CN102932039A - Antenna calibration method and system - Google Patents

Abstract

The invention provides an antenna calibration method and system, which aim at solving the problem that calibration factors obtained by the conventional calibration method are inaccurate and cannot be used for accurately calibrating antennas. The method comprises the following steps of: performing N times of channel estimation on each antenna in an antenna array within one antenna calibration period, thus obtaining vectors Rk reflecting the amplitudes and phase characteristics of the antennas and obtained by the channel estimation procedures; aimed at an antenna k, sequentially judging whether vector pairs formed by vectors RKi obtained from the i times of channel estimation and vectors RKj obtained from the j times of channel estimation meet preset conditions; counting the number of the vector pairs meeting the preset conditions; determining the effective vector of the antenna k according to the number of the vector pairs meeting the preset conditions; and calculating the calibration factor of the antenna k according to the effective vector, and calibrating the antenna k according to the calibration factor. The method disclosed by the invention can guarantee that the calculated calibration factors are more accurate, and improve the accuracy and reliability of antenna calibration.

Description

A kind of antenna calibration method and system

Technical field

The present invention relates to communication technical field, particularly relate to a kind of antenna calibration method and system.

Background technology

Smart antenna is time-division (Tim _eDi _vi _si _oN, TD) one of key technology of system, depend on smart antenna and realize that wave beam forming can effectively reduce the interference between the user, the main process of wave beam forming is: uplink receiving is judged the terminal arrival bearing by the phase relation of each antenna, descendingly carries out figuration according to arrival bearing again.

Because extraneous factors such as self hardware reason and temperature, phase place and amplitude between each passage of antenna system are devious.Therefore, in order effectively to realize the function of smart antenna, periodically aerial array is carried out antenna calibration with regard to needs, compensate phase place and amplitude error between each service aisle.

Present antenna calibration method mainly comprises following two kinds:

(1) carry out one time channel estimating in a calibration cycle, phase place, the amplitude error of the passage that is obtained by channel estimating calculate calibration factor, then utilize calibration factor that antenna is calibrated.

But this method is only carried out channel estimating one time, and its channel phases that obtains, amplitude error are easy to be subjected to the impact of extraneous factor, thereby causes the calibration factor that calculates inaccurate, exactly boresight antenna.

(2) in a calibration cycle, carry out repeatedly channel estimating, with the mean value of channel estimation results repeatedly phase place, the amplitude error as passage, phase place, the amplitude error of recycling passage calculate calibration factor, then utilize calibration factor that antenna is calibrated.

This method is passed through repeatedly channel estimating, for channel status and the stable aerial array of extraneous factor, can access accurately calibration factor with respect to above-mentioned antenna calibration method that carries out a channel estimating, the operation of aerial array, operating position from existing network, this method are effective for most of aerial array.

But, if the aerial array channel status is unstable or have interference, phase place, amplitude error have significantly and change, the mean value that directly calculate repeatedly channel estimation results this moment not only can not obtain accurately phase place, amplitude error, on the contrary so that unpredictable results appears in phase place, amplitude error, the calibration factor that calculates like this is complete mistake, unpredictable, even can directly antenna be judged as unavailablely in the antenna calibration process, affects the normal use of antenna.

Summary of the invention

Technical problem to be solved by this invention provides a kind of antenna calibration method and system, and is inaccurate to solve the calibration factor that obtains in the existing calibration steps, accurately the problem of boresight antenna.

In order to address the above problem, the invention discloses a kind of antenna calibration method, comprising:

For each antenna in the aerial array, carry out the N secondary channel in the cycle at an antenna calibration and estimate, obtain each secondary channel and estimate the reflection antenna amplitude that obtains and the vector R of phase characteristic _k, wherein, N is positive integer, k=1, and 2 ..., ANT, ANT are total number of antenna;

For antenna k, judge successively the vector R that the estimation of i secondary channel obtains _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jWhether the vector that forms is pre-conditioned to satisfying, i=1, and 2 ..., N, j=1,2 ..., N;

Statistics satisfies the described pre-conditioned right number of vector;

According to satisfying effective vector that the described pre-conditioned right number of vector is determined described antenna k;

Calculate the calibration factor of antenna k according to described effective vector, and according to described calibration factor antenna k is calibrated.

Preferably, the described vector R that judges that successively the estimation of i secondary channel obtains _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jThe vector that forms comprises whether satisfying pre-conditioned step:

Compute vectors R _k ⁱWith vector R _k ^jDifference R _k ⁱ-R _k ^j

Judge described R _k ⁱ-R _k ^jAmplitude || R _k ⁱ-R _k ^j|| whether be less than or equal to R _k ⁱAmplitude || R _k ⁱ|| with default threshold T _ThresholdProduct;

If then determine vector R _k ⁱWith vector R _k ^jThe vector that forms is described pre-conditioned to satisfying, described vector R _k ⁱWith vector R _k ^jUnanimously.

Preferably, described foundation satisfies the described pre-conditioned right number of vector and determines that the step of effective vector of described antenna k comprises:

Estimate the vector R that obtains for the i secondary channel of antenna k _k ⁱ, obtain successively vector R _k ^jIn with vector R _k ⁱConsistent vector, more described and vector R _k ⁱThe number of consistent vector and the size of N/2;

As described and vector R _k ⁱThe number of consistent vector is determined described vector R during more than or equal to N/2 _k ⁱBe effective vector;

As described and vector R _k ⁱThe individual number average of consistent vector determines that described antenna k does not have effective vector during less than N/2.

Preferably, when there was effective vector in antenna k, described antenna k was effective antenna; When there was not effective vector in antenna k, described antenna k was invalid antenna;

When having invalid antenna in the aerial array, described method also comprises:

Obtain the vector R of described reference antenna m take any one effective antenna m wherein as reference antenna _mAmplitude and phase place, m=1,2 ..., ANT;

According to described vector R _mAmplitude and the phase place vector R that obtains successively antenna n in the aerial array _nCorresponding new vector R _n', n=1,2 ..., ANT;

For antenna n, according to described new vector R _n' judge whether antenna n exists effective vector;

If then calculate calibration factor, and according to described calibration factor antenna n calibrated;

If not, then obtain in the antenna calibration cycle and antenna n is calibrated the calibration result that obtains according to the calibration factor of antenna n, with the calibration result of described calibration result as this antenna calibration cycle internal antenna n.

