CN102257778B - Channel quality estimation method, device and wireless receiver - Google Patents

Abstract

The invention discloses a channel quality estimation method, a device and a wireless receiver, referring to the wireless communication technical field and solves the problem in existing channel quality estimation methods that calculated effective signal-noise ratio is not accurate, which causes the inaccuracy of the channel quality estimation. In the embodiment of the invention, in a process of calculating an equilibrium matrix, a sum of a channel matrix and an estimation difference of the channel matrix, i.e.,a channel estimation matrix is employed such that the effective signal-noise ratio by employing the equilibrium matrix is more accurate and thereby the accuracy of the channel quality estimation. The embodiment of the invention is mainly applied on occasions of single data flow sending and multi-receiving antenna in a wireless communication system.

Description

Channel quality estimation method, device and wireless receiver

Technical field

The present invention relates to wireless communication technology field, relate in particular to channel quality estimation method, device and wireless receiver.

Background technology

At radio MIMO (Multiple-Input Multiple-Output, multiple-input and multiple-output) in communication system, often need to be to effective Signal to Interference plus Noise Ratio of wireless environment (Signal to Interference plus Noise Ratio, referred to as: SINR) estimate to understand channel quality and utilize this information to improve power system capacity, such as: signal receiving end obtains CQI (Channel Quality Indication by estimating effective Signal to Interference plus Noise Ratio and then estimation, channel quality instruction) and PMI (Precoding Matrix Index, pre-coding matrix index), then CQI and PMI are fed back to signal sending end, select be applicable to the modulating-coding pattern of current channel transfer characteristic and carry out wave beam forming at signal sending end with index signal transmitting terminal, thereby raising power system capacity.

The effectively signal to noise ratio of SINR after the equilibrium of wireless MIMO communication system middle finger, this parameter can reflect receiver performance.Adopt single data stream to send data for the transmitting terminal of radio MIMO system, receiving terminal disturbs the scene that suppresses to merge (Interference Rejection Combining) to the reception signal of multiple antennas, the computational methods of existing effective SINR comprise: calculate and obtain balanced matrix according to selected system estimation criterion, ideal communication channel matrix and interference correlation matrix; According to signal the balanced front signal receiving from reception antenna and balanced matrix computations equilibrium; According to the effective SINR of calculated signals after this equilibrium.

In the process of the effective SINR of above-mentioned calculating, inventor finds that in prior art, at least there are the following problems: while calculating balanced matrix, used ideal communication channel matrix, but this matrix the unknown in the actual moving process of communication system, must rely on and estimate just can obtain (being channel estimate matrix), because channel matrix and ideal communication channel matrix that this estimation obtains can not be in full accord, cause calculating balanced rear signal with this equilibrium matrix inaccurate, thereby cannot obtain effective SINR accurately, and then have influence on the accuracy of channel quality estimation, cause receiving terminal cannot utilize effective SINR to improve power system capacity, may reduce on the contrary power system capacity.

Summary of the invention

Embodiments of the invention provide a kind of channel quality estimation method, device and wireless receiver, can obtain accurately effectively SINR, and then can improve the accuracy of channel quality estimation.

For achieving the above object, embodiments of the invention adopt following technical scheme:

A kind of channel quality estimation method, comprising: by channel matrix and this channel matrix evaluated error addition obtains balanced matrix G; According to the balanced front signal receiving from reception antenna and described balanced matrix G calculates the effective Signal to Interference plus Noise Ratio for estimated channel quality.

A kind of channel quality estimation apparatus, comprising: computing module, and for by channel matrix and this channel matrix evaluated error addition obtains balanced matrix G; Quality assessment modules, the balanced front signal receiving from reception antenna for basis and described balanced matrix G calculates the effective Signal to Interference plus Noise Ratio for estimated channel quality.

The embodiment of the present invention also provides a kind of wireless receiver that comprises described channel quality estimation apparatus.

