CN102480314A - Self-adaptive method and device for eliminating interference of multiple antennae through diversity and mergence - Google Patents

Abstract

The invention discloses a self-adaptive method and device for eliminating interference of multiple antennae through diversity and mergence. The method comprises the following steps of: measuring noise power of each receiving antenna; judging whether the ratio of the sum of diagonal elements of an NI (Noise Index) matrix of a data carrier to be detected to an average value of the noise power of all receiving antennae is larger than a preset threshold value; if so, carrying out interference suppression and mergence detection on the data carrier to be detected; and if not, carrying out noninterference suppression and mergence detection on the data carrier to be detected. Starting from an NI estimation matrix as the most fundamental factor influencing an IRC (Interference Rejection Combining) merging algorithm, whether the currently obtained NI matrix contains more interference components is judged through the specific numerical value characteristic of the NI matrix, and then, an IRC algorithm or MRC (Mixed Radix Conversion) algorithm is selected, so that the system obtains the optimal performance.

Description

A kind of self-adaptive multi antenna diversity merges interference elimination method and device

Technical field

The present invention relates to the mobile communication technology field, more specifically, relate to a kind of self-adaptive multi antenna diversity and merge interference elimination method and device.

Background technology

Wireless communication system always receives various interference; For with OFDMA (Orthogonal Frequency Division Multiple Access; The OFDM access) technology is the 4th generation communication (4G) system on basis, like Wimax (Worldwide Interoperability for Microwave Access, worldwide interoperability for microwave inserts); LTE (Long Term Evolution; Long Term Evolution), receive more serious OFDM co-channel interference (Co-Channel Interference abbreviates CCI as) all the time.In cellular network, because the relation of spectrum reuse, this kind interference shows as the adjacent area and disturbs, because interference source disturbs a plurality of data carriers usually, thereby can think a kind of interference of broadband.

At present, adjacent area Interference Control/inhibition/elimination problem is studying a question of a hot topic, also is the problem that 4G communication system identical networking must solve.Wave beam forming/scheduling that active means show as power control, dynamic channeling, adjacent area is usually cooperated and just in question CoMP (Coordinated Multipoint transmission/reception; Multipoint cooperative transmission reception) joint transmission in; These technology just need be done more detailed discussion when standard formulation, need network configuration and signaling support.Interference cancellation techniques at passive type does not then rely on the mutual of signaling, is accomplished by receiver usually, can be in diverse network.

Usually in fact; The interference eliminated of receiver side often will depend on the resource of space, time and three dimensions of frequency; Consider the 4th generation communication system extensively adopted multi-antenna technology (MIMO), adopted widely by mimo system carrying out the set of the branch of the signal response sample on a plurality of antennas on the Spatial Dimension and receive.Traditional multi-antenna diversity merge algorithm has equal gain combining; Selectivity merges and high specific merges (Maximum Ratio Combining; Abbreviate MRC as) etc.; Very outstanding performance is arranged under the channel circumstance of noise limited, but performance is unsatisfactory under interference-limited channel circumstance, simultaneously one type is that the multi-antenna diversity merge algorithm of main purpose is called as to disturb and suppresses folding (Interference Rejection Combining to suppress to disturb; Abbreviate IRC as), eliminating the adjacent area with having embodied excellent performance in the interference frequently.But the complexity of IRC algorithm is higher than MRC algorithm, and under the scene of noise limited, does not have advantage even mis-behave to a certain degree can occur compared to the MRC algorithm.

At present, result of the above problems is that the self adaptation of carrying out IRC algorithm and MRC algorithm is switched, and under interference-limited scene, carries out IRC and merges, and under the scene of noise limited, carries out MRC and merges.

Compare with traditional MRC merge algorithm, the core concept of IRC algorithm is to disturb and the estimation of noise correlation matrix (NI matrix), uses NI inverse of a matrix matrix to handle the reception signal, suppresses interference components, the stick signal component.Thereby when reality is used the IRC algorithm, can obtain more accurately that the NI Matrix Estimation is a key factor, and it is obvious more to that is to say that the characteristic disturbed in the NI matrix embodies, and the performance of IRC merge algorithm is good more.