Preferably, the described vector R of described foundation _mAmplitude and the phase place vector R that obtains successively antenna n in the aerial array _nCorresponding new vector R _n' step comprise:

Keep vector R _nAmplitude constant, with vector R _nDescribed vector R turns clockwise _mPhase place, obtain corresponding new vector R _n'.

On the other hand, the invention also discloses a kind of antenna calibration system, comprising:

The vector acquisition module is used for each antenna for aerial array, carries out the N secondary channel in the cycle at an antenna calibration and estimates, obtains reflection antenna amplitude that each secondary channel estimation obtains and the vector R of phase characteristic _k, wherein, N is positive integer, k=1, and 2 ..., ANT, ANT are total number of antenna;

The first vector is used for for antenna k judge module, judges successively the vector R that the estimation of i secondary channel obtains _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jWhether the vector that forms is pre-conditioned to satisfying, i=1, and 2 ..., N, j=1,2 ..., N;

Statistical module is used for statistics and satisfies the described pre-conditioned right number of vector;

Effectively the vector determination module is used for according to satisfying effective vector that the described pre-conditioned right number of vector is determined described antenna k;

The first calibration module is used for the calibration factor according to described effective vector calculating antenna k, and according to described calibration factor antenna k is calibrated.

Preferably, described the first vector comprises judge module:

Difference computational unit is used for compute vectors R _k ⁱWith vector R _k ^jDifference R _k ⁱ-R _k ^j

Judging unit is used for judging described R _k ⁱ-R _k ^jAmplitude || R _k ⁱ-R _k ^j|| whether be less than or equal to R _k ⁱAmplitude || R _k ⁱ|| with default threshold T _ThresholdProduct;

Determining unit, be used for when the judged result of judging unit when being, determine vector R _k ⁱWith vector R _k ^jThe vector that forms is described pre-conditioned to satisfying, described vector R _k ⁱWith vector R _k ^jUnanimously.

Preferably, described effective vector determination module comprises:

Comparing unit is for the vector R that estimates for the i secondary channel of antenna k to obtain _k ⁱ, obtain successively vector R _k ^jIn with vector R _k ⁱConsistent vector, more described and vector R _k ⁱThe number of consistent vector and the size of N/2;

First effective vector determining unit, the comparative result that is used for when comparing unit is described and vector R _k ⁱThe number of consistent vector is determined described vector R during more than or equal to N/2 _k ⁱBe effective vector;

Second effective vector determining unit, the comparative result that is used for when comparing unit is described and vector R _k ⁱThe individual number average of consistent vector determines that described antenna k does not have effective vector during less than N/2.

Preferably, when there was effective vector in antenna k, described antenna k was effective antenna; When there was not effective vector in antenna k, described antenna k was invalid antenna;

Described system also comprises:

Reference antenna vector acquisition module is used for when there is invalid antenna in aerial array, obtains the vector R of described reference antenna m take any one effective antenna m wherein as reference antenna _mAmplitude and phase place, _m=1,2 ..., ANT;

New vector acquisition module is used for according to described vector R _mAmplitude and the phase place vector R that obtains successively antenna n in the aerial array _nCorresponding new vector R _n', n=1,2 ..., ANT;

The second vector is used for for antenna n judge module, according to described new vector R _n' judge whether antenna n exists effective vector;

The second calibration module, be used for when the second vector to the judged result of judge module when being, calculating calibration factor, and the described calibration factor of foundation is calibrated antenna n;

The calibration result determination module, be used for when the second vector when the determination result is NO to judge module, obtain in the antenna calibration cycle and antenna n is calibrated the calibration result that obtains according to the calibration factor of antenna n, with the calibration result of described calibration result as this antenna calibration cycle internal antenna n.

Preferably, described new vector acquisition module comprises:

Rotary unit is used for keeping vector R _nAmplitude constant, with vector R _nDescribed vector R turns clockwise _mPhase place, obtain corresponding new vector R _n'.

Compared with prior art, the present invention includes following advantage:

At first, the present invention is for each antenna in the aerial array, carries out the N secondary channel in the cycle at an antenna calibration and estimates, obtains each secondary channel and estimates the reflection antenna amplitude that obtains and the vector R of phase characteristic _k, then for antenna k, judge successively the vector R that the estimation of i secondary channel obtains _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jWhether the vector that forms is pre-conditioned to satisfying, and statistics satisfies the described pre-conditioned right number of vector, last according to satisfying effective vector that the described pre-conditioned right number of vector is determined described antenna k, calculate again the calibration factor of antenna k according to described effective vector, and according to described calibration factor antenna k is calibrated.Screen by the result to the repeatedly channel estimating of antenna k, determine effective vector wherein, and then carry out the calculating of calibration factor according to described effective vector, so that the calibration factor that calculates is more accurate, thereby improve accuracy and the reliability of antenna calibration.

Secondly, the present invention is by utilizing phasor difference R _k ⁱ-R _k ^jCalculate, whether amplitude and the phase place that can judge simultaneously this phasor difference satisfy condition, and do not need amplitude and phase place are separately judged, and then carry out logical operation, therefore, operand of the present invention is little, can simplify computational process, improve the efficient of antenna calibration.

