CN103391266A - Frequency domain channel response obtaining method and device - Google Patents

Abstract

The invention discloses a frequency domain channel response obtaining method and device. The method includes calculating a first noise amplitude threshold value g by using time domain channel response; calculating a second noise amplitude threshold value G by using the time domain channel response and the first noise amplitude threshold value g; calculating a third noise amplitude threshold value G' by using the second noise amplitude threshold value G; obtaining noise-restrained frequency domain channel response by using the third noise amplitude threshold value G'. By means of the method and device, channel estimation performance can be improved, and especially channel estimation performance under small bandwidth can be improved effectively.

Description

A kind of acquisition methods of domain channel response and equipment

Technical field

The present invention relates to communication technical field, especially related to a kind of acquisition methods and equipment of domain channel response.

Background technology

Channel estimating refers to the time-frequency position that utilizes known pilot signal transmitted and pilot tone to send, and the data-signal that receives in corresponding time-frequency position, obtains the process of spatial channel information, namely obtains domain channel response.Channel estimation process schematic diagram as shown in Figure 1, with LTE(Long Term Evolution, Long Term Evolution) downlink system is example, and it is S that known descending pilot frequency sends sequence, and the signal that receives is Y, and the spatial frequency domain channel is H+n, and H represents the impulse response of wireless fading channel, n represents white Gaussian noise, Y=(H+n) S, thus can estimate domain channel response

In order further to improve the precision of channel estimating, and estimate simultaneously noise power-value, can also adopt time domain to get the method for window; Its detailed process comprises: first frequency domain channel is changed to time domain, again according to CP(Cyclic Prefix, Cyclic Prefix) length or prior information define the position with the signal time delay maximum diameter, then take out the noise in time domain footpath that does not contain useful signal power, the calculating noise performance number, finally noise path is removed conversion and return frequency domain, with the channel estimation value after the acquisition noise suppression.

The method that noise window is set according to CP length is: with the time elongatedness of CP length as time delay maximum diameter in system, the position of calculating noise window; Wherein, stipulated the Ts(sampled point of CP under different bandwidth in the LTE system) number N _CP, FFT(Fast Fourier Transformation, fast Fourier transform) and points N _FFT, sub-carrier number N _SC, the time-domain position of time delay maximum diameter can be expressed as:

If adopt IDFT(Inverse Discrete Fourier Transform, inverse discrete Fourier transform) frequency domain is transformed to time domain, the footpath number of time domain channel response is same OFDM(Orthogonal Frequency Division Multiplexing, OFDM) pilot tone point number N on symbol _Pliot, residue footpath number is N _Pliot-N _τ, consider that the signal power leakage can cause afterbody to comprise the problem of available signal power, actual spendable noise path still less, as is got original noise window { N _τ+ 1, N _τ+ 2 ..., N _Pliot-0.5N _τ; If adopt mirror image IDFT that frequency domain is transformed to time domain, the footpath number of mirror image time domain channel response is

The position in useful signal footpath can symmetrical being present in

Scope in, desirable original noise window is

{2N _τ+1，2N _τ+2，…，N _pliot，N _pliot，+2，N _pliot+3，…，2N _pliot+1-2N _τ}

In realizing process of the present invention, the inventor finds in prior art to exist at least following problem:

Support the various bandwidth allocation plan in the LTE system, wherein minimum bandwidth is configured to 1.4MHz, only take 6 PRB (PhVsical Resource Block, Physical Resource Block), because the pilot number on each PRB is consistent, therefore for little bandwidth, its pilot number is relatively less, the amount of information that can use when carrying out channel estimating is less, thereby can cause noise to estimate the measurement result mistake, and channel estimating performance descends.

Concrete, while according to existing mode, carrying out the calculating of original noise window, window is long very little under little bandwidth, and as under the 1.4M bandwidth, this value is If adopt IDFT that frequency domain is transformed to time domain, the footpath number of time domain channel response is 12, residue footpath number is 6, consider the power leakage problem of afterbody useful signal, actual spendable window is long can be still less, if adopt mirror image IDFT that frequency domain is transformed to time domain, the footpath number of mirror image time domain channel response is 24, and the position in useful signal footpath can symmetrical being present in

Scope in, remaining noise path is approximately 1, the footpath number is very few, thereby it is inaccurate to cause noise to be estimated.In addition, under the long time delay scene, the power in useful signal footpath can be leaked to footpath, noise window edge, when window internal diameter number is less, larger on the estimated value impact of noise power, thus the noise suppression effect of Signal estimation is exerted an influence.