Mainly have following technical problem in the prior art: interference in general sense suppresses to merge the self adaptation handoff technique that suppresses merging with non-interference; Be to adjudicate to receive in the signal through the signal characteristic of receiver side to have or not interfering components, and then select to divide set and algorithm.But when reality is used, often exist to receive and have very big interfering components in the signal, but the interference components that comprises in the NI matrix is less or do not have, use the IRC algorithm can make mis-behave on the contrary this moment.This is because participate in the sample size of statistical computation NI matrix when not enough (being generally the number of pilots in certain resource granularity); The calculated value of NI matrix can't react the characteristic of interference; Estimate that the main component of the NI matrix of acquisition is a noise, can't embody the spatial correlation characteristic of interference channel, in this case this moment; Owing to can't obtain the characteristic of interference signal, can only select the merge algorithm (MRC) that uses non-interference to suppress.

Summary of the invention

The technical problem that the present invention solves provides a kind of self-adaptive multi antenna diversity and merges interference elimination method and device, can between interference suppression algorithm (IRC) and non-interference suppression algorithm (MRC), switch adaptively.

For solving the problems of the technologies described above, the invention provides a kind of self-adaptive multi antenna diversity and merge interference elimination method, comprising:

Measure the noise power on the every reception antenna;

Whether the ratio of average of diagonal entry sum and the noise power on each reception antenna of interference noise covariance matrix (NI matrix) of judging the data to be tested carrier wave is greater than predetermined threshold value; If then said data to be tested carrier wave is disturbed to suppress to merge and detects; Otherwise, said data to be tested carrier wave is carried out non-interference suppresses to merge detection.

Further, said method also comprises:

Draw the channel response estimated value of each data carrier on the Resource Block through channel estimating;

And estimate the estimated value of the NI matrix of each data carrier according to said channel response estimated value.

Further, measure the noise power on said each reception antenna through the mode of unloaded ripple or quiet frame.

Further, disturb inhibition to merge to said data to be tested carrier wave and detect, specifically comprise:

Calculate the NI inverse of a matrix matrix of said data to be tested carrier wave, and calculate merging back symbol according to following formula:

${\hat{S}}_i=H_i^H\·{\left(R_i\right)}^{-1}\·y_i;$

Wherein,

Be i the data carrier symbol after the merging, R _iBe the NI Matrix Estimation value of i data carrier, y _iThe column vector that constitutes for the response of i data carrier on each reception antenna,

Column vector for each reception antenna channel response estimated value formation.

Further, said data to be tested carrier wave is carried out non-interference suppresses to merge detection, specifically comprise:

Calculate merging back symbol according to following formula:

The present invention also provides a kind of self-adaptive multi antenna diversity to merge interference blanking unit, and said device comprises:

The antenna noise measurement module is used to measure the noise power on the every reception antenna;

The self-adaptive decision module, whether the ratio of average of diagonal entry sum and the noise power on each reception antenna of NI matrix of data to be tested carrier wave that is used to judge estimation is greater than predetermined threshold value;

Merge processing module, be used for court verdict, if court verdict is for being then said data to be tested carrier wave to be disturbed and suppress to merge detection according to said self-adaptive decision module; Otherwise, said data to be tested carrier wave is carried out non-interference suppresses to merge detection.

Further, said device also comprises:

Channel estimation module is used for drawing through channel estimating the channel response estimated value of each data carrier on the Resource Block;

The NI matrix estimation module, the said channel response estimated value that is used for drawing according to said channel estimation module is estimated the estimated value of the NI matrix of each data carrier.

Further, said antenna noise measurement module is used for, and measures the noise power on said each reception antenna through the mode of unloaded ripple or quiet frame.

Further, said merging processing module is used for, and when disturbing inhibition to merge detection to said data to be tested carrier wave, specifically comprises:

Calculate the NI inverse of a matrix matrix of said data to be tested carrier wave, and calculate merging back symbol according to following formula:

${\hat{S}}_i=H_i^H\·{\left(R_i\right)}^{-1}\·y_i;$

Wherein,

Be i the data carrier symbol after the merging, R _iBe the NI Matrix Estimation value of i data carrier, y _iThe column vector that constitutes for the response of i data carrier on each reception antenna,

Column vector for each reception antenna channel response estimated value formation.