Description of drawings

Fig. 1 is the flow chart of the embodiment of the invention one described a kind of antenna calibration method;

Fig. 2 is the flow chart of the embodiment of the invention two described a kind of antenna calibration methods;

Fig. 3 is the schematic diagram of the phasor difference of the described vector R1 of the embodiment of the invention and vector R2;

Fig. 4 is that the described phasor difference R1-R2 of the embodiment of the invention drops on the schematic diagram in the circle;

Fig. 5 is that the described phasor difference R1-R2 of the embodiment of the invention drops on the outer schematic diagram of circle;

Fig. 6 is the structured flowchart of the embodiment of the invention three described a kind of antenna calibration systems;

Fig. 7 is that the embodiment of the invention three described the first vectors are to the structured flowchart of judge module.

Embodiment

For above-mentioned purpose of the present invention, feature and advantage can be become apparent more, the present invention is further detailed explanation below in conjunction with the drawings and specific embodiments.

The present invention is by carrying out repeatedly channel estimating in a calibration cycle, then from the result of channel estimating repeatedly, filter out effective vector, calculate calibration factor according to effective vector again, thereby so that the calibration factor that calculates is more accurate, improve accuracy and the reliability of antenna calibration.

With reference to Fig. 1, show the flow chart of the embodiment of the invention one described a kind of antenna calibration method, in the antenna calibration process, the most important thing is to calculate the process of calibration factor, the accuracy of calibration factor has determined the accuracy of antenna calibration.

In the prior art, the inaccurate problem of calibration factor that calculates when only carrying out a channel estimating adopts repeatedly channel estimating usually, then gets repeatedly the method for the mean value of channel estimation results and calculates calibration factor.But the situation that the method for this repeatedly channel estimating is unstable for the aerial array channel status or existence is disturbed not only can not calculate accurately calibration factor, and it is full of prunes, unpredictable also might making the calibration factor that obtains.

Therefore, the present invention is directed to the defective of above-mentioned repeatedly channel estimation methods, proposed channel estimation results is repeatedly screened, select effective vector wherein, and then according to described effective vector calculating calibration factor, thereby so that the calibration factor that calculates is more accurate.

As shown in Figure 1, described method comprises:

Step S101 for each antenna in the aerial array, carries out the N secondary channel at an antenna calibration and estimates in the cycle, obtain each secondary channel and estimate the reflection antenna amplitude that obtains and the vector R of phase characteristic _k

Wherein, N is positive integer, k=1, and 2 ..., ANT, ANT are total number of antenna.

At first, for each antenna in the aerial array, carry out repeatedly channel estimating in the cycle at an antenna calibration, and then calculate calibration factor according to the result of channel estimating repeatedly.

After each channel estimating, can both obtain the vector of a reflection antenna amplitude and phase characteristic, the vector that the embodiment of the invention utilizes channel estimating to obtain carries out the calculating of calibration factor, for concrete computational process, will introduce in detail in the following embodiments.

Step S102 for antenna k, judges the vector R that the estimation of i secondary channel obtains successively _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jWhether the vector that forms is pre-conditioned to satisfying.

Wherein, i=1,2 ..., N, j=1,2 ..., N.

Step S103, statistics satisfies the described pre-conditioned right number of vector.

Step S104 is according to satisfying effective vector that the described pre-conditioned right number of vector is determined described antenna k.

Above-mentioned steps S102-step S104 is exactly the process of the effective vector of screening from the result of channel estimating repeatedly, for concrete screening process, will introduce in detail in the following embodiments, and the present embodiment is introduced no longer in detail at this.

Step S105, according to the calibration factor of described effective vector calculating antenna k, and the described calibration factor of foundation is calibrated antenna k.

After filtering out effective vector, namely can calculate according to this effective vector meter the calibration factor of antenna, then according to calibration factor antenna is calibrated.

The embodiment of the invention is for each antenna in the aerial array, carries out the N secondary channel in the cycle at an antenna calibration and estimates, obtains each secondary channel and estimates the reflection antenna amplitude that obtains and the vector R of phase characteristic _k, then for antenna k, judge successively the vector R that the estimation of i secondary channel obtains _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jWhether the vector that forms is pre-conditioned to satisfying, and statistics satisfies the described pre-conditioned right number of vector, last according to satisfying effective vector that the described pre-conditioned right number of vector is determined described antenna k, calculate again the calibration factor of antenna k according to described effective vector, and according to described calibration factor antenna k is calibrated.Screen by the result to the repeatedly channel estimating of antenna k, determine effective vector wherein, and then carry out the calculating of calibration factor according to described effective vector, so that the calibration factor that calculates is more accurate, thereby improve accuracy and the reliability of antenna calibration.

Below, the antenna calibration method that the present invention is proposed describes in detail.

With reference to Fig. 2, show the flow chart of the embodiment of the invention two described a kind of antenna calibration methods, described method comprises:

Step S201 for each antenna in the aerial array, carries out the N secondary channel at an antenna calibration and estimates in the cycle, obtain each secondary channel and estimate the reflection antenna amplitude that obtains and the vector R of phase characteristic _k

Wherein, N is positive integer, k=1, and 2 ..., ANT, ANT are total number of antenna.

For an antenna, after each channel estimating, can both obtain a vector, this vector reflects the amplitude of this antenna and the deviate of phase place, then calculate the amplitude of this antenna of compensation and the calibration factor of phase deviation by these deviates, according to this calibration factor antenna is calibrated.

The embodiment of the invention is exactly to filter out the channel estimation results that satisfies condition from the vector that these channel estimating obtain, and recycles these channel estimation results that satisfy condition and calculates calibration factor, thereby make the calibration factor that obtains more accurate.

For the screening process of amplitude and phase place, can compare each channel estimation results, then from wherein selecting the more stable result of amplitude and phase place.

A kind of screening technique is respectively amplitude and phase place to be judged, and then carries out analysis-by-synthesis, but the operand of the method is large, logic is complicated.

Preferably, the embodiment of the invention is introduced definition of vector, for antenna k, utilizes it is carried out the vector R that reflects antenna amplitude and phase characteristic that channel estimating obtains _kCarry out Screening Treatment.

Step S202 for antenna k, judges the vector R that the estimation of i secondary channel obtains successively _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jWhether the vector that forms is pre-conditioned to satisfying.

