consider many base stations to the first hop channel of relay station, at first relay station will receive signal times with backward filtering matrix A after receiving multiple base station signal _l, to isolate the transmitted signal of I base station.Backward filtered signal can be expressed as:

By (9) formula as can be known, in order to guarantee x _l' only comprise the transmitted signal of I base station, backward filtering matrix A _lMust satisfy:

A _l＝arg({A _lH _i＝0|i＝1，..，L，i≠l}) (10)

The matrix A of satisfied for finding the solution (10) formula _l, need structural matrix [H _l]=[H ₁..., H _l-1, H _l+1..., H _L], and to [H _l] carry out SVD and get:

Wherein, subscript ^HExpression transpose conjugate matrix, U _{H, l}Matrix for N-M (L-1) * N dimension.Make A _l=U _{H, l}, A _lSatisfy (10) formula.(9) formula can be reduced to thus:

${x_l}^{\′}=\sqrt{\mathrm{\η}}{A}_l{H}_l{F}_l{s}_l+A_l{n}_1---\left(12\right)$

By (12) formula as seen, through backward filtering matrix A _l, a plurality of single base stations have been resolved into to the parallel independent channel of relay station to the mixed channel of relay station in many base stations.

Step 42, by the forward direction filtering matrix, each base station is decomposed to the signal that relay station sends, obtain the signal that each base station sends to each user.

Consider that now relay station is to the second hop channel of multi-user.After relay station carries out backward filtering to received signal, at first carry out DF decoding and remove noise, then with decoded signal times with forward direction filtering matrix B _l, with power M η/N, filtered signal is sent to the user at last.Therefore, I user's reception signal can be expressed as:

Similar with the analytical method of the first hop channel, for guaranteeing r _lOnly comprise the transmitted signal of I base station, forward direction filtering matrix B _lNeed to satisfy:

B _l＝arg({G _iB _l＝0|i＝1，...，L，i≠l}) (14)

In like manner, structural matrix

And to [G _l] carry out SVD and get:

Wherein, V _{G, l}Matrix for N * N-M (L-1) dimension.Make B _l=V _{G, l}, B _lSatisfy (14) formula.Thus (13) but the formula abbreviation be:

$r_l=\sqrt{\frac{\mathrm{M\η}}{N}}{G}_l{B}_l{X}_l{s}_l+n_{2,l}---\left(16\right)$

By (12) formula and (16) formula as seen, by A _l, X _lAnd B _lThe relaying filtering matrix that forms has resolved into the mixed channel of " many base stations-single relaying-multi-user " the parallel independent channel at L bar " single base station-single relaying-alone family ".

This embodiment is applicable to AF in ofdm system and the collaborative network framework under the DF pattern.Transmission end of base station carries out precoding by pre-coding matrix to transmitting data, carrying out filtering at the relay station receiving terminal by the relaying filtering matrix processes, the user's of correspondence that above-described embodiment one is obtained a parallel independent channel further resolves into a plurality of parallel subchannels, and each subchannel is corresponding to user's a data flow.Above-mentioned pre-coding matrix obtains according to channel matrix usually, and the product that makes pre-coding matrix, channel matrix and relaying filtering matrix three is diagonal matrix.

Above-mentioned pre-coding matrix and relaying filtering matrix need to arrange respectively for each base station, such as, for I base station, base station pre-coding matrix F is set _lWith relaying filtering matrix W _lBelow design relaying filtering matrix W from the angle that maximizes end-to-end capacity _l

For the AF pattern:

For the user's of correspondence of above-mentioned I base station the parallel independent channel of I bar,

Make Q _l=G _lW _l, S _l=F _ls _l, the capacity of above-mentioned l bar independent channel is:

To Q _lAnd H _lCarry out SVD: $Q_l=U_{Q_l}{\mathrm{\Σ}}_{Q_l}{V}_{Q_l}^H,H_l=U_{H_l}{\mathrm{\Σ}}_{H_l}{V}_{H_l}^H,$ With the above-mentioned formula of substitution as a result (17), and abbreviation can get:

Wherein,

Representing matrix Q _lQ _l ^HCharacteristic value,

Representing matrix H _lH _l ^HCharacteristic value, and diag represents diagonal matrix.