Further, said merging processing module is used for, and said data to be tested carrier wave is carried out non-interference suppress to merge when detecting, and specifically comprises:

Calculate merging back symbol according to following formula:

The present invention starts with from the basic factor NI estimated matrix that influences the IRC merge algorithm; Whether the NI matrix of judging current acquisition through the special value characteristic of NI matrix comprises more interfering components; And then select to use the IRC algorithm still be the MRC algorithm, makes system obtain the performance of optimum.

Adopt the present invention, when existing serious adjacent area to disturb, can suppress this interference significantly with frequency; Simultaneously, in the time of a little less than not existing with interference frequently or disturbing very together frequently, still can obtain sane performance, the deterioration of performance can not occur; And,, still can obtain sane performance, and can reduce in such cases complexity and operand the NI Matrix Estimation occurring when inaccurate.

Description of drawings

Fig. 1 is the schematic flow sheet according to the self-adaptive multi antenna diversity merging method of the embodiment of the invention.

Embodiment

Of the present inventionly mainly be contemplated that: at first, estimate the noise power on the every antenna; Secondly, the make an uproar average of power of the end of a plurality of reception antennas is compared with the diagonal entry of the NI matrix of estimation, rule out whether comprise more interfering components in the NI matrix, and then whether decision carries out matrix inversion and other computings; At last, carry out respective diversity and merge processing.

Based on above design, the present invention provides a kind of self-adaptive multi antenna diversity to merge interference elimination method, specifically adopts following technical scheme:

Measure the noise power on the every reception antenna;

Whether the ratio of the diagonal entry sum of the NI matrix of the data to be tested carrier wave that judgement is estimated and the average of the noise power on each reception antenna is greater than predetermined threshold value, if then said data to be tested carrier wave is carried out IRC and detect; Otherwise, said data to be tested carrier wave is carried out MRC merges detection.

Further, said method also comprises:

Draw the channel response estimated value of each data carrier on the Resource Block through channel estimating;

And estimate the interference noise covariance matrix (NI matrix) of each data carrier according to said channel response estimated value.

Further, the measurement of the noise power on the said reception antenna includes but not limited to following mode:

A) mode of unloaded ripple, the noise power of promptly utilizing the unloaded ripple that does not send any data to carry out on the said reception antenna is estimated;

B) mode of quiet frame, this base station of promptly a certain frame notifies the user not launch any signal, and this moment, base station side just can be measured the power of making an uproar at the bottom of the antenna.

Further, said data to be tested carrier wave is carried out IRC detects, specifically comprise:

Calculate the NI inverse of a matrix matrix of said data to be tested carrier wave, and calculate merging back symbol according to following formula:

${\hat{S}}_i=H_i^H\·{\left(R_i\right)}^{-1}\·y_i;$

Wherein,

Be i the data carrier symbol after the merging, R _iBe the NI matrix on i the carrier wave, y _iThe column vector that constitutes for the response of i carrier wave on each reception antenna,

Column vector for each antenna channel estimated result formation.

Further, said data to be tested carrier wave is carried out IRC detects, specifically comprise:

Calculate merging back symbol according to following formula:

For the ease of setting forth the present invention, the present invention is described further below with reference to accompanying drawing and specific embodiment.

Fig. 1 shows the schematic flow sheet of the self-adaptive multi antenna diversity merging method of the embodiment of the invention, and is as shown in Figure 1, and this flow process mainly may further comprise the steps:

Step 110, the noise power σ on the every reception antenna is measured in the estimation of making an uproar at the bottom of the unloaded wave antenna _j, wherein j representes j root reception antenna;

Step 120; Through channel estimating, wherein i, j represent i carrier wave in the j root reception antenna to draw the channel response estimated value

of p data carrier on the Resource Block to be detected;

Particularly, can adopt sequence correlated channels method of estimation, promptly utilize the correlation properties between the different sequences that different base station sends to suppress to disturb.

Step 130, the NI Matrix Estimation obtains the estimated value R of the interference noise covariance matrix NI of each data carrier on the Resource Block to be detected _i,

Wherein, R _iBe the NI Matrix Estimation value on i the data carrier, R _iDimension be [reception antenna is counted * reception antenna number];

Wherein, estimate that the purpose of NI matrix is to use NI inverse of a matrix matrix as a part of handling weights, use these processing weights to suppress to disturb.