Wherein, i=1,2 ..., N, j=1,2 ..., N.

For at an antenna calibration in the cycle, repeatedly the amplitude and the phase place that obtain of channel estimating should present stable state, therefore, whether the result that the embodiment of the invention is judged this twice channel estimating by the difference of judging twice amplitude between the channel estimation results and phase place consistent (difference illustrates then that within the specific limits the result of twice channel estimating is consistent, consistent also namely satisfy default adjusting condition).

In the present embodiment because amplitude and phase place that each channel estimating obtains are all used vector representation, therefore by calculate phasor difference that twice channel estimating obtain vector can reflect twice between the channel estimation results amplitude and the deviation of phase place.

At first, phasor difference being analyzed, take vector R1 and vector R2 as example, as shown in Figure 3, is the schematic diagram of the phasor difference of vector R1 and vector R2, and among the figure, vector R1-R2 is vector R1 and the described phasor difference of vector R2, and its direction is pointed to R1 by R2.

If within the specific limits whether the difference of judging the amplitude of vector R1 and vector R2 and phase place, can set take the end of R1 and draw a circle as the center of circle, if phasor difference R1-R2 drop on the circle in illustrate that the amplitude of two vectors is close with phase place, difference within the specific limits, otherwise the explanation amplitude is with phasic difference is larger mutually.And, can set this radius of a circle and be || R1|| * T _Threshold, T wherein _ThresholdBe default threshold value, for its concrete numerical value, the embodiment of the invention is not limited.

Can learn by analysis, when R1 and R2 were on the same straight line, its amplitude difference was maximum, and the maximum of amplitude difference is that radius of a circle is || R1|| * T _ThresholdWhen phasor difference R1-R2 was vertical with R1, the phase difference of R1 and R2 was maximum, and the maximum of phase difference is arctg (T _Threshold).

Therefore, guarantee that phasor difference R1-R2 drops in the circle, then require the amplitude of this phasor difference can not be greater than || R1|| * T _Threshold, and the phase place of this phasor difference can not be greater than arcrg (T _Threshold),

Be that phasor difference R1-R2 satisfies following two formula:

|| R1-R2||≤|| R1||*T _ThresholdFormula 1

Arg (R1-R2)≤arctg (T _Threshold) formula 2

Will || R1|| * T _ThresholdBe converted to the db value and be 20*log (1-T _Threshold), for example, T _Threshold=1/16 o'clock is 0.56db through the maximum of calculating amplitude difference, and the maximum of phase difference is 3.58 °, and for concrete computational process, the present embodiment is introduced no longer in detail.

Although in order to guarantee that phasor difference R1-R2 drops in the circle, phasor difference R1-R2 need to satisfy above-mentioned formula 1 and formula 2,, when practical application, only need to judge whether phasor difference R1-R2 satisfies formula 1 and get final product, because if phasor difference R1-R2 has satisfied formula 1, it also necessarily satisfies formula 2 so.Therefore, only need once judge according to the definition of phasor difference and can judge simultaneously amplitude and phase place, thus can the simplified operation process.

As shown in Figure 4 and Figure 5, be respectively phasor difference R1-R2 in circle and the schematic diagram of phasor difference R1-R2 outside justifying.Phasor difference R1-R2 among Fig. 4 namely satisfies above-mentioned formula 1 and formula 2, and the phasor difference R1-R2 among Fig. 5 does not satisfy above-mentioned formula 1 and formula 2.

Therefore, in this step, the vector R that obtains for channel estimating repeatedly _k, judge successively the vector R that the estimation of i secondary channel obtains _k ⁱWhether the vector that the vector of estimating to obtain with the j secondary channel forms is pre-conditioned to satisfying, and namely judges phasor difference R _k ⁱ-R _k ^jAmplitude and phase place whether within the specific limits.If in this scope, the result that twice channel estimating then is described is consistent, i.e. R _k ⁱAnd R _k ^jThe vector that forms is pre-conditioned to satisfying.

Still setting threshold value is T _Threshold, suppose each antenna repeatedly the vector that obtains of channel estimating be respectively: R ₁ ¹, R ₁ ²..., R ₁ ^N..., R _ANT ¹, R _ANT ²..., R _ANT ^N, be introduced as an example of antenna k example in the present embodiment.

This step S202 specifically can comprise:

Substep a1, compute vectors R _k ⁱWith vector R _k ^jDifference R _k ⁱ-R _k ^j

Substep a2 judges described R _k ⁱ-R _k ^jAmplitude || R _k ⁱ-R _k ^j|| whether be less than or equal to R _k ⁱAmplitude || R _k ⁱ|| with default threshold T _ThresholdProduct;

Substep a3 if the judged result of substep a2 is yes, then determines vector R _k ⁱWith vector R _k ^jThe vector that forms is described pre-conditioned to satisfying.

That is to say, if R _k ⁱ-R _k ^jSatisfy following formula 3 (according to the description among the step S202, if satisfied formula 3, also just can satisfy formula 4, therefore not need again judgment formula 4), vector R then is described _k ⁱWith vector R _k ^jThe vector that forms is described pre-conditioned to satisfying, and namely the i secondary channel is estimated consistent (the vector R of result with the estimation of j secondary channel _k ⁱWith vector R _k ^jUnanimously).

$\left|\right|R_k^i-R_k^j\left|\right|\≤\left|\right|R_k^i\left|\right|*T_{\mathrm{threshold}}$ Formula 3

$\arg (R_k^i-R_k^j)\≤\mathrm{arctg}\left(T_{\mathrm{threshold}}\right)$ Formula 4

After each secondary channel estimated result is judged in twos, can be recorded in judged result in the following table one:

Table one

Wherein, whether " consistent " namely represents vector R _k ⁱWith vector R _k ^jThe vector that forms is described pre-conditioned to satisfying.