Theoretical proof as can be known, when $U_{Q_l}=U_{G_l}$ And $V_{Q_l}=U_{H_l}$

For to matrix G _lCarry out the orthogonal matrix after SVD: $G_l=U_{G_l}{\mathrm{\Σ}}_{G_l}{V}_{G_l}^H$ ) time, channel capacity C _lMaximum.Have this moment $Q_l=U_{G_l}{\mathrm{\Σ}}_{Q_l}{U}_{H_l}^H,$ And formula (18) is reduced to:

Due to Q _l=G _lW _l, therefore have:

$G_l{W}_l=U_{G_l}{\mathrm{\Σ}}_{Q_l}{U}_{H_l}^H---\left(20\right)$

For satisfying above-mentioned formula (20), order $W_l=V_{G_l}{U}_{H_l}^H,$ Have:

Than formula (20), formula (21) formula will

Replace with

Thus, in the user shown in formula (5) formula receives signal expression, order $F_l=V_{H_l},$ And user I will receive signal times with

The useful signal that receives of user I can be expressed as:

Therefore, channel capacity expression formula C _lCan be expressed as:

Wherein, ${\mathrm{\λ}}_{G_l}^i(i=1,...,M)$ Be G _lG _l ^HCharacteristic value.Compare (19) formula, (23) formula will

Replace with

So far, through base station pre-coding matrix F _lWith relaying filtering matrix W _l, first each parallel independent channel after heavily decomposing is broken down into again M independently parallel subchannel, and the gain of every sub-channels is

Wherein

Be the first hop channel gain of base station to relay station, ${\mathrm{\γ}}_{G_l}^i={\mathrm{\ρ}}_l{\mathrm{\λ}}_{G_l}^i/({\mathrm{\ρ}}_l{\mathrm{\λ}}_{G_l}^i+1)$ Be the second hop channel gain of relay station to the user.

Relaying filtering matrix W is discussed at last _lKnown W _l=B _lX _lA _l, namely at first relay station passes through matrix A _lMany base stations mixed signal is separated, then use matrix X _lThe multiple signals that separated are processed, used at last matrix B _lCarry out forward direction filtering and send to all users, wherein matrix A _lAnd B _lDiscussed the front, and X _lRelay process matrix for the unknown.Again by getting conclusion $W_l=V_{G_l}{U}_{H_l}^H,$ Can derive relay process matrix X _lExpression formula is: $X_l=B_l^{+}{V}_{G_l}{U}_{H_l}^H{A}_l^{+}.$ A wherein _l ⁺And B _l ⁺Be respectively matrix A _lAnd B _lGeneralized inverse matrix, and have

The power partition coefficient that the parallel independent channel of I bar is set is ω _l, the suppose relay power amplification coefficient power amplification ratio is ρ _l, ρ _lSize equals the ratio of the transmitting power of relay station on the parallel independent channel of I bar and the received power on this channel, is expressed as:

Wherein, have $\underset{l=1}{\overset{L}{\mathrm{\Σ}}}{\mathrm{\ω}}_l=1,$ || || _FExpression Frobenius (not Robbie's house) norm.

Known $W_l=V_{G_l}{U}_{H_l}^H,$ Have:

With (25) formula substitution (23) formula, and ${\left|\right|H_l\left|\right|}_F^2=\underset{m=1}{\overset{M}{\mathrm{\Σ}}}{\mathrm{\λ}}_{H_l}^m,$ The capacity expression formula that can get I bar independent channel is:

Overall system capacity is: $C=\underset{l=1}{\overset{L}{\mathrm{\Σ}}}{C}_l.$ For making overall system capacity maximum, should be every independent channel and select suitable power partition coefficient ω _lThus, can set up following capacity optimization problem:

$\mathrm{Max\; C}$

$s.t.\underset{l=1}{\overset{L}{\mathrm{\Σ}}}{\mathrm{\ω}}_l=1---\left(27\right)$

For the DF pattern:

For the I bar independent channel after the first heavy channel decomposing, use SVD and obtain M bar data streams in parallel (i.e. the second heavy channel decomposing).The channel capacity that the DF that is applied thus forwards is:

