CN103780296A - Uniform circular array antenna signal receiving and distortion correcting method - Google Patents

Abstract

The invention relates to an uniform circular array antenna signal receiving and distortion correcting method. The method comprises the following steps: the step 1 in which the receiving link antenna array amplitude/phase gain matrix estimation is performed; the step 2 in which the receiving link antenna array mutual coupling coefficient matrix estimation is performed; the step 3 in which correction is performed on the receiving link according to the estimated receiving link antenna array amplitude/phase gain matrix and mutual coupling coefficient matrix; the step 4 in which the transmitting link antenna array gain matrix estimation is performed; and the step 5 in which amplitude/phase correction and mutual coupling correction are performed on the transmitting link through the estimated transmitting link gain matrix and receiving link mutual coupling coefficient matrix. Compared with the prior art, the method of the invention can be used to perform system-level correction on the receiving link and the transmitting link of the uniform circular array antenna, and has advantages, such as complete scheme, good correction effect, etc.

Description

A kind of signal of Homogeneous Circular array antenna receives and distortion antidote

Technical field

The signal that the present invention relates to smart antenna in the communications field receives and distortion correcting technology, and the signal that especially relates to a kind of Homogeneous Circular array antenna receives and distortion antidote.

Background technology

Along with the development of wireless mobile telecommunication technology; the demand of mobile communication is also growing; the restriction of radio network technique itself makes it can not continue to meet high communication need; user is in the time disposing WLAN; often have that wireless signal is disturbed, signal penetration capacity is poor, cause the short common problem of transmission range.Utilize the service efficiency of new technology raising finite frequency resource, become the problem of people's growing interest.

Beam forming is the combination of antenna technology and Digital Signal Processing, and object makes system can support more user in limited frequency spectrum for phasing signal transmission or reception, thereby increases exponentially frequency spectrum service efficiency.Beam forming technique is applied to phased array radar the earliest, forms narrow beam scan by multiple antenna elements, is applied to afterwards the communications field, is mainly used in the base station in civilian mobile communication.It is synthetic that its basic principle utilizes multi-antenna technology to be weighted reception Ge road signal, determines signal arrival bearing, and signal source is carried out to precise positioning, produces multipath high-gain orientation point wave beam, and outstanding degree of depth non line of sight function is provided.

In the time that system adopts array antenna, receive the impact that signal is subject to the amplitude/phase error of bay itself, distance between the unit of aerial array is less than 1/2nd wavelength conventionally simultaneously, make to there is stronger coupling between the array element of array antenna, this coupling can make transmitting and receiving of signal produce distortion, thereby the beam forming on antenna array and arrival bearing estimate to produce larger impact, make to receive distorted signals serious, impact to a great extent the performance of beam forming receiver.Therefore, obtain the mutual coupling coefficient of antenna array by calculating or experiment measuring, the mutual coupling rectification of carrying out according to this software or hardware has very important significance.And the key foundation of carrying out mutual coupling rectification is the mutual coupling compensation coefficient matrix between array element.

At present more domestic and international scholars are just being devoted to the research of array error antidote, and the antidote proposing is mainly divided into from antidote and the large class of active antidote two.Active antidote is by spatial placement orientation, accurate known auxiliary information source pair array error parameter carries out off-line estimation; Provide the estimated value in array error parameter and information source orientation from antidote simultaneously.Although from antidote without the auxiliary source by known location, and then also without overcoming the uncertain factor of carrying in auxiliary source signal, conventionally process very complicated, higher to the requirement of real-time of algorithm.In numerous active antidotes, See CMS etc. are at IEE Proceedings-Radar, the document method forarray calibration in high-resolution sensor array processing of Sonar and Navigation has proposed a kind of for array element mutual coupling, the active correction algorithm of the array errors such as amplitude phase error, this algorithm is decomposed and is obtained one group and correct the direction vector in source and estimate array error by matrix character, in order to simplify the discussion of problem, the document is also made the product of mutual coupling matrix and amplitude phase error matrix as a wholely to estimate, but algorithm does not make full use of DOA estimates the impact on estimation of mutual coupling coefficient, iterative process cannot separate interweaving of DOA error and mutual coefficient errors, computational process still has redundancy.

Summary of the invention

Object of the present invention is exactly to provide a kind of signal of Homogeneous Circular array antenna to receive and distortion antidote in order to overcome the defect that above-mentioned prior art exists, can carry out system-level rectification to the reception of uniform circular array, transmitting chain, scheme is complete and rectification effect good.