The present embodiment is by utilizing phasor difference R _k ⁱ-R _k ^jCalculate, whether amplitude and the phase place that can judge simultaneously this phasor difference satisfy condition, and do not need amplitude and phase place are separately judged, and then carry out logical operation, therefore, operand of the present invention is little, can simplify computational process, improve the efficient of antenna calibration.

Step S203, statistics satisfies the described pre-conditioned right number of vector.

After in step S202 each secondary channel estimated result being judged in twos, add up and satisfy the right number of pre-conditioned vector, i.e. then the consistent number of times of result determines effective vector of antenna k according to the consistent number of times of result.

Step S204 is according to satisfying effective vector that the described pre-conditioned right number of vector is determined described antenna k.

Because at an antenna calibration in the cycle, repeatedly the amplitude and the phase place that obtain of channel estimating should present stable state, the embodiment of the invention judges by the difference of judging twice amplitude between the channel estimation results and phase place whether the result of this twice channel estimating is consistent, if the consistent number of times of result thinks then that more than or equal to inconsistent number of times (being that the consistent number of times of result is more than or equal to N/2) result of channel estimating is effective result.

Therefore, this step S204 specifically can comprise:

Substep b1 estimates the vector R that obtains for the i secondary channel of antenna k _k ⁱ, obtain successively vector R _k ^jIn with vector R _k ⁱConsistent vector, more described and vector R _k ⁱThe number of consistent vector and the size of N/2;

Substep b2 is as described and vector R _k ⁱThe number of consistent vector is determined described vector R during more than or equal to N/2 _k ⁱBe effective vector;

Substep b3 is as described and vector R _k ⁱThe individual number average of consistent vector determines that described antenna k does not have effective vector during less than N/2.

For example, when N=5, obtain following table two after the result that this 5 secondary channel is estimated judges, from table two, can find out, for the vector R that the first time, channel estimating obtained _k ¹, the vector R that this 5 secondary channel estimated result obtains _k ¹, R _k ², R _k ³, R _k ⁴And R _k ⁵In with R _k ¹Consistent vector has 3, is respectively R _k ¹, R _k2 and R _k ³, so and R _k ¹The number of consistent vector is greater than N/2, then vector R _k ¹Be effective vector.For vector R _k ², R _k ³, R _k ⁴And R _k ⁵Deterministic process and above-mentioned vector R _k ¹Similar, the present embodiment is discussed no longer in detail at this, judges at last R _k ¹, R _k ²And R _k ³Be effective vector, R _k ⁴And R _k ⁵Be invalid vector.

Table two

But, need to prove, in the normal situation of antenna, can only judge wherein that one group of vector is effective vector, be effective vector if judge at least two group vectors, illustrate that then this antenna k breaks down, and need to keep in repair.

For example, when N=6, after judging, the result that this 6 secondary channel is estimated obtains following table three, as can be seen from Table III, and R _k ¹, R _k ², R _k ³, R _k ⁴, R _k ⁵And R _k ⁶Be effective vector, but R wherein _k ¹, R _k ²And R _k ³Unanimously, be one group of effective vector, R _k ⁴, R _k ⁵And R _k ⁶Unanimously, be one group of effective vector, namely comprise in this case two groups of effective vectors, illustrate that fault has appearred in this antenna k.

R k 1

R k 2

R k 3

R k 4

R k 5

R k 6

R k 1

Unanimously

Unanimously

Unanimously

Inconsistent

Inconsistent

Inconsistent

R k 2

Unanimously

Unanimously

Unanimously

Inconsistent

Inconsistent

Inconsistent

R k 3

Unanimously

Unanimously

Unanimously

Inconsistent

Inconsistent

Inconsistent

R k 4

Inconsistent

Inconsistent

Inconsistent

Unanimously

Unanimously

Unanimously

R k 5

Inconsistent

Inconsistent

Inconsistent

Unanimously

Unanimously

Unanimously

R k 6

Inconsistent

Inconsistent

Inconsistent

Unanimously

Unanimously

Unanimously

Table three

Step S205, according to the calibration factor of described effective vector calculating antenna k, and the described calibration factor of foundation is calibrated antenna k.After determining effective vector of antenna k, can calculate according to effective vector the calibration factor of antenna k, then according to described calibration factor antenna k is calibrated.Concrete, at first all vectors in the effective vector that obtains among the step S204 are averaged, obtain mean vector

Then according to described mean vector

Calculate the calibration factor factor (k) of antenna k by following formula:

$\mathrm{factor}\left(k\right)=\frac{\sqrt{\mathrm{Min}\left(\right|\left|R_i\right|\left|\right)}}{\left|\right|{\stackrel{\‾}{R}}_k\left|\right|}*{\stackrel{\‾}{R}}_k^{*},$ i＝1，2，…，ANT

In addition, when there was effective vector in antenna k, described antenna k was effective antenna; When there was not effective vector in antenna k, described antenna k was invalid antenna.

In this calibration cycle, through after once calculating, invalid antenna may appear to all antennas, if there is invalid antenna, also to further adjusts the antenna in the aerial array, and then judge calculating.

Characteristic according to antenna can learn, even the absolute phase of each antenna, amplitude are because saltus step appears in self or outside cause, relative phase, amplitude between each antenna substantially still remain unchanged.And the realization of smart antenna function also just depends on the relative phase relation between antenna, if therefore said method is judged and had invalid antenna, then can adjust each antenna according to the relative phase between antenna.

Concrete, can be take any one effective antenna m wherein as reference antenna, with all the turn clockwise vector R of this effective antenna m of each antenna (comprising antenna m) _mPhase angle, and the maintenance amplitude is constant, thereby obtains each antenna with respect to the relative phase relation of effective antenna m, and then postrotational antenna is judged.

Therefore, when having invalid antenna in the aerial array, described method also comprises:

Step S206 obtains the vector R of described reference antenna m take any one effective antenna m wherein as reference antenna _mAmplitude and phase place, m=1,2 ..., ANT.