Step 140, self-adaptive decision judges whether following formula is set up, if set up, then changes step 150 over to; Otherwise change step 160 over to,

$\frac{\mathrm{Trace}\left(R_i\right)}{\frac{1}{m}\underset{j=1}{\overset{m}{\mathrm{\Σ}}}{\mathrm{\σ}}_j}\≥\mathrm{\α}$

Wherein, Trace (A) expression A matrix trace, be its diagonal entry with.The make an uproar average of power of the end of

expression m root reception antenna.α is constant for predetermined judging threshold.The jitter problem of the diagonal entry of NI matrix when considering practical application, preferred, get α=1.5.

Step 150 is carried out the IRC detection according to R and channel estimation results, selects a carrier wave in the pending Resource Block, calculates current carrier wave NI inverse of a matrix matrix (R ⁱ) ^-1, and calculate according to following formula and to merge the back symbol:

${\hat{S}}_i=H_i^H\·{\left(R_i\right)}^{-1}\·y_i;$

Wherein,

Be i the data carrier symbol after the merging, R _iBe the estimated value of NI matrix, y _iThe column vector that constitutes for the response of i carrier wave on each reception antenna, Be each antenna channel estimated result The column vector that constitutes.

Step 160 is carried out data carrier MRC and is merged detection, calculates according to following formula to merge the back symbol:

${\hat{S}}_i=H_i^H\·y_i.$

After accomplishing above-mentioned steps 150 or step 160, finish this algorithm, reselect next carrier wave symbol to be detected and repeat above step.

Below with reference to some applying examples the enforcement of technical scheme of the present invention is done further to describe in detail.

Applying examples one

Should use in the example, suppose that certain communication system receiver side has m root reception antenna, obtain m during reception and received sample of signal S ¹S ²... S ^m

Suppose that there be n Resource Block to be detected in this system, has p data to be tested carrier wave and q pilot frequency carrier wave in each Resource Block.

At first, use the unloaded ripple that does not send any data to carry out the estimation of making an uproar at the bottom of the antenna, the power of making an uproar at the bottom of the measurement acquisition m root reception antenna is σ ₁σ ₂σ _m

Select a Resource Block to be detected; Estimate the channel response on the every reception antenna; Utilize q pilot frequency carrier wave on it to carry out channel estimating, wherein i, j represent i carrier wave in the j root reception antenna to the channel response estimated value

of p data carrier of acquisition.

Select above-mentioned Resource Block to be detected, accomplish the NI Matrix Estimation value R of p data carrier _i, wherein Ri representes i data carrier.

Select a data to be tested carrier wave, according to its NI matrix of following formula judgement R _i:

$\frac{\mathrm{Trace}\left(R_i\right)}{\frac{1}{m}\underset{j=1}{\overset{m}{\mathrm{\Σ}}}{\mathrm{\σ}}_j}\≥\mathrm{\α};$

Wherein, Trace (A) expression A matrix trace is R _iDiagonal entry with;

The make an uproar average of power of the end of expression m root reception antenna.

Suppose and to use in the example, satisfy above-mentioned inequality, judge R _iWhether matrix is reversible, if reversible its inverse matrix of then calculating, and calculates according to following formula and to merge the back symbol:

${\hat{S}}_i=H_i^H\·{\left(R_i\right)}^{-1}\·y_i;$

If R ⁱMatrix is irreversible, then can solve through the diagonal angle load mode.

Finish this algorithm after accomplishing, reselect next carrier wave symbol to be detected and repeat above-mentioned decision steps.After the detection of accomplishing these all carrier waves of Resource Block merges, select next Resource Block to be detected, repeat above-mentioned algorithm, all accomplish detection until all Resource Block to be detected.

Applying examples two

Suppose that certain communication system receiver side has m root reception antenna, obtained m during reception and received sample of signal S ¹S ²... S ^m

Suppose that there be n Resource Block to be detected in this system, has p data to be tested carrier wave and q pilot frequency carrier wave in each Resource Block.