Summary of the invention

The embodiment of the present invention provides a kind of acquisition methods and equipment of domain channel response, to improve the performance of channel estimating.In order to achieve the above object, the embodiment of the present invention provides following technical scheme:

The embodiment of the present invention provides a kind of acquisition methods of domain channel response, comprising:

Utilize time domain channel response to calculate the first noise amplitude threshold value g;

Utilize described time domain channel response and described the first noise amplitude threshold value g to calculate the second noise amplitude threshold value G;

Utilize described the second noise amplitude threshold value G to calculate the 3rd noise amplitude threshold value G ';

Utilize the domain channel response after described the 3rd noise amplitude threshold value G ' obtains noise suppression.

The embodiment of the present invention provides a kind of equipment that obtains of domain channel response, comprising:

The first computing module, be used for utilizing time domain channel response to calculate the first noise amplitude threshold value g;

The second computing module, be used for utilizing described time domain channel response and described the first noise amplitude threshold value g to calculate the second noise amplitude threshold value G;

The 3rd computing module, be used for utilizing described the second noise amplitude threshold value G to calculate the 3rd noise amplitude threshold value G ';

Obtain module, be used for utilizing the domain channel response after described the 3rd noise amplitude threshold value G ' obtains noise suppression.

Compared with prior art, the embodiment of the present invention has the following advantages at least: in the embodiment of the present invention, can improve the performance of channel estimating, especially can effectively improve the channel estimating performance under little bandwidth.

Description of drawings

In order to be illustrated more clearly in technical scheme of the present invention, in below describing embodiment, the accompanying drawing of required use is briefly described, 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 channel estimation process schematic diagram of the prior art;

Fig. 2 is the acquisition methods schematic flow sheet of a kind of domain channel response of providing of the embodiment of the present invention one;

Fig. 3 be a kind of domain channel response of providing of the embodiment of the present invention two obtain the device structure schematic diagram.

Embodiment

Below in conjunction with the accompanying drawing in the present invention, the technical scheme in the present invention is clearly and completely described, obviously, described embodiment is only a part of embodiment of the present invention, rather than whole embodiment.Based on the embodiment in the present invention, those of ordinary skills, not making under the creative work prerequisite the every other embodiment that obtains, belong to the scope of protection of the invention.

Embodiment one

The embodiment of the present invention one provides a kind of acquisition methods of domain channel response, and the method can be applied to LTE and LTE-A(LTE-Advanced, senior LTE) etc. system; And the method can be applied to the noise of little bandwidth (being that bandwidth is less than preset bandwidth value) and estimate and channel estimating (namely obtaining domain channel response) process, little bandwidth in the embodiment of the present invention mainly refers to: the time domain footpath number in noise window is less than the band width configuration of a threshold value, and this threshold value can be determined by emulation; And the method can be applied to the up-downgoing channel estimation process simultaneously; As shown in Figure 2, the acquisition methods of this domain channel response comprises the following steps:

Step 201, obtain the time domain channel response of each each frequency pilot sign of port of each reception antenna.

In the embodiment of the present invention, obtain the time domain channel response of each each frequency pilot sign of port of each reception antenna, specifically comprise: the channel estimation in frequency domain value of obtaining pilot frequency locations on each frequency pilot sign of each port of each reception antenna according to following formula:

Adopt IDFT mode or mirror image IDFT mode that the channel estimation in frequency domain value transform of pilot frequency locations on each frequency pilot sign of each port of each reception antenna is arrived time domain, obtain the time domain channel response of each each frequency pilot sign of port of each reception antenna

Wherein, r represents reception antenna, and p represents port, and l represents frequency pilot sign,

The channel estimation in frequency domain value that represents pilot frequency locations on l frequency pilot sign of p port on r reception antenna, For each known pilot frequency sequence,

The reception signal that takes out in the pilot frequency locations of each port for each reception antenna, and

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna.