Step S207 is according to described vector R _mAmplitude and the phase place vector R that obtains successively antenna n in the aerial array _nCorresponding new vector R _n', n=1,2 ..., ANT.

This step S207 specifically can comprise:

Keep vector R _nAmplitude constant, with vector R _nDescribed vector R turns clockwise _mPhase place, obtain corresponding new vector R _n'.

Above-mentioned R _n' can calculate with following formula:

${R_n}^{\′}=R_m^{*}*R_n/\left|\right|R_m\left|\right|$

Step S208 is for antenna n, according to described new vector R _n' judge whether antenna n exists effective vector.

For antenna n, after the adjustment through above-mentioned steps S207, obtained corresponding new vector R _n', then to the R after adjusting _n' carry out above-mentioned steps S202-step S205, for new vector R _n' judge whether antenna n exists effective vector.

Step S209 is if then calculate calibration factor, and according to described calibration factor antenna n is calibrated.

There is effective vector if judge antenna n among the step S208, illustrates that then the antenna n after this adjustment is effective antenna, at this moment, calculate calibration factor according to effective vector of determining, and according to described calibration factor antenna n is calibrated.

Get final product with reference to above-mentioned steps S202-step S205 for concrete process, the present embodiment is discussed no longer in detail at this.

Step S210 if not, then obtains in the antenna calibration cycle and antenna n is calibrated the calibration result that obtains according to the calibration factor of antenna n, with the calibration result of described calibration result as this antenna calibration cycle internal antenna n.

At first, need to prove, at each antenna calibration in the cycle, be for the calibration result of wherein arbitrary antenna: adopt above-mentioned steps S201-step S205 to calculate after the calibration factor of this antenna, the result who arrives after according to described calibration factor this antenna being calibrated.

Do not have effective vector if judge antenna n among the step S208, illustrate that then the antenna n after this adjustment still is invalid antenna, still can not calculate calibration factor for this antenna n this moment.Therefore, for this situation, the present invention will obtain the calibration result of an antenna calibration cycle internal antenna n, and with the calibration result of the described upper antenna calibration cycle internal antenna n calibration result as this antenna calibration cycle internal antenna n.

Concrete, can judge whether described antenna n is effective antenna in the upper antenna calibration cycle, if effective antenna, then with the calibration result of the described upper antenna calibration cycle internal antenna n calibration result as this antenna calibration cycle internal antenna n, if also be invalid antenna at a upper antenna calibration cycle internal antenna n, illustrate that then fault may appear in antenna n, no longer carry out calibration process to antenna n this moment.

For example, the current antenna calibration cycle is the cycle 5, is invalid antenna if judge antenna n within this cycle 5, and still is invalid antenna after once adjusting, and whether then search antenna n within the cycle 4 is effective antenna.If internal antenna n is effective antenna in the cycles 4, then with the calibration result of the cycle 4 internal antenna n calibration result as this cycle 5 internal antenna n; If internal antenna n is invalid antenna in the cycles 4, illustrate that then fault may appear in antenna n.

The embodiment of the invention is with respect to the improvements of above-described embodiment one, increased the processing procedure for abnormal conditions, for the situation that has invalid antenna in the aerial array, to further the antenna in these antenna array be adjusted processing, to realize the calibration process to these antenna, further guaranteed accuracy and the integrality of antenna calibration.

With reference to Fig. 6, show the structured flowchart of the embodiment of the invention three described a kind of antenna calibration systems, described system comprises: vector acquisition module 601, the first vector are to judge module 602, statistical module 603, effectively vector determination module 604, the first calibration module 605, reference antenna vector acquisition module 606, new vector acquisition module 607, the second vector be to judge module 608, the second calibration module 609 and calibration result determination module 610.

Wherein,

Vector acquisition module 601 is used for each antenna for aerial array, carries out the N secondary channel in the cycle at an antenna calibration and estimates, obtains reflection antenna amplitude that each secondary channel estimation obtains and the vector R of phase characteristic _k, wherein, N is positive integer, k=1, and 2 ..., ANT, ANT are total number of antenna;

The first vector is used for for antenna k judge module 602, judges successively the vector R that the estimation of i secondary channel obtains _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jWhether the vector that forms is pre-conditioned to satisfying, i=1, and 2 ..., N, j=1,2 ..., N;

As shown in Figure 7, described the first vector comprises judge module 602:

Difference computational unit 701 is used for compute vectors R _k ⁱWith vector R _k ^jDifference R _k ⁱ-R _k ^j

Judging unit 702 is used for judging described R _k ⁱ-R _k ^jAmplitude || R _k ⁱ-R _k ^j|| whether be less than or equal to R _k ⁱAmplitude || R _k ⁱ|| with default threshold T _ThresholdProduct;

Determining unit 703, be used for when the judged result of judging unit when being, determine vector R _k ⁱWith vector R _k ^jThe vector that forms is described pre-conditioned to satisfying, described vector R _k ⁱWith vector R _k ^jUnanimously.

Statistical module 603 is used for statistics and satisfies the described pre-conditioned right number of vector;

Effectively vector determination module 604 is used for according to satisfying effective vector that the described pre-conditioned right number of vector is determined described antenna k;

Described effective vector determination module 604 comprises:

Comparing unit is for the vector R that estimates for the i secondary channel of antenna k to obtain _k ⁱ, obtain successively vector R _k ^jIn with vector R _k ⁱConsistent vector, more described and vector R _k ⁱThe number of consistent vector and the size of N/2;

First effective vector determining unit, the comparative result that is used for when comparing unit is described and vector R _k ⁱThe number of consistent vector is determined described vector R during more than or equal to N/2 _k ⁱBe effective vector;

Second effective vector determining unit, the comparative result that is used for when comparing unit is described and vector R _k ⁱThe individual number average of consistent vector determines that described antenna k does not have effective vector during less than N/2.

The first calibration module 605 is used for the calibration factor according to described effective vector calculating antenna k, and according to described calibration factor antenna k is calibrated.