ω wherein _lThe power partition coefficient that represents I bar channel, and have $\underset{l=1}{\overset{L}{\mathrm{\Σ}}}{\mathrm{\ω}}_l=1;$ ${\mathrm{\Σ}}_l=\mathrm{diag}\{{\mathrm{\γ}}_l^1,{\mathrm{\γ}}_l^2,...,{\mathrm{\γ}}_l^M\}$ During expression second is jumped for the power partition coefficient of each data streams in parallel.Order

With

Represent respectively channel matrix H _lH _l ^HAnd G _lG _l ^HCharacteristic value, DF channel capacity C _lAlso can be expressed as:

By (29) formula as seen, the DF pattern relates to the power division process twice, corresponds respectively to independent channel and data streams in parallel after double channel decomposing, uses respectively ω _lAnd γ _l ⁱExpression.

This embodiment by backward filtering matrix, relay process matrix and the forward direction filtering matrix that sets in advance, has completed the first heavy channel decomposing process under the AF pattern.Under the DF pattern, by backward filtering matrix and the forward direction filtering matrix that sets in advance, completed the first heavy channel decomposing process.To resolve into the parallel independent channel at many " single base station-single relaying-alone families " for the mixed channel of " many base stations-single relaying-multi-user " of a plurality of base stations,

This embodiment is under AF and DF pattern, process by the precoding processing of base station side and the relaying filtering of relay station side, a corresponding user's a parallel independent channel is further resolved into a plurality of parallel subchannels, and each subchannel is corresponding to user's a data flow.Suppress thereby carry out presence of intercell interference by relay station, eliminated the minizone co-channel interference.Increase the degree of freedom of system, created prerequisite for further improving the power system capacity performance.

Embodiment three

1) for finding the solution the capacity optimization problem in the heavy channel decomposing process of first under above-mentioned AF and DF pattern, adopt respectively the average power allocation algorithm and find the solution based on the optimum allocation algorithm of heredity, the below introduces respectively this two algorithms:

(1), average power allocation algorithm:

Relay station is every parallel independent channel mean allocation transmitting power, i.e. ω _l=1/L.

(2), based on the optimum allocation algorithm of heredity:

Make that chromosome is (ω ₁, ω ₂..., ω _L), fitness function is f=C (ω ₁, ω ₂..., ω _i), population quantity is 30, and crossover probability is 0.5, and the variation probability is 0.02, and genetic algebra was 150 generations.The detailed process of genetic algorithm is as follows:

Initialization chromosome: generate at random ω _i∈ (0,1), and satisfy $\underset{l=1}{\overset{L}{\mathrm{\Σ}}}{\mathrm{\ω}}_l\≤1$ Chromosome.

Estimate chromosome: application adaptation function f=C (ω ₁, ω ₂..., ω _i) try to achieve every chromosomal fitness.

Chromosome is selected: adopt the method for rotation roulette wheel, roulette wheel is come the selective staining body by every chromosomal fitness, and each rotation is all that new population is selected a chromosome.

Chiasma: select parent chromosome with crossover probability 0.5, and parent chromosome is minute right at random, every pair of parent chromosome intersections that count, generation child chromosome.

Chromosomal variation: select the variation that counts of parent chromosome, generation child chromosome with variation probability 0.02.

Chromosome after cross and variation is chromosome of new generation, repeating step 2)-5), until produce the 150th generation chromosome, select that in the 150th generation chromosome, the highest chromosome of fitness is optimum chromosome.

With (the ω that comprises in above-mentioned optimum chromosome ₁, ω ₂..., ω _L) respectively as the power partition coefficient of every parallel independent channel.

2) under above-mentioned AF and DF pattern, the power division process in the second heavy channel decomposing process is as follows:

The parallel subchannel corresponding to every data streams in parallel of a user that the above-mentioned second heavy channel decomposing is obtained carries out power division.

For the AF pattern, by finding the solution optimum relay process matrix X _lEach user's M data streams in parallel carried out power division, and (power partition coefficient of double bounce is used respectively

With

Expression).