Further, adopt the IDFT mode with each frequency pilot sign of each port of each reception antenna on the channel estimation in frequency domain value transform of pilot frequency locations in the process of time domain, obtain the time domain channel response of each each frequency pilot sign of port of each reception antenna

Mode for by following formula:

Adopt mirror image IDFT mode with each frequency pilot sign of each port of each reception antenna on the channel estimation in frequency domain value transform of pilot frequency locations in the process of time domain, obtain the time domain channel response of each each frequency pilot sign of port of each reception antenna

Mode for by following formula:

$h_l^{r,p}=\mathrm{IDFT}\left(H^{\′}\right),H^{\′}=\left\{\begin{array}{cc}{H}_l^{r,p}\left(i\right),& i=1,...,N_{\mathrm{pilot}}\\ H_l^{r,p}(2N_{\mathrm{pilot}}+1-i),& i=N_{\mathrm{pilot}}+1,...,2N_{\mathrm{pilot}}\end{array}\right.;$

Wherein, above-mentioned N _PliotFor the footpath number of time domain channel response is pilot tone point number on same orthogonal frequency division multiplex OFDM symbol.

It should be noted that for each frequency pilot sign of each port of each reception antenna, need to carry out respectively follow-up correlation step.

Step 202, utilize time domain channel response to calculate the first noise amplitude threshold value g.

In the embodiment of the present invention, utilize time domain channel response to calculate the process of the first noise amplitude threshold value g, specifically include but not limited to following mode:

Mode one, utilize following formula to calculate the first noise amplitude threshold value g:g=ρ a; Wherein, ρ is weight coefficient, can be determined by emulation, and a is all signal footpath amplitude mean values, and

Mean represents the time domain channel response after taking absolute value

Average.

Mode two, to utilize following formula to calculate the first noise amplitude threshold value g(g this moment be the signal footpath amplitude mean value that improves in noise window):

J={j|j ∈ win}; Wherein, mean represents the time domain channel response after taking absolute value

Average.

Need to prove, the difference that improves noise window and original noise window is, improves in noise window and can comprise part useful signal footpath, and namely the noise window original position need to not be as the criterion with the time delay maximum diameter, but need to as much as possible noise path be included.

In addition, the window method of getting of IDFT mode and mirror image IDFT mode is different, when adopting the IDFT mode to get window, and can be according to win={2N ₁+ 1,2N ₁+ 2 ..., N _Pliot-N ₁Method get window, when adopting mirror image IDFT mode to get window, can be according to win={N ₂+ 1, N ₂+ 2 ..., N _Pliot, N _Pliot+ 2, N _Pliot+ 3 ..., 2N _Pliot+ 1-N ₂Method get window; Wherein, N ₁＜0.5N _τ, N ₂＜2N _τ, value can be determined by emulation, and N _τFor the time-domain position of time delay maximum diameter, N _PliotFor the footpath number of time domain channel response is pilot tone point number on same OFDM symbol.

Step 203, utilize time domain channel response and the first noise amplitude threshold value g to calculate the second noise amplitude threshold value G.

In the embodiment of the present invention, utilize time domain channel response and the first noise amplitude threshold value g to calculate the second noise amplitude threshold value G, comprise: utilize time domain channel response and the first noise amplitude threshold value g calculating noise amplitude mean value, and utilize noise amplitude mean value calculation the second noise amplitude threshold value G.

Utilize time domain channel response and the first noise amplitude threshold value g calculating noise amplitude mean value, comprise: be useful on all the signal footpath amplitudes and the first noise amplitude threshold value g that calculate the first noise amplitude threshold value g are compared, take out the signal footpath of range value lower than the first noise amplitude threshold value g, thereby calculate noise amplitude mean value; Concrete, can utilize following formula calculating noise amplitude mean value

$A_l^{r,p}=\mathrm{mean}\left(\right|h_l^{r,p}\left(k\right)\left|\right),$ And $k=\left\{k\right|\left|h_l^{r,p}\left(k\right)\right|<g\};$ $k=\left\{k\right|\left|h_l^{r,p}\left(k\right)\right|<g\}$ Expression is with the time domain channel response after the taking absolute value of each each frequency pilot sign of port of each reception antenna

All signal footpath amplitudes and the first noise amplitude threshold value g compare, the signal footpath range value of taking-up is lower than the signal footpath of the first noise amplitude threshold value g, mean represents the time domain channel response after taking absolute value

Average.