In addition, when there was effective vector in antenna k, described antenna k was effective antenna; When there was not effective vector in antenna k, described antenna k was invalid antenna.

Described system also comprises:

Reference antenna vector acquisition module 606 is used for when there is invalid antenna in aerial array, obtains the vector R of described reference antenna m take any one effective antenna m wherein as reference antenna _mAmplitude and phase place, m=1,2 ..., ANT;

New vector acquisition module 607 is used for according to described vector R _mAmplitude and the phase place vector R that obtains successively antenna n in the aerial array _nCorresponding new vector R _n', n=1,2 ..., ANT;

Described new vector acquisition module 607 comprises:

Rotary unit is used for keeping vector R _nAmplitude constant, with vector R _nDescribed vector R turns clockwise _mPhase place, obtain corresponding new vector R _n'.

The second vector is used for for antenna n judge module 608, according to described new vector R _n' judge whether antenna n exists effective vector;

The second calibration module 609, be used for when the second vector to the judged result of judge module when being, calculating calibration factor, and the described calibration factor of foundation is calibrated antenna n;

Calibration result determination module 610 is used for obtaining the calibration result of an antenna calibration cycle internal antenna n, with the calibration result of described calibration result as this antenna calibration cycle internal antenna n when the second vector when the determination result is NO to judge module.

The embodiment of the invention is for each antenna in the aerial array, carries out the N secondary channel in the cycle at an antenna calibration and estimates, obtains each secondary channel and estimates the reflection antenna amplitude that obtains and the vector R of phase characteristic _k, then for antenna k, judge successively the vector R that the estimation of i secondary channel obtains _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jWhether the vector that forms is pre-conditioned to satisfying, and statistics satisfies the described pre-conditioned right number of vector, last according to satisfying effective vector that the described pre-conditioned right number of vector is determined described antenna k, calculate again the calibration factor of antenna k according to described effective vector, and according to described calibration factor antenna k is calibrated.Screen by the result to the repeatedly channel estimating of antenna k, determine effective vector wherein, and then carry out the calculating of calibration factor according to described effective vector, so that the calibration factor that calculates is more accurate, thereby improve accuracy and the reliability of antenna calibration.

Secondly, the embodiment of the invention is by utilizing phasor difference R _k ⁱ-R _k ^jCalculate, whether amplitude and the phase place that can judge simultaneously this phasor difference satisfy condition, and do not need amplitude and phase place are separately judged, and then carry out logical operation, therefore, operand of the present invention is little, can simplify computational process, improve the efficient of antenna calibration.

For system embodiment because itself and embodiment of the method basic simlarity, so describe fairly simple, relevant part gets final product referring to the part explanation of embodiment of the method.

Each embodiment in this specification all adopts the mode of going forward one by one to describe, and what each embodiment stressed is and the difference of other embodiment that identical similar part is mutually referring to getting final product between each embodiment.

The present invention can describe in the general context of the computer executable instructions of being carried out by computer, for example program module.Usually, program module comprises the routine carrying out particular task or realize particular abstract data type, program, object, assembly, data structure etc.Also can in distributed computing environment (DCE), put into practice the present invention, in these distributed computing environment (DCE), be executed the task by the teleprocessing equipment that is connected by communication network.In distributed computing environment (DCE), program module can be arranged in the local and remote computer-readable storage medium that comprises memory device.

For aforesaid each embodiment of the method, for simple description, therefore it all is expressed as a series of combination of actions, but those skilled in the art should know, the present invention is not subjected to the restriction of described sequence of movement, because according to the present invention, some step can adopt other orders or carry out simultaneously.Secondly, those skilled in the art also should know, the embodiment described in the specification all belongs to preferred embodiment, and related action and module might not be that the present invention is necessary.

At last, also need to prove, in this article, relational terms such as the first and second grades only is used for an entity or operation are separated with another entity or operating space, and not necessarily requires or hint and have the relation of any this reality or sequentially between these entities or the operation.And, term " comprises ", " comprising " or its any other variant are intended to contain comprising of nonexcludability, thereby not only comprise those key elements so that comprise process, method, commodity or the equipment of a series of key elements, but also comprise other key elements of clearly not listing, or also be included as the intrinsic key element of this process, method, commodity or equipment.In the situation that not more restrictions, the key element that is limited by statement " comprising ... ", and be not precluded within process, method, commodity or the equipment that comprises described key element and also have other identical element.

Above to a kind of antenna calibration method provided by the present invention and system, be described in detail, used specific case herein principle of the present invention and execution mode are set forth, the explanation of above embodiment just is used for helping to understand method of the present invention and core concept thereof; Simultaneously, for one of ordinary skill in the art, according to thought of the present invention, all will change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention.

Claims (10)

1. an antenna calibration method is characterized in that, comprising:

For each antenna in the aerial array, carry out the N secondary channel in the cycle at an antenna calibration and estimate, obtain each secondary channel and estimate the reflection antenna amplitude that obtains and the vector R of phase characteristic _k, wherein, N is positive integer, k=1, and 2 ..., ANT, ANT are total number of antenna;

For antenna k, judge successively the vector R that the estimation of i secondary channel obtains _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jWhether the vector that forms is pre-conditioned to satisfying, i=1, and 2 ..., N, j=1,2 ..., N;

Statistics satisfies the described pre-conditioned right number of vector;

According to satisfying effective vector that the described pre-conditioned right number of vector is determined described antenna k;

Calculate the calibration factor of antenna k according to described effective vector, and according to described calibration factor antenna k is calibrated.

2. method according to claim 1 is characterized in that, the described vector R that judges that successively the estimation of i secondary channel obtains _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jThe vector that forms comprises whether satisfying pre-conditioned step:

Compute vectors R _k ⁱWith vector R _k ^jDifference R _k ⁱ-R _k ^j

Judge described R _k ⁱ-R _k ^jAmplitude || R _k ⁱ-R _k ^j|| whether be less than or equal to R _k ⁱAmplitude || R _k ⁱ|| with default threshold T _ThresholdProduct;

If then determine vector R _k ⁱWith vector R _k ^jThe vector that forms is described pre-conditioned to satisfying, described vector R _k ⁱWith vector R _k ^jUnanimously.