Object of the present invention can be achieved through the following technical solutions:

The signal of Homogeneous Circular array antenna receives and a distortion antidote, it is characterized in that, comprises the following steps:

Step 1: the amplitude/phase gain matrix of receiver antenna array is estimated;

Step 2: the mutual coefficient matrix of receiver antenna array is estimated;

Step 3: receiver is corrected according to amplitude/phase gain matrix and the mutual coefficient matrix of the receiver antenna array of estimating;

Step 4: the gain matrix of transmitting chain antenna array is estimated;

Step 5: utilize the gain matrix of transmitting chain and the mutual coefficient matrix of receiver estimated, transmitting chain is carried out to amplitude/phase rectification and mutual coupling rectification.

Utilize near-field coupling antenna and rectification source, far field, successively to receiving amplitude/phase gain matrix and the mutual coefficient matrix of link antennas battle array.

The mutual coefficient matrix C of described receiver antenna array estimates to be specially:

Mutual coefficient matrix C is estimated to be reduced to the estimation that mutual coupling matrix is characterized to vectorial c,

If n=2k+1 (k=1,2 ...), c={1 c ₁c ₂c _kc _kc ₂c ₁;

If n=2k (k=1,2 ..), c={1 c ₁c ₂c _k-1c _kc _k-1c ₂c ₁.

Wherein c _i(i=1,2 ..., k) for to center of circle differential seat angle being the (coupling coefficient between two array elements of the i of 2 π/n); N is circular antenna array element number, and k is corresponding independent element number.

Described corrects and is specially receiver:

First carry out amplitude/phase gain error correction, then utilize DOA estimated result to estimate mutual coefficient matrix, the signal after rectification

wherein Y _{n × s}for actual signal, the C of receiving of circle battle array _{n × n}for the mutual coefficient matrix of n unit circle battle array, G _{n × n}for gain error matrix.

, amplitude/phase is corrected and mutual coupling rectification is specially in described transmitting chain is carried out:

If antenna array intends transmitting X, before transmitting, carry out width phase, mutual coupling error correction, actual transmission signal is $X^{\′}={G_t}^{-1}{C}^{-1}X,$ After correcting, actual emanations to the signal in far field is $Y=\mathrm{AC}{G}_t{X}^{\′}={\mathrm{ACG}}_t{G_t}^{-1}{C}^{-1}X=\mathrm{AX},$ Wherein A is that direction vector, C are mutual coefficient matrix, the G of circle battle array _tfor transmitting chain gain error matrix.

Compared with prior art, the invention provides a set of complete Homogeneous Circular aerial array transmitting chain, receiver distorted signals antidote, form a loop correction system, it both can carry out distortion rectification to the receiver of antenna array, again the estimation of the mutual coupling coefficient is applied in transmitting chain, transmitting chain is carried out to distortion rectification, and the auxiliary source of its utilization is few, accuracy of estimation is high.

Accompanying drawing explanation

Fig. 1 is the array antenna structure schematic diagram that the present invention applies;

Fig. 2 is workflow diagram of the present invention.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.

Embodiment

The present embodiment is implemented under take technical solution of the present invention as prerequisite, provided detailed execution mode and concrete operating process, but protection scope of the present invention is not limited to following embodiment.

As shown in Figure 1, take the Homogeneous Circular array antenna of 15 array elements as example, all array element is half-wave antenna, is operated under 5GHz frequency circle battle array λ/2, radius R=6 π.Reception, transmitting chain distortion antidote comprise the following steps:

Step 1: correcting signal source, near field is located to the circle centre position of Homogeneous Circular array antenna, is corrected source transmitted signal z _{1 × m}={ z ₁, z ₂..., z _m, m is for correcting sequence length, antenna receiving signal

y _i(i=1 ... 15) be the reception burst of i array element.Amplitude/phasing matrix G _{15 × 15}=diag{g}, g={1 g ₂g ₃... g ₁₅, near field is corrected and is estimated amplitude/phase coefficient g _i=avg{y _i./y ₁, i=2,3...15; Use g _ireconstruct amplitude/phasing matrix G _{15 × 15}=diag{1 g ₂g ₃... g ₁₅;

Step 2: far-field signal source transmitted signal sequence x _{1 × s}, carry out to received signal amplitude/phase error and correct, will receive signal Y ' _{15 × s}the inverse matrix of matrix premultiplication amplitude/phasing matrix, the signal battle array after being corrected

$Y_{15\×s}=G_{15\×15}^{-1}{Y}_{15\×s}^{\′}=\mathrm{diag}\left\{\begin{array}{ccccc}1& g_2^{-1}& g_3^{-1}& ...& g_{15}^{-1}\end{array}\right\}{Y}_{15\×s}^{\′}$

Utilize DOA algorithm to Y _{15 × s}do direction of arrival and estimate, obtain estimating angle information θ, according to the topological structure of angle information and Homogeneous Circular array, calculate direction vector A _{15 × 1}(θ).