Utilize noise amplitude mean value calculation the second noise amplitude threshold value G, comprising: utilize following formula to calculate the second noise amplitude threshold value G:

Expression is with the noise amplitude mean value on each frequency pilot sign of each port of each reception antenna

Multiply by 2 after averaging, obtain the second noise amplitude threshold value G.

In the embodiment of the present invention,, based on two noise amplitude threshold value G obtained above, can also carry out noise and estimate, to estimate accurately the noise power under little bandwidth, thereby, according to the noise of noise power-value filtering pilot tone point channel estimating, improve the detection performance.

In the embodiment of the present invention, can take out

In all range values lower than the signal footpath of the second noise amplitude threshold value G as noise path, and calculating noise footpath power average value is the noise power estimation value; Concrete, can utilize following formula calculating noise power estimated value

And $m=\left\{m\right|\left|h_l^{r,p}\left(m\right)\right|<G\};$ $m=\left\{m\right|\left|h_l^{r,p}\left(m\right)\right|<G\}$ Expression is with the time domain channel response after the taking absolute value of each each frequency pilot sign of port of each reception antenna

In all range values lower than the signal footpath of the second noise amplitude threshold value G as noise path, mean represents the time domain channel response after taking absolute value

Square average.

It should be noted that when adopting mirror image IDFT, due to the signal footpath

The range value perseverance be 0, therefore, if adopt mirror image IDFT, also need the signal footpath

Remove.

Step 204, utilize the second noise amplitude threshold value G to calculate the 3rd noise amplitude threshold value G '.

In the embodiment of the present invention, utilize the second noise amplitude threshold value G to calculate the 3rd noise amplitude threshold value G ', comprising: according to following formula, calculate the 3rd noise amplitude threshold value G ': G '=min (λ ₁H _max, λ ₂G); Wherein, min represents to get λ ₁Multiply by h _maxAnd λ ₂Multiply by the little value of the second noise amplitude threshold value G, λ ₁And λ ₂, for default value, can determine by emulation h _maxFor

Each footpath in the maximum of amplitude.

Step 205, utilize the domain channel response after the 3rd noise amplitude threshold value G ' obtains noise suppression.In the embodiment of the present invention, utilize the domain channel response after the 3rd noise amplitude threshold value G ' obtains noise suppression, comprising: determine In all range values higher than the 3rd noise amplitude threshold value G ', and the signal footpath in original noise window is not initial useful signal footpath; Determine that the signal footpath in initial useful signal footpath and its both sides Δ scope is the useful signal footpath, Δ is default value, can determine by emulation; , with other footpath zero setting except the useful signal footpath in all signal footpaths, obtain the time-domain signal response after noise suppression

Time-domain signal response transform after noise suppression to frequency domain, is obtained the domain channel response after noise suppression

Further, in employing IDFT obtains the process of domain channel response, can realize by following formula: In employing mirror image IDFT obtains the process of domain channel response, can realize by following formula: $H^{\&prime;}=\mathrm{DFT}\left({\tilde{h}}_l^{r,p}\right),$ $H_l^{r,p}\left(i\right)=0.5H^{\&prime;}\left(i\right)+0.5H^{\&prime;}({2N}_{\mathrm{pilot}}+1-i).$

In sum, in the embodiment of the present invention, can estimate comparatively accurately the noise power under little bandwidth, improve and detect performance; And can effectively improve channel estimating performance under little bandwidth, especially under the long time delay scene, performance boost is obvious.