3. method according to claim 2 is characterized in that, described foundation satisfies the described pre-conditioned right number of vector and determines that the step of effective vector of described antenna k comprises:

Estimate the vector R that obtains for the i secondary channel of antenna k _k ⁱ, obtain successively vector R _k ^jIn with vector R _k ⁱConsistent vector, more described and vector R _k ⁱThe number of consistent vector and the size of N/2;

As described and vector R _k ⁱThe number of consistent vector is determined described vector R during more than or equal to N/2 _k ⁱBe effective vector;

As described and vector R _k ⁱThe individual number average of consistent vector determines that described antenna k does not have effective vector during less than N/2.

4. method according to claim 3 is characterized in that,

When there was effective vector in antenna k, described antenna k was effective antenna;

When there was not effective vector in antenna k, described antenna k was invalid antenna;

When having invalid antenna in the aerial array, described method also comprises:

Obtain the vector R of described reference antenna m take any one effective antenna m wherein as reference antenna _mAmplitude and phase place, m=1,2 ..., ANT;

According to described vector R _mAmplitude and the phase place vector R that obtains successively antenna n in the aerial array _nCorresponding new vector R _n', n=1,2 ..., ANT;

For antenna n, according to described new vector R _n' judge whether antenna n exists effective vector;

If then calculate calibration factor, and according to described calibration factor antenna n calibrated;

If not, then obtain in the antenna calibration cycle and antenna n is calibrated the calibration result that obtains according to the calibration factor of antenna n, with the calibration result of described calibration result as this antenna calibration cycle internal antenna n.

5. method according to claim 4 is characterized in that, the described vector R of described foundation _mAmplitude and the phase place vector R that obtains successively antenna n in the aerial array _nCorresponding new vector R _n' step comprise:

Keep vector R _nAmplitude constant, with vector R _nDescribed vector R turns clockwise _mPhase place, obtain corresponding new vector R _n'.

6. an antenna calibration system is characterized in that, comprising:

The vector acquisition module is used for each antenna for aerial array, carries out the N secondary channel in the cycle at an antenna calibration and estimates, obtains reflection antenna amplitude that each secondary channel estimation obtains and the vector R of phase characteristic _k, wherein, N is positive integer, k=1, and 2 ..., ANT, ANT are total number of antenna;

The first vector is used for for antenna k judge module, judges successively the vector R that the estimation of i secondary channel obtains _k ⁱThe vector R that estimation obtains with the j secondary channel _k ^jWhether the vector that forms is pre-conditioned to satisfying, i=1, and 2 ..., N, j=1,2 ..., N;

Statistical module is used for statistics and satisfies the described pre-conditioned right number of vector;

Effectively the vector determination module is used for according to satisfying effective vector that the described pre-conditioned right number of vector is determined described antenna k;

The first calibration module is used for the calibration factor according to described effective vector calculating antenna k, and according to described calibration factor antenna k is calibrated.

7. system according to claim 6 is characterized in that, described the first vector comprises judge module:

Difference computational unit is used for compute vectors R _k ⁱWith vector R _k ^jDifference R _k ⁱ-R _k ^j

Judging unit is used for judging described R _k ⁱ-R _k ^jAmplitude || R _k ⁱ-R _k ^j|| whether be less than or equal to R _k ⁱAmplitude || R _k ⁱ|| with default threshold T _ThresholdProduct;

Determining unit, be used for when the judged result of judging unit when being, determine vector R _k ⁱWith vector R _k ^jThe vector that forms is described pre-conditioned to satisfying, described vector R _k ⁱWith vector R _k ^jUnanimously.

8. system according to claim 6 is characterized in that, described effective vector determination module comprises:

Comparing unit is for the vector R that estimates for the i secondary channel of antenna k to obtain _k ⁱ, obtain successively vector R _k ^jIn with vector R _k ⁱConsistent vector, more described and vector R _k ⁱThe number of consistent vector and the size of N/2;

First effective vector determining unit, the comparative result that is used for when comparing unit is described and vector R _k ⁱThe number of consistent vector is determined described vector R during more than or equal to N/2 _k ⁱBe effective vector;

Second effective vector determining unit, the comparative result that is used for when comparing unit is described and vector R _k ⁱThe individual number average of consistent vector determines that described antenna k does not have effective vector during less than N/2.

9. system according to claim 8 is characterized in that,

When there was effective vector in antenna k, described antenna k was effective antenna;

When there was not effective vector in antenna k, described antenna k was invalid antenna;

Described system also comprises:

Reference antenna vector acquisition module is used for when there is invalid antenna in aerial array, obtains the vector R of described reference antenna m take any one effective antenna m wherein as reference antenna _mAmplitude and phase place, m=1,2 ..., ANT;

New vector acquisition module is used for according to described vector R _mAmplitude and the phase place vector R that obtains successively antenna n in the aerial array _nCorresponding new vector R _n', n=1,2 ..., ANT;

The second vector is used for for antenna n judge module, according to described new vector R _n' judge whether antenna n exists effective vector;

The second calibration module, be used for when the second vector to the judged result of judge module when being, calculating calibration factor, and the described calibration factor of foundation is calibrated antenna n;

The calibration result determination module, be used for when the second vector when the determination result is NO to judge module, obtain in the antenna calibration cycle and antenna n is calibrated the calibration result that obtains according to the calibration factor of antenna n, with the calibration result of described calibration result as this antenna calibration cycle internal antenna n.

10. system according to claim 9 is characterized in that, described new vector acquisition module comprises:

Rotary unit is used for keeping vector R _nAmplitude constant, with vector R _nDescribed vector R turns clockwise _mPhase place, obtain corresponding new vector R _n'.

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