In the DF pattern, owing to redistributing data flow on each antenna by the mode of recompile, therefore can be to realizing further power division between the second resulting data streams in parallel of heavy channel decomposing.

DF pattern using water-filling algorithm is found the solution the optimal power allocation coefficient gamma of every data streams in parallel of user I _li, have:

${\mathrm{\γ}}_l^i={\mathrm{\μ}}_l-\frac{N}{M}\·\frac{1}{{\mathrm{\ω}}_{l}L{\mathrm{\λ}}_{G_l}^i}---\left(30\right)$

μ wherein _lBe the water filling height.Because the power sum of every data streams in parallel equals relay station for total transmitting power of user I, therefore have:

$\underset{i=1}{\overset{M}{\mathrm{\Σ}}}{\mathrm{\γ}}_l^i=L{\mathrm{\ω}}_{l}N---\left(31\right)$

Can find the solution water filling height μ by above-mentioned (30) (31) formula _l

For the invention described above embodiment described base station precoding and relaying filters solutions and corresponding relaying power allocation scheme based on double channel decomposing, different forward mode (AF have been verified by Computerized Numerical Simulation, DF), different base station (user) quantity, and the average system capacity performance under different dual-mode antenna number and base station transmitting power.Simulation parameter is as shown in table 1:

Table 1 simulation parameter

Base station transmitting power (db)	0-15
		Radius of society (m)	1000
Shared relay station is to user's distance (m)	200
		Noise power (dbm/Hz)	174
System bandwidth (MHz)	5
		Every channel width (kHz)	180
Base station-shared relay station Pathloss model (db)	L LOS＝42.5+23.5*log 10(d)+20*log 10(f/f 0)
		Shared relay station-user Pathloss model (db)	L NLOS＝31.5+35.7*log 10(d)+20*log 10(f/f 0)

Centre frequency f0 (MHz)	5
		Carrier frequency f (MHz)	5

Based on above-mentioned simulation parameter, the described scheme of the embodiment of the present invention and " ZF scheme " of the prior art and " non-relay interference inhibition " scheme have been carried out numerical simulation.Simulation result figure is as shown in Figure 5 and Figure 6:

Can find out by Fig. 5 and Fig. 6, the optimal power allocation (.opt) in the described scheme of the embodiment of the present invention and average power allocation (.avg) are all higher than " ZF scheme " of the prior art and " non-relay interference inhibition " scheme.

In the described scheme of the embodiment of the present invention, the performance difference of AF and two kinds of forward modes of DF is little, by contrast, the volumetric properties of DF is a little more than AF (1bits/s/Hz left and right), this is mainly because the AF pattern has also been amplified noise in the amplification forwarding useful signal, makes the signal to noise ratio of receiving terminal descend.

This embodiment is for above-mentioned double channel decomposing process, propose the power distribution algorithm of trunk side, can take full advantage of the double bounce channel gain, improved optimal power allocation and the average power allocation of system, thereby the raising power system capacity, the throughput performance of raising Cell Edge User.

One of ordinary skill in the art will appreciate that all or part of flow process that realizes in above-described embodiment method, to come the relevant hardware of instruction to complete by computer program, described program can be stored in a computer read/write memory medium, this program can comprise the flow process as the embodiment of above-mentioned each side method when carrying out.Wherein, described storage medium can be magnetic disc, CD, read-only store-memory body (Read-Only Memory, ROM) or random store-memory body (Random Access Memory, RAM) etc.

The embodiment of the present invention also provides a kind of side signal transmission subtraction unit, and its specific implementation structure specifically can comprise as shown in Figure 7:

The first channel decomposing module 71, be used for processing by relaying filtering, the mixed channel that a plurality of base stations are connected to a plurality of users by described relay station is decomposed into a plurality of single base stations and is connected to the independent channel at alone family by described relay station, and each described independent channel corresponding described single base station is transferred to the data at described alone family by relay station;

Second channel decomposing module 72, be used for by base station pre-coding matrix and relaying filtering matrix, each described independent channel is resolved into a plurality of single base stations be connected to the subchannel at alone family by described relay station, each described subchannel corresponding described single base station data flow in the data at described alone family.