Embodiment two

Based on the inventive concept same with said method, a kind of equipment that obtains of domain channel response also is provided in the embodiment of the present invention, as shown in Figure 3, this equipment comprises:

The first computing module 11, be used for utilizing time domain channel response to calculate the first noise amplitude threshold value g;

The second computing module 12, be used for utilizing described time domain channel response and described the first noise amplitude threshold value g to calculate the second noise amplitude threshold value G;

The 3rd computing module 13, be used for utilizing described the second noise amplitude threshold value G to calculate the 3rd noise amplitude threshold value G ';

Obtain module 14, be used for utilizing the domain channel response after described the 3rd noise amplitude threshold value G ' obtains noise suppression.

Described acquisition module 14, also for obtain the channel estimation in frequency domain value of pilot frequency locations on each frequency pilot sign of each port of each reception antenna according to following formula:

Wherein,

The channel estimation in frequency domain value that represents pilot frequency locations on l frequency pilot sign of p port on r reception antenna,

For known pilot frequency sequence,

The reception signal that takes out in the pilot frequency locations of each port for each reception antenna;

Adopt inverse discrete Fourier transform IDFT mode or mirror image IDFT mode that the channel estimation in frequency domain value transform of pilot frequency locations on each frequency pilot sign of each port of each reception antenna is arrived time domain, obtain the time domain channel response of each each frequency pilot sign of port of each reception antenna

Described the first computing module 11, concrete for utilizing following formula to calculate the first noise amplitude threshold value g:g=ρ a; Wherein, ρ is weight coefficient, The time domain channel response that represents l frequency pilot sign of p port on r reception antenna, mean represent the time domain channel response after taking absolute value Average; Perhaps,

Utilize following formula to calculate the first noise amplitude threshold value g: J={j|j ∈ win}; Wherein,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna, mean represent the time domain channel response after taking absolute value Average; When adopting the IDFT mode to get window, win={2N ₁+ 1,2N ₁+ 2 ..., N _Pliot-N ₁, when adopting mirror image IDFT mode to get window, win={N ₂+ 1, N ₂+ 2 ..., N _Pliot, N _Pliot+ 2, N _Pliot+ 3 ..., 2N _Pliot+ 1-N ₂; And N ₁＜0.5N _τ, N ₂＜2N _τ, and N _τFor the time-domain position of time delay maximum diameter, N _PliotFor the footpath number of time domain channel response is pilot tone point number on same orthogonal frequency division multiplex OFDM symbol.

Described the second computing module 12, concrete being used for utilized described time domain channel response and described the first noise amplitude threshold value g calculating noise amplitude mean value, and utilizes described the second noise amplitude threshold value G of described noise amplitude mean value calculation.

Described the second computing module 12, be further used for utilizing following formula to calculate described noise amplitude mean value

And

Wherein,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna,

Expression is with the time domain channel response after the taking absolute value of each each frequency pilot sign of port of each reception antenna

All signal footpath amplitudes and the first noise amplitude threshold value g compare, the signal footpath range value of taking-up is lower than the signal footpath of the first noise amplitude threshold value g, mean represents the time domain channel response after taking absolute value

Average.

Described the second computing module 12 is further used for utilizing following formula to calculate described the second noise amplitude threshold value G:

Its expression is with the noise amplitude mean value on each frequency pilot sign of each port of each reception antenna

Multiply by 2 after averaging, obtain described the second noise amplitude threshold value G.

This equipment also comprises: the 4th computing module 15 is used for utilizing following formula calculating noise power estimated value

${\left({\mathrm{\&sigma;}}_l^{r,p}\right)}^2=\mathrm{mean}\left({\left|h_l^{r,p}\left(m\right)\right|}^2\right),$ And $m=\left\{m\right|\left|h_l^{r,p}\left(m\right)\right|<G\};$ Wherein,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna,

Expression is with the time domain channel response after the taking absolute value of each each frequency pilot sign of port of each reception antenna

In all range values lower than the signal footpath of the second noise amplitude threshold value G as noise path, mean represents the time domain channel response after taking absolute value

Square average.

Described the 3rd computing module 13, concrete being used for calculated the 3rd noise amplitude threshold value G ' according to following formula: Wherein, min represents to get λ ₁Multiply by h _maxAnd λ ₂Multiply by the little value of the second noise amplitude threshold value G, γ ₁And λ ₂For default value, h _maxFor

Each footpath in the maximum of amplitude,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna.