At first, use the unloaded ripple that does not send any data to carry out the estimation of making an uproar at the bottom of the antenna, the power of making an uproar at the bottom of the measurement acquisition m root reception antenna is σ ₁σ ₂σ _m

Select a Resource Block to be detected; Estimate the channel response on the every reception antenna; Utilize q pilot frequency carrier wave on it to carry out channel estimating, wherein i, j represent i carrier wave in the j root reception antenna to the channel response estimated value

of p data carrier of acquisition.

Select above-mentioned Resource Block to be detected, accomplish the NI Matrix Estimation R of p data carrier _i, R wherein _iRepresent i data carrier.

Select a data to be tested carrier wave, according to its NI matrix of following formula judgement R _i:

$\frac{\mathrm{Trace}\left(R_i\right)}{\frac{1}{m}\underset{j=1}{\overset{m}{\mathrm{\Σ}}}{\mathrm{\σ}}_j}\≥\mathrm{\α};$

Wherein, Trace (A) expression A matrix trace is R _iDiagonal entry with;

The make an uproar average of power of the end of expression m root reception antenna.

Suppose and should then from current Resource Block, select a data to be tested carrier wave, use following formula to obtain final the detection and merge symbol with not satisfying above-mentioned inequality in the example:

${\hat{S}}_i=H_i^H\·y_i.$

Finish this algorithm after accomplishing, reselect next carrier wave symbol to be detected and repeat above-mentioned decision steps.After the detection of accomplishing these all carrier waves of Resource Block merges, select next Resource Block to be detected, repeat above-mentioned algorithm, all accomplish detection until all Resource Block to be detected.

According to above description; Adopt the present invention whether to have interference by the current channel circumstance of adaptive judgement; And when having interference; Whether embodied the characteristic of disturbing in the interference noise covariance matrix of current estimation, and then adaptive switching between interference suppression algorithm (IRC) and non-interference suppression algorithm (MRC).

Accordingly, the embodiment of the invention also provides a kind of self-adaptive multi antenna diversity to merge interference blanking unit, and branch set and interference blanking unit as complete need comprise channel estimating, and correlation modules such as NI Matrix Estimation and branch set and calculating are as support.In the present embodiment, this device mainly comprises following functional module:

The antenna noise measurement module is used to measure the noise power on the every reception antenna;

The self-adaptive decision module, whether the ratio of average of diagonal entry sum and the noise power on each reception antenna of NI matrix of data to be tested carrier wave that is used to judge estimation is greater than predetermined threshold value;

Merge processing module, be used for court verdict, if court verdict is for being then said data to be tested carrier wave to be disturbed and suppress to merge detection according to said self-adaptive decision module; Otherwise, said data to be tested carrier wave is carried out non-interference suppresses to merge detection.

Further, said device also comprises: channel estimation module and NI matrix estimation module,

Channel estimation module is used for, and draws the channel response estimated value of each data carrier on the Resource Block through channel estimating;

The NI matrix estimation module is used for, and the said channel response estimated value that draws according to said channel estimation module is estimated the estimated value of the NI matrix of each data carrier.

Further, said antenna noise measurement module is used for, and measures the noise power on said each reception antenna through the mode of unloaded ripple or quiet frame.

Further, said merging processing module is used for, and when disturbing inhibition to merge detection to said data to be tested carrier wave, specifically comprises:

Calculate the NI inverse of a matrix matrix of said data to be tested carrier wave, and calculate merging back symbol according to following formula:

${\hat{S}}_i=H_i^H\·{\left(R_i\right)}^{-1}\·y_i;$

Wherein, Be i the data carrier symbol after the merging, R _iBe the NI Matrix Estimation value of i data carrier, y _iThe column vector that constitutes for the response of i data carrier on each reception antenna,

Column vector for each reception antenna channel response estimated value formation.

Further, said merging processing module is used for, and said data to be tested carrier wave is carried out non-interference suppress to merge when detecting, and specifically comprises:

Calculate merging back symbol according to following formula:

More than be merely preferred case study on implementation of the present invention; Be not limited to the present invention; The present invention also can have other various embodiments; Under the situation that does not deviate from spirit of the present invention and essence thereof, those of ordinary skill in the art can make various corresponding changes and distortion according to the present invention, but these corresponding changes and distortion all should belong to the protection range of the appended claim of the present invention.