Described device can also comprise:

Power division module 73, be used under the amplification forwarding pattern, obtain described single base station to the first hop link of described relay station and described relay station to the channel characteristic value of second hop link at alone family by finding the solution optimum relay process matrix, according to the channel characteristic value of described the first hop link and the second hop link, a plurality of data streams in parallel at described alone family are carried out power division; Perhaps

Under the decoding forward mode, use the water-filling algorithm selection corresponding to the power partition coefficient of each sub-channels of every data flow at described alone family; , be assigned to respectively on described each sub-channels the gain that described the first hop channel gain and the second hop channel gain and multiply each other and obtain according to the power partition coefficient of each sub-channels.

Described second channel decomposing module 72 can comprise:

Channel total capacity control module 721, be used for to adopt the average power allocation algorithm or based on the optimum allocation algorithm of heredity, select each described single base station to be connected to the power partition coefficient of the independent channel at alone family by described relay station, make the channel total capacity between described single base station and described alone family reach maximum;

Relaying filtering matrix acquisition module 722, be used for obtaining optimum described relaying filtering matrix according to described many base stations and the channel total capacity between described alone family of described maximum, channel matrix three's the product that makes optimum described relaying filtering matrix, described pre-coding matrix, described single base station be connected to the independent channel at alone family by described relay station is diagonal matrix.

Said apparatus can be applied in collaborative network.

In sum, the embodiment of the present invention has resolved into many base stations-single relaying-multi-user's mixed channel the independent channel at a plurality of single base stations-single relaying-alone family, and each independent channel after decomposing further resolves into a plurality of parallel data flow.Thereby increased the degree of freedom of system, created prerequisite for further improving the power system capacity performance.

The embodiment of the present invention is carried out presence of intercell interference by shared relay station and is suppressed, and has eliminated the minizone co-channel interference.For shared relay scene, the embodiment of the present invention has proposed double channel decomposing method, has designed base station precoding and relaying filters solutions, and has proposed the power distribution algorithm of trunk side.Simulation result shows, the embodiment of the present invention can take full advantage of the double bounce channel gain, improves optimal power allocation and the average power allocation of system, thereby improves power system capacity, improves the throughput performance of Cell Edge User.

Each base station of the embodiment of the present invention does not need to know the channel information between itself and adjacent cell user, does not increase Signalling exchange between the base station, does not change existing air protocol.

The above; only for the better embodiment of the present invention, but protection scope of the present invention is not limited to this, anyly is familiar with those skilled in the art in the technical scope that the present invention discloses; the variation that can expect easily or replacement are within all should being encompassed in protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection range of claim.

Claims (11)

1. a method for transmitting signals, is characterized in that, comprising:

Relay station is processed by relaying filtering, and the mixed channel that a plurality of base stations are connected to a plurality of users by described relay station is decomposed into a plurality of single base stations and is connected to the independent channel at alone family by described relay station;

Process by the precoding processing of base station side and the relaying filtering of relay station side, each described independent channel is resolved into a plurality of single base stations be connected to the subchannel at alone family by described relay station, each described subchannel corresponding described single base station data flow in the data at described alone family.

2. method for transmitting signals according to claim 1, it is characterized in that, described relay station is processed by relaying filtering, and the mixed channel that a plurality of base stations are connected to a plurality of users by described relay station is decomposed into a plurality of single base stations and is connected to the independent channel at alone family by described relay station, comprising:

The backward filtering matrix of described relay station by arranging becomes a plurality of single base stations to the independent channel of relay station the channel decomposing between described many base stations and described relay station;

Relay process matrix and the forward direction filtering matrix of described relay station by arranging decomposes the independent channel of each described single base station to relay station, obtains a plurality of single base stations and is connected to the independent channel at alone family by described relay station.