In channel quality estimation method, device and wireless receiver that the embodiment of the present invention provides, in the time calculating balanced matrix, evaluated error sum by channel matrix and this channel matrix obtains channel estimate matrix, owing to having taken into full account that the error component of channel matrix is on the impact of channel quality estimation, make to adopt effective SINR accuracy of this equilibrium matrix computations acquisition higher, thereby improved the accuracy of channel quality estimation.

Brief description of the drawings

In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, to the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the flow chart of the channel quality estimation method of the embodiment of the present invention 1;

Fig. 2 is the block diagram of the channel quality estimation apparatus of the embodiment of the present invention 1;

Fig. 3 is the block diagram of the channel quality estimation apparatus of the embodiment of the present invention 3.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiment.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtaining under creative work prerequisite, belong to the scope of protection of the invention.

Embodiment 1

The present embodiment provides a kind of channel quality estimation method, can be applicable in wireless receiver, and as shown in Figure 1, the method comprises the steps.

101, by channel matrix and this channel matrix evaluated error addition obtains balanced matrix G.

Be specially, in the time calculating balanced matrix, adopted channel matrix and this channel matrix evaluated error sum, has introduced the evaluated error of channel matrix this evaluated error with channel matrix sum has been described the estimated value of channel matrix exactly, and making to calculate the balanced matrix G obtaining has better portfolio effect to the signal receiving from reception antenna.

102, according to the balanced front signal receiving from reception antenna and described balanced matrix G calculates the effective Signal to Interference plus Noise Ratio for estimated channel quality.

Particularly, use the balanced matrix G that calculates acquisition by step 101 to the balanced front signal receiving from reception antenna carry out, after equilibrium calculation, can obtaining the signal after equilibrium.Can calculate and obtain effective Signal to Interference plus Noise Ratio according to the signal after this equilibrium again.

In the present embodiment due to calculating when balanced matrix, adopt the evaluated error sum of channel matrix and this channel matrix, should and be channel estimate matrix, make to adopt effective SINR accuracy of this equilibrium matrix computations acquisition higher, thereby improved the accuracy of channel quality estimation.

The present embodiment also provides a kind of channel quality estimation apparatus, and as shown in Figure 2, this device comprises: computing module 21, and for by channel matrix and this channel matrix evaluated error addition obtains balanced matrix G; Quality assessment modules 22, the balanced front signal receiving from reception antenna for basis and described balanced matrix G calculating is for effective Signal to Interference plus Noise Ratio of estimated channel quality, to estimate the quality of channel.Computing module 21 and quality assessment modules 22 can be realized by hardware, for example, can be respectively processor.

In above-mentioned channel quality estimation apparatus, the performed method of each module describes in detail in above-mentioned channel quality estimation method, does not repeat them here.

In the channel quality estimation apparatus that the present embodiment provides, due in the time adopting computing module to calculate balanced matrix, adopt the evaluated error sum of channel matrix and this channel matrix, should and be channel estimate matrix, make to adopt effective SINR accuracy of this equilibrium matrix computations acquisition higher, thereby improved the accuracy of channel quality estimation.

Embodiment 2

The present embodiment provides a kind of channel quality estimation method, and the method is applied in the scene of single data stream transmission, multiple receive antenna, and the method comprises the steps.

Step 1, according to channel matrix and evaluated error sum calculates balanced matrix G.

Wherein, balanced matrix G can be according to formula calculate and obtain, a is greater than 0 constant, according to the difference of adopted system estimation criterion and difference, for interference correlation matrix.

Balanced Matrix Computation Formulas with prior art compare, the present embodiment, in the computational process of balanced matrix G, has been introduced the evaluated error of channel matrix this estimation mistake described exactly the estimated value of channel matrix with channel matrix sum, making to calculate the balanced matrix obtaining has better portfolio effect to the signal receiving from reception antenna.