Obviously, it is apparent to those skilled in the art that above-mentioned each functional module of the present invention or each step can realize with the general calculation device; They can concentrate on the single calculation element; Perhaps be distributed on the network that a plurality of calculation element forms, alternatively, they can be realized with the executable program code of calculation element; Thereby; Can they be stored in the storage device and carry out, and in some cases, can carry out step shown or that describe with the order that is different from here by calculation element; Perhaps they are made into each integrate circuit function module respectively, perhaps a plurality of functional modules in them or step are made into the single integrated circuit functional module and realize.Like this, the present invention is not restricted to any specific hardware and software combination.

Claims (10)

1. a self-adaptive multi antenna diversity merges interference elimination method, it is characterized in that, comprising:

Measure the noise power on the every reception antenna;

Whether the ratio of average of diagonal entry sum and the noise power on each reception antenna of interference noise covariance matrix (NI matrix) of judging the data to be tested carrier wave is greater than predetermined threshold value; If then said data to be tested carrier wave is disturbed to suppress to merge and detects; Otherwise, said data to be tested carrier wave is carried out non-interference suppresses to merge detection.

2. the method for claim 1 is characterized in that, said method also comprises:

Draw the channel response estimated value of each data carrier on the Resource Block through channel estimating;

And estimate the estimated value of the NI matrix of each data carrier according to said channel response estimated value.

3. the method for claim 1 is characterized in that,

Measure the noise power on said each reception antenna through the mode of unloaded ripple or quiet frame.

4. like claim 1,2 or 3 described methods, it is characterized in that, said data to be tested carrier wave disturbed to suppress to merge detect, specifically comprise:

Calculate the NI inverse of a matrix matrix of said data to be tested carrier wave, and calculate merging back symbol according to following formula:

${\hat{S}}_i=H_i^H\·{\left(R_i\right)}^{-1}\·y_i;$

Wherein,

Be i the data carrier symbol after the merging, R _iBe the NI Matrix Estimation value of i data carrier, y _iThe column vector that constitutes for the response of i data carrier on each reception antenna, Column vector for each reception antenna channel response estimated value formation.

5. like claim 1,2 or 3 described methods, it is characterized in that, said data to be tested carrier wave carried out non-interference suppress to merge detection, specifically comprise:

Calculate merging back symbol according to following formula:

6. a self-adaptive multi antenna diversity merges interference blanking unit, it is characterized in that said device comprises:

The antenna noise measurement module is used to measure the noise power on the every reception antenna;

The self-adaptive decision module, whether the ratio of average of diagonal entry sum and the noise power on each reception antenna of NI matrix of data to be tested carrier wave that is used to judge estimation is greater than predetermined threshold value;

Merge processing module, be used for court verdict, if court verdict is for being then said data to be tested carrier wave to be disturbed and suppress to merge detection according to said self-adaptive decision module; Otherwise, said data to be tested carrier wave is carried out non-interference suppresses to merge detection.

7. device as claimed in claim 6 is characterized in that, said device also comprises:

Channel estimation module is used for drawing through channel estimating the channel response estimated value of each data carrier on the Resource Block;

The NI matrix estimation module, the said channel response estimated value that is used for drawing according to said channel estimation module is estimated the estimated value of the NI matrix of each data carrier.

8. device as claimed in claim 6 is characterized in that,

Said antenna noise measurement module is used for, and measures the noise power on said each reception antenna through the mode of unloaded ripple or quiet frame.

9. like claim 6,7 or 8 described devices, it is characterized in that,

Said merging processing module is used for, and when disturbing inhibition to merge detection to said data to be tested carrier wave, specifically comprises:

Calculate the NI inverse of a matrix matrix of said data to be tested carrier wave, and calculate merging back symbol according to following formula:

${\hat{S}}_i=H_i^H\·{\left(R_i\right)}^{-1}\·y_i;$

Wherein,

Be i the data carrier symbol after the merging, R _iBe the NI Matrix Estimation value of i data carrier, y _iThe column vector that constitutes for the response of i data carrier on each reception antenna,

Column vector for each reception antenna channel response estimated value formation.

10. like claim 6,7 or 8 described devices, it is characterized in that,

Said merging processing module is used for, and said data to be tested carrier wave is carried out non-interference suppress to merge when detecting, and specifically comprises:

Calculate merging back symbol according to following formula:

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