Described acquisition module 14, concrete being used for determined In all range values higher than the 3rd noise amplitude threshold value G ', and the signal footpath in original noise window is not initial useful signal footpath, and is described

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna; Determine that the signal footpath in described initial useful signal footpath and its both sides Δ scope is the useful signal footpath, described Δ is default value; , with other footpath zero setting except described useful signal footpath in all signal footpaths, obtain the time-domain signal response after noise suppression; Time-domain signal response transform after described noise suppression to frequency domain, is obtained the domain channel response after noise suppression.

Wherein, the modules of apparatus of the present invention can be integrated in one, and also can separate deployment.Above-mentioned module can be merged into a module, also can further split into a plurality of submodules.

Through the above description of the embodiments, those skilled in the art can be well understood to the present invention and can realize by the mode that software adds essential general hardware platform, 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 a storage medium, comprise that some instructions are with so that a computer equipment (can be personal computer, server, the perhaps network equipment etc.) carry out the described method of each embodiment of the present invention.

It will be appreciated by those skilled in the art that accompanying drawing is the schematic diagram of a preferred embodiment, the module in accompanying drawing or flow process might not be that enforcement the present invention is necessary.

It will be appreciated by those skilled in the art that the module in the device in embodiment can be distributed in the device of embodiment according to the embodiment description, also can carry out respective change and be arranged in the one or more devices that are different from the present embodiment.The module of above-described embodiment can be merged into a module, also can further split into a plurality of submodules.

The invention described above embodiment sequence number, just to describing, does not represent the quality of embodiment.

Above disclosed be only several specific embodiment of the present invention, still, the present invention is not limited thereto, the changes that any person skilled in the art can think of all should fall into protection scope of the present invention.

Claims (18)

1. the acquisition methods of a domain channel response, is characterized in that, comprising:

Utilize time domain channel response to calculate the first noise amplitude threshold value g;

Utilize described time domain channel response and described the first noise amplitude threshold value g to calculate the second noise amplitude threshold value G;

Utilize described the second noise amplitude threshold value G to calculate the 3rd noise amplitude threshold value G ';

Utilize the domain channel response after described the 3rd noise amplitude threshold value G ' obtains noise suppression.

2. the method for claim 1, is characterized in that, the described time domain channel response that utilizes calculates the first noise amplitude threshold value g, also comprises before:

Obtain the channel estimation in frequency domain value of pilot frequency locations on each frequency pilot sign of each port of each reception antenna according to following formula:

Wherein,

The channel estimation in frequency domain value that represents pilot frequency locations on l frequency pilot sign of p port on r reception antenna,

For known pilot frequency sequence, The reception signal that takes out in the pilot frequency locations of each port for each reception antenna;

Adopt inverse discrete Fourier transform IDFT mode or mirror image IDFT mode that the channel estimation in frequency domain value transform of pilot frequency locations on each frequency pilot sign of each port of each reception antenna is arrived time domain, obtain the time domain channel response of each each frequency pilot sign of port of each reception antenna

3. the method for claim 1, is characterized in that, the described time domain channel response that utilizes calculates the first noise amplitude threshold value g, comprising:

Utilize following formula to calculate the first noise amplitude threshold value g:g=ρ a; Wherein, ρ is weight coefficient,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna, mean represent the time domain channel response after taking absolute value

Average; Perhaps,

Utilize following formula to calculate the first noise amplitude threshold value g:

J={j|j ∈ win}; Wherein, The time domain channel response that represents l frequency pilot sign of p port on r reception antenna, mean represent the time domain channel response after taking absolute value

Average; When adopting the IDFT mode to get window, win={2N ₁+ 1,2N ₁+ 2 ..., N _Pliot-N ₁, when adopting mirror image IDFT mode to get window, win={N ₂+ 1, N ₂+ 2 ..., N _Plion, N _Pliot+ 2, N _Pliot+ 3 ..., 2N _Pliot+ 1-N ₂; And N ₁＜0.5N _τ, N ₂＜2N _τ, and N _τFor the time-domain position of time delay maximum diameter, N _PliotFor the footpath number of time domain channel response is pilot tone point number on same orthogonal frequency division multiplex OFDM symbol.