When hypothesis channel matrix be estimated as Linear Estimation, and estimation coefficient carried out normalization, and supposes constant a=1 in balanced Matrix Computation Formulas, the evaluated error of channel matrix computing formula can be wherein, the estimation coefficient matrix that W is channel matrix, dimension is N _r× N, can select the signal receiving from reception antenna part signal as treating estimating resource, a bit of time resource or frequency resource near this resource are chosen to be to observed quantity, in this section in observed quantity, can suppose that channel matrix is invariable, suppose to disturb between each observed quantity uncorrelated, and the statistical property of each interference signal is identical simultaneously.N _rfor the number of reception antenna, N is observed quantity dimension, for corresponding to interference vector described observed quantity, N dimension.

Element { W} in the estimation coefficient matrix W of channel matrix _ijfor the estimation coefficient of channel matrix corresponding to different reception antennas.The estimation coefficient of supposing the channel matrix that different reception antennas are corresponding is identical, i.e. { W} _ij={ W} _mj, i ≠ m, element { W} _ijcan use w _j, j=1,2 ..., N represents.

? wherein, u ' _{i, j}for the interference of corresponding i reception antenna and j observed quantity.Due in observed quantity dimension, between each observed quantity, disturb uncorrelatedly, therefore have:

$E\left(W{\stackrel{\→}{u}}^{\′}{\left(W{\stackrel{\→}{u}}^{\′}\right)}^H\right)=\left(\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}{w_i}^2\right)R_{\mathrm{uu}}=\mathrm{\β}{R}_{\mathrm{uu}}---\left(1\right)$

In above-mentioned formula (1), the conjugate transpose of subscript H representing matrix.

Can be obtained the computing formula of balanced matrix G by above-mentioned derivation

The balanced front signal that step 2, basis receive from reception antenna and described balanced matrix G calculates effective Signal to Interference plus Noise Ratio, to estimate the quality of channel.

Particularly, can, by the mode of prior art, first pass through formula calculate balanced rear signal wherein for balanced front signal.The system model of wireless MIMO communication system is: wherein for channel matrix, in the present embodiment for N _rthe channel matrix of × 1 dimension.S is the signal that transmitting antenna sends, for the interference vector of channel, wherein, corresponding to interference vector observed quantity, N dimension interference vector with channel between relation can be formulated as: because s is single data stream, its value is constant.By trying to achieve before substitution can obtain balanced rear signal computing formula.Those skilled in the art can complete signal after equilibrium according to the computational methods of prior art solve, by signal after balanced in available signal power solve with the ratio of interfering signal power.But for the ease of understanding, slightly explain solving derivation below.

$\hat{s}={(\stackrel{\→}{h}+W{\stackrel{\→}{u}}^{\′})}^H{R}_{\mathrm{uu}}^{-1}(\stackrel{\→}{h}s+\stackrel{\→}{u})={\stackrel{\→}{h}}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{h}s+{\left(W{\stackrel{\→}{u}}^{\′}\right)}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{h}s+{\stackrel{\→}{h}}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{u}+{\left(W{\stackrel{\→}{u}}^{\′}\right)}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{u}---\left(2\right)$

Easily find out to only have Section 1 can think useful signal in formula (2), other are disturbed pollution all, becomes distracter, establishes its performance number be respectively I according to distracter order from left to right ₁, I ₂, I ₃.

The computing formula of signal power P is:

$P={\stackrel{\→}{h}}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{h}\mathrm{ss}*{\stackrel{\→}{h}}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{h}={\left({\stackrel{\→}{h}}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{h}\right)}^2---\left(3\right)$

Interference power I ₁, I ₂, I ₃computing formula respectively as follows:

$I_1=E({\left(W{\stackrel{\→}{u}}^{\′}\right)}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{h}\mathrm{ss}*{\stackrel{\→}{h}}^H{R}_{\mathrm{uu}}^{-1}\left(W{\stackrel{\→}{u}}^{\′}\right))=\mathrm{trace}\left(E\left({\stackrel{\→}{h}}^H{R}_{\mathrm{uu}}^{-1}\left(W{\stackrel{\→}{u}}^{\′}\right){\left(W{\stackrel{\→}{u}}^{\′}\right)}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{h}\right)\right)=\mathrm{\β}{\stackrel{\→}{h}}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{h}---\left(4\right)$