3. method for transmitting signals according to claim 1 and 2, it is characterized in that, process by the precoding processing of base station side and the relaying filtering of relay station side, each described independent channel resolved into a plurality of single base stations be connected to the subchannel at alone family by described relay station, comprising:

Pre-coding matrix by the base station side setting carries out precoding processing to the transmitting data of single base station, then sends the data to relay station, and described pre-coding matrix obtains according to the channel matrix of described independent channel;

The transmitting data that described relay station sends over described single base station by the relaying filtering matrix carries out filtering to be processed, described independent channel is resolved into a plurality of subchannels, the data flow of the described single base station of each described subchannel transmission in the data at described alone family, the channel matrix of described pre-coding matrix, described independent channel and relaying filtering matrix three's product is diagonal matrix.

4. method for transmitting signals according to claim 3, is characterized in that, described method also comprises:

Distribute respectively power by the independent channel that described relay station is connected to alone family for each described single base station, make the channel total capacity between described single base station and described alone family reach maximum, obtain optimum described relaying filtering matrix according to the channel total capacity of described maximum.

5. method for transmitting signals according to claim 4, is characterized in that, described method also comprises:

Adopt the average power allocation algorithm or based on the optimum allocation algorithm of heredity, select each described single base station to be connected to the power partition coefficient of the independent channel at alone family by described relay station, make the channel total capacity between described single base station and described alone family reach maximum.

6. method for transmitting signals according to claim 4, is characterized in that, described method also comprises:

Under the amplification forwarding pattern, obtain described single base station to the first hop link of described relay station and described relay station to the channel characteristic value of second hop link at alone family by finding the solution optimum relay process matrix, according to the channel characteristic value of described the first hop link and the second hop link, a plurality of data streams in parallel at described alone family are carried out power division.

7. method for transmitting signals according to claim 4, is characterized in that, described method also comprises:

Under the decoding forward mode, use the water-filling algorithm selection corresponding to the power partition coefficient of each sub-channels of every data flow at described alone family;

, be assigned to respectively on described each sub-channels the gain that second hop channel of described single base station to the first hop channel gain of described relay station and described relay station to alone family gains and multiply each other and obtain according to the power partition coefficient of each sub-channels.

8. method for transmitting signals according to claim 1, is characterized in that, described method is applicable to the collaborative network framework under the amplification forwarding pattern in ofdm system and the forward mode of decoding.

9. a signal transmitting apparatus, is characterized in that, is arranged in relay station, comprising:

The first channel decomposing module, be used for processing by relaying filtering, the mixed channel that a plurality of base stations are connected to a plurality of users by described relay station is decomposed into a plurality of single base stations and is connected to the independent channel at alone family by described relay station, and each described independent channel corresponding described single base station is transferred to the data at described alone family by relay station;

The second channel decomposing module, be used for by base station pre-coding matrix and relaying filtering matrix, each described independent channel is resolved into a plurality of single base stations be connected to the subchannel at alone family by described relay station, each described subchannel corresponding described single base station data flow in the data at described alone family.

10. signal transmitting apparatus according to claim 9, is characterized in that, described device also comprises:

The power division module, be used under the amplification forwarding pattern, obtain described single base station to the first hop link of described relay station and described relay station to the channel characteristic value of second hop link at alone family by finding the solution optimum relay process matrix, according to the channel characteristic value of described the first hop link and the second hop link, a plurality of data streams in parallel at described alone family are carried out power division; Perhaps,

Under the decoding forward mode, use the water-filling algorithm selection corresponding to the power partition coefficient of each sub-channels of every data flow at described alone family; , be assigned to respectively on described each sub-channels the gain that described the first hop channel gain and the second hop channel gain and multiply each other and obtain according to the power partition coefficient of each sub-channels.

11. according to claim 9 or 10 described signal transmitting apparatus is characterized in that, described second channel decomposing module comprises:

Channel total capacity control module, be used for to adopt the average power allocation algorithm or based on the optimum allocation algorithm of heredity, select each described single base station to be connected to the power partition coefficient of the independent channel at alone family by described relay station, make the channel total capacity between described single base station and described alone family reach maximum;

Relaying filtering matrix acquisition module, be used for obtaining optimum described relaying filtering matrix according to described single base station and the channel total capacity between described alone family of described maximum, channel matrix three's the product that makes optimum described relaying filtering matrix, described pre-coding matrix, described single base station be connected to the independent channel at alone family by described relay station is diagonal matrix.

Images