4. the method for claim 1, is characterized in that, utilizes described time domain channel response and described the first noise amplitude threshold value g to calculate the second noise amplitude threshold value G, comprising:

Utilize described time domain channel response and described the first noise amplitude threshold value g calculating noise amplitude mean value, and utilize described the second noise amplitude threshold value G of described noise amplitude mean value calculation.

5. method as claimed in claim 4, is characterized in that, utilizes described time domain channel response and described the first noise amplitude threshold value g calculating noise amplitude mean value, comprising:

Utilize following formula to calculate described noise amplitude mean value

And

Wherein,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna,

Expression is with the time domain channel response after the taking absolute value of each each frequency pilot sign of port of each reception antenna

All signal footpath amplitudes and the first noise amplitude threshold value g compare, the signal footpath range value of taking-up is lower than the signal footpath of the first noise amplitude threshold value g, mean represents the time domain channel response after taking absolute value

Average.

6. method as claimed in claim 4, is characterized in that, utilizes described the second noise amplitude threshold value G of described noise amplitude mean value calculation, comprising:

Utilize following formula to calculate described the second noise amplitude threshold value G:

Its expression is with the noise amplitude mean value on each frequency pilot sign of each port of each reception antenna

Multiply by 2 after averaging, obtain described the second noise amplitude threshold value G.

7. the method for claim 1, is characterized in that, utilizes described time domain channel response and described the first noise amplitude threshold value g to calculate the second noise amplitude threshold value G, also comprises afterwards:

Utilize following formula calculating noise power estimated value

And

Wherein, The time domain channel response that represents l frequency pilot sign of p port on r reception antenna, Expression is with the time domain channel response after the taking absolute value of each each frequency pilot sign of port of each reception antenna

In all range values lower than the signal footpath of the second noise amplitude threshold value G as noise path, mean represents the time domain channel response after taking absolute value

Square average.

8. the method for claim 1, is characterized in that, utilizes described the second noise amplitude threshold value G to calculate the 3rd noise amplitude threshold value G ', comprising:

Calculate the 3rd noise amplitude threshold value G ': G '=min (λ according to following formula ₁H _max, λ ₂G); Wherein, min represents to get λ ₁Multiply by h _maxAnd λ ₂Multiply by the little value of the second noise amplitude threshold value G, λ ₁And λ ₂For default value, h _maxFor

Each footpath in the maximum of amplitude,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna.

9. the method for claim 1, is characterized in that, utilizes the domain channel response after described the 3rd noise amplitude threshold value G ' obtains noise suppression, comprising:

Determine

In all range values higher than the 3rd noise amplitude threshold value G ', and the signal footpath in original noise window is not initial useful signal footpath, and is described

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna;

Determine that the signal footpath in described initial useful signal footpath and its both sides Δ scope is the useful signal footpath, described Δ is default value;

, with other footpath zero setting except described useful signal footpath in all signal footpaths, obtain the time-domain signal response after noise suppression;

Time-domain signal response transform after described noise suppression to frequency domain, is obtained the domain channel response after noise suppression.

10. the equipment that obtains of a domain channel response, is characterized in that, comprising:

The first computing module, be used for utilizing time domain channel response to calculate the first noise amplitude threshold value g;

The second computing module, be used for utilizing described time domain channel response and described the first noise amplitude threshold value g to calculate the second noise amplitude threshold value G;

The 3rd computing module, be used for utilizing described the second noise amplitude threshold value G to calculate the 3rd noise amplitude threshold value G ';

Obtain module, be used for utilizing the domain channel response after described the 3rd noise amplitude threshold value G ' obtains noise suppression.