$I_2=E\left({\stackrel{\→}{h}}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{u}{\stackrel{\→}{u}}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{h}\right)={\stackrel{\→}{h}}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{h}---\left(5\right)$

$I_3=E(\left({\left(W{\stackrel{\→}{u}}^{\′}\right)}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{u}\right)\left({\left(W{\stackrel{\→}{u}}^{\′}\right)}^H{R_{\mathrm{uu}}^{-1}\stackrel{\→}{u})}^H\right)=E\left({\left(W{\stackrel{\→}{u}}^{\′}\right)}^H{R}_{\mathrm{uu}}^{-1}\stackrel{\→}{u}{\stackrel{\→}{u}}^H{R}_{\mathrm{uu}}^{-1}\left(W{\stackrel{\→}{u}}^{\′}\right)\right)=E\left({\left(W{\stackrel{\→}{u}}^{\′}\right)}^H{R}_{\mathrm{uu}}^{-1}\left(W{\stackrel{\→}{u}}^{\′}\right)\right)$

, right carry out Cholesky decomposition, and bring formula (1) into above formula, above formula can be rewritten as: $I_3=E\left({\left(\mathrm{LW}{\stackrel{\→}{u}}^{\′}\right)}^H\left(\mathrm{LW}{\stackrel{\→}{u}}^{\′}\right)\right)=\mathrm{trace}\left(\left(\mathrm{LW}{\stackrel{\→}{u}}^{\′}\right){\left(\mathrm{LW}{\stackrel{\→}{u}}^{\′}\right)}^H\right)=\mathrm{trace}\left(\mathrm{\β}{\mathrm{LR}}_{\mathrm{uu}}{L}^H\right)$

$=\mathrm{trace}\left({\mathrm{\βLL}}^{-1}{\left(L^H\right)}^{-1}{L}^H\right)=\mathrm{\β}{N}_R---\left(6\right)$

In above-mentioned formula (6), trace () is the computing of Matrix Calculating mark.

Then according to the computing formula of effective SINR and formula (3)～(6), can obtain the Signal to Interference plus Noise Ratio of this communication system,

Effective SINR result that effective SINR result that the present embodiment calculates and prior art calculate compare and introduced the β item relevant to evaluated error, make the effective SINR calculating more accurate, thereby can estimate exactly the quality of channel.

Embodiment 3

The present embodiment provides a kind of channel quality estimation apparatus, can be arranged in wireless receiver, and as shown in Figure 3, this device comprises: computing module 31 can be processor, for by channel matrix and this channel matrix evaluated error addition obtains balanced matrix G; Quality assessment modules 32, can be another processor, the balanced front signal receiving from reception antenna for basis and described balanced matrix G calculates the effective Signal to Interference plus Noise Ratio for estimated channel quality.

Computing module 31 can comprise the first computing unit 311, and this first computing unit 311 can be a processor unit, for according to formula calculate and obtain described balanced matrix G, wherein, a is greater than 0 constant, according to the difference of adopted system estimation criterion and difference; for interference correlation matrix.

Computing module also can comprise the second computing unit 312, and this second computing unit 312 can be another processor unit, for passing through formula calculate and obtain described evaluated error and will calculate send to described the first computing unit 311; Wherein, W be described channel matrix, N _rthe estimation coefficient matrix of × N dimension, wherein, N _rfor the number of reception antenna, N is observed quantity dimension; for corresponding to interference vector described observed quantity, N dimension.

Quality assessment modules 32 can comprise: the 3rd computing unit 321 can be a processor unit, for according to the described balanced front signal receiving from reception antenna and described balanced matrix G calculates balanced rear signal the 4th computing unit 322, can be also a processor unit, for according to signal after described equilibrium calculate described effective Signal to Interference plus Noise Ratio.

The performed method of above-mentioned each module have been described in detail in embodiment 2, does not repeat them here.Described in the present embodiment, each method and apparatus is applied in MIMO wireless receiver conventionally, for estimating effective Signal to Interference plus Noise Ratio SINR.

In the present embodiment, due in the time adopting computing module to calculate balanced matrix, adopt the evaluated error sum of channel matrix and this channel matrix, should and be channel estimate matrix, make to adopt effective SINR accuracy of this equilibrium matrix computations acquisition higher, thereby improved the accuracy of channel quality estimation.

Through the above description of the embodiments, those skilled in the art can be well understood to the mode that the present invention can add essential common hardware by software and realize, and can certainly pass through hardware, but in a lot of situation, the former is better execution mode.Based on such understanding, the part that technical scheme of the present invention contributes to prior art in essence in other words can embody with the form of software product, this computer software product is stored in the storage medium can read, as the floppy disk of computer, hard disk or CD etc., comprise that some instructions are in order to make a computer equipment (can be personal computer, server, or the network equipment etc.) carry out the method described in each embodiment of the present invention.

The embodiment of the present invention is mainly used in the scene of single data stream transmission, multiple receive antenna in wireless communication system.

The above; be only the specific embodiment of the present invention, but protection scope of the present invention is not limited to this, any be familiar with those skilled in the art the present invention disclose technical scope in; the variation that can expect easily or replacement, 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 described claim.

Claims (4)

1. a channel quality estimation method, is characterized in that, comprising:

By channel matrix and this channel matrix evaluated error addition obtains balanced matrix G;

According to the balanced front signal receiving from reception antenna and described balanced matrix G calculates the effective Signal to Interference plus Noise Ratio for estimated channel quality;

Described balanced matrix G is according to formula calculate and obtain, wherein, a is greater than 0 constant, for interference correlation matrix;

Described evaluated error by formula calculate and obtain, wherein,

W be described channel matrix, N _rthe estimation coefficient matrix of × N dimension, wherein, N _rfor the number of reception antenna, N is observed quantity dimension; for corresponding to interference vector described observed quantity, N dimension;

The balanced front signal that described basis receives from reception antenna and described balanced matrix G calculating comprises for effective Signal to Interference plus Noise Ratio of estimated channel quality:

Based on following formula, according to the described balanced front signal receiving from reception antenna and described balanced matrix G calculates balanced rear signal

$\hat{s}=G\stackrel{\→}{r};$

According to signal after described equilibrium calculate described effective Signal to Interference plus Noise Ratio.

2. method according to claim 1, is characterized in that, signal after described equilibrium comprise:

Useful signal the first distracter the second distracter the 3rd distracter

Wherein, s is the signal that transmitting antenna sends, for the interference vector of channel.

3. a channel quality estimation apparatus, is characterized in that, comprising:

Computing module, for by channel matrix and this channel matrix evaluated error addition obtains balanced matrix G;

Quality assessment modules, the balanced front signal receiving from reception antenna for basis and described balanced matrix G calculates the effective Signal to Interference plus Noise Ratio for estimated channel quality;

Described computing module comprises the first computing unit, and this first computing unit is used for according to formula calculate and obtain described balanced matrix G, wherein, a is greater than 0 constant, for interference correlation matrix;

Described computing module also comprises the second computing unit, and this second computing unit is used for passing through formula calculate and obtain described evaluated error and will calculate send to described the first computing unit; Wherein,

W be described channel matrix, N _rthe estimation coefficient matrix of × N dimension, wherein, N _rfor the number of reception antenna, N is observed quantity dimension; for corresponding to interference vector described observed quantity, N dimension;

Described quality assessment modules comprises:

The 3rd computing unit, for according to the described balanced front signal receiving from reception antenna and described balanced matrix G calculates balanced rear signal

The 4th computing unit, for according to signal after described equilibrium calculate described effective Signal to Interference plus Noise Ratio.

4. a wireless receiver, is characterized in that, comprises device as claimed in claim 3.