11. equipment as claimed in claim 10, is characterized in that,

Described acquisition module, also for obtain the channel estimation in frequency domain value of pilot frequency locations on each frequency pilot sign of each port of each reception antenna according to following formula:

Wherein, The channel estimation in frequency domain value that represents pilot frequency locations on l frequency pilot sign of p port on r reception antenna,

For known pilot frequency sequence,

The reception signal that takes out in the pilot frequency locations of each port for each reception antenna;

Adopt inverse discrete Fourier transform IDFT mode or mirror image IDFT mode that the channel estimation in frequency domain value transform of pilot frequency locations on each frequency pilot sign of each port of each reception antenna is arrived time domain, obtain the time domain channel response of each each frequency pilot sign of port of each reception antenna

12. equipment as claimed in claim 10, is characterized in that,

Described the first computing module, concrete for utilizing following formula to calculate the first noise amplitude threshold value g:g=ρ a; Wherein, ρ is weight coefficient,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna, mean represent the time domain channel response after taking absolute value

Average; Perhaps,

Utilize following formula to calculate the first noise amplitude threshold value g:

J={j|j ∈ win}; Wherein,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna, mean represent the time domain channel response after taking absolute value

Average; When adopting the IDFT mode to get window, win={2N ₁+ 1,2N ₁+ 2 ..., N _Pliot-N ₁, when adopting mirror image IDFT mode to get window, win={N ₂+ 1, N ₂+ 2 ..., N _Pliot, N _Pliot+ 2, N _Pliot+ 3 ..., 2N _Pliot+ 1-N ₂; And N ₁＜0.5N _τ, N ₂＜2N _τ, and N _τFor the time-domain position of time delay maximum diameter, N _PliotFor the footpath number of time domain channel response is pilot tone point number on same orthogonal frequency division multiplex OFDM symbol.

13. equipment as claimed in claim 10, is characterized in that,

Described the second computing module, concrete being used for utilized described time domain channel response and described the first noise amplitude threshold value g calculating noise amplitude mean value, and utilizes described the second noise amplitude threshold value G of described noise amplitude mean value calculation.

14. equipment as claimed in claim 13, is characterized in that,

Described the second computing module, be further used for utilizing following formula to calculate described noise amplitude mean value

And

Wherein,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna,

Expression is with the time domain channel response after the taking absolute value of each each frequency pilot sign of port of each reception antenna

All signal footpath amplitudes and the first noise amplitude threshold value g compare, the signal footpath range value of taking-up is lower than the signal footpath of the first noise amplitude threshold value g, mean represents the time domain channel response after taking absolute value

Average.

15. equipment as claimed in claim 13, is characterized in that,

Described the second computing module is further used for utilizing following formula to calculate described the second noise amplitude threshold value G: Its expression is with the noise amplitude mean value on each frequency pilot sign of each port of each reception antenna

Multiply by 2 after averaging, obtain described the second noise amplitude threshold value G.

16. equipment as claimed in claim 10, is characterized in that, also comprises:

The 4th computing module, be used for utilizing following formula calculating noise power estimated value

And

Wherein,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna,

Expression is with the time domain channel response after the taking absolute value of each each frequency pilot sign of port of each reception antenna

In all range values lower than the signal footpath of the second noise amplitude threshold value G as noise path, mean represents the time domain channel response after taking absolute value

Square average.

17. equipment as claimed in claim 10, is characterized in that,

Described the 3rd computing module, concrete being used for calculated the 3rd noise amplitude threshold value G ' according to following formula:

Wherein, min represents to get λ ₁Multiply by h _maxAnd λ ₂Multiply by the little value of the second noise amplitude threshold value G, λ ₁And λ ₂For default value, h _maxFor

Each footpath in the maximum of amplitude,

The time domain channel response that represents l frequency pilot sign of p port on r reception antenna.

18. equipment as claimed in claim 10, is characterized in that,

Described acquisition module, concrete being used for determined

In all range values higher than the 3rd noise amplitude threshold value G ', and the signal footpath in original noise window is not initial useful signal footpath, and is described The time domain channel response that represents l frequency pilot sign of p port on r reception antenna;

Determine that the signal footpath in described initial useful signal footpath and its both sides Δ scope is the useful signal footpath, described Δ is default value;

, with other footpath zero setting except described useful signal footpath in all signal footpaths, obtain the time-domain signal response after noise suppression;

Time-domain signal response transform after described noise suppression to frequency domain, is obtained the domain channel response after noise suppression.

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