To receive signal matrix Y _{15 × s}to the reception signal of the first array element carry out relevant,

relevant R to received signal _ywith direction vector A _{15 × 1}(θ) do respectively discrete Fourier transform, then two frequency domain vector that generate are put and removed, obtain the sign vector c ' of coupling matrix on frequency domain

c′＝FFT[R _y]./FFT[A _15×1(θ)]

Coupling matrix C _{15 × 15}be the symmetrical toeplitz matrix with cycle characteristics, and diagonal entry is 1.C _{15 × 15}can characterize with its first row/column c,

c＝{1?c ₁?c ₂?…?c ₇?c ₇?…?c ₂?c ₁}；

Wherein c _i(i=1,2 ..., 7) for to center of circle differential seat angle being the (coupling coefficient between two array elements of the i of 2 π/n).

Coupling coefficient frequency domain is characterized to vectorial c ' to be done Fourier inversion and obtains c ", c "=c " ₁c " ₂c " ₁₅, by c " first component normalization of vectorial basis, obtains the sign vector c of symmetrical toeplitz coupling matrix,

c″＝IFFT(c′)

c＝c″/c″ ₁

Utilize c reconstruct to obtain mutual coefficient matrix C _{15 × 15}.

Step 3: according to width/phase gain matrix and mutual coefficient matrix, receiver is corrected,

${Y^{\′}}_{n\×s}=C_{n\×n}^{-1}{G}_{n\×n}^{-1}{Y}_{n\×s}.$

Step 4: transmitting chain circular antenna sends m group snap vector for a specific k (k=1,2...15), the component x of vector _i

$x_i=\left\{\begin{array}{cc}1& i=k\\ 0& i\≠k\end{array}\right.$

Order for m group x ^k, obtain

mean value, thereby can obtain the estimated value of transmitting terminal width phase gain matrix $G_t=\mathrm{diag}\left\{\begin{array}{ccccc}1& g_{t_2}& g_{t_3}& ...& g_{t_n}\end{array}\right\}.$

Step 5: transmitting of antenna array corrected.If antenna array intends transmitting X, should before transmitting, carry out width phase, mutual coupling error correction, actual transmission signal is

like this, actual emanations to the signal in far field is $Y=\mathrm{ACG}{X}^{\′}={\mathrm{ACG}}_t{G_t}^{-1}{C}^{-1}X=\mathrm{AX}.$

Claims (5)

1. the signal of Homogeneous Circular array antenna receives and a distortion antidote, it is characterized in that, comprises the following steps:

Step 1: the amplitude/phase gain matrix of receiver antenna array is estimated;

Step 2: the mutual coefficient matrix of receiver antenna array is estimated;

Step 3: receiver is corrected according to amplitude/phase gain matrix and the mutual coefficient matrix of the receiver antenna array of estimating;

Step 4: the gain matrix of transmitting chain antenna array is estimated:

Step 5: utilize the gain matrix of transmitting chain and the mutual coefficient matrix of receiver estimated, transmitting chain is carried out to amplitude/phase rectification and mutual coupling rectification.

2. a kind of signal according to claim 1 receives and distortion antidote, it is characterized in that, utilizes near-field coupling antenna and rectification source, far field, successively to receiving amplitude/phase gain matrix and the mutual coefficient matrix of link antennas battle array.

3. a kind of signal according to claim 1 receives and distortion antidote, it is characterized in that, the mutual coefficient matrix C of described receiver antenna array estimates to be specially:

Mutual coefficient matrix C is estimated to be reduced to the estimation that mutual coupling matrix is characterized to vectorial c,

If n=2k+1 (k=1,2 ...), c={1 c ₁c ₂c _kc _kc ₂c ₁;

If n=2k (k=1,2 ..), c={1 c ₁c ₂c _k-1c _kc _k-1c ₂c ₁.

Wherein c _i(i=1,2 ..., k) for to center of circle differential seat angle being the (coupling coefficient between two array elements of the i of 2 π/n); N is circular antenna array element number, and k is corresponding independent element number.

4. a kind of signal according to claim 1 receives and distortion antidote, it is characterized in that, described corrects and be specially receiver:

First carry out amplitude/phase gain error correction, then utilize DOA estimated result to estimate mutual coefficient matrix, the signal after rectification

wherein Y _{n × s}for actual signal, the C of receiving of circle battle array _{n × n}for the mutual coefficient matrix of n unit circle battle array, G _{n × n}for gain error matrix.

5. a kind of signal according to claim 1 receives and distortion antidote, it is characterized in that, amplitude/phase is corrected and mutual coupling rectification is specially in described transmitting chain is carried out:

If antenna array intends transmitting X, before transmitting, carry out width phase, mutual coupling error correction, actual transmission signal is X '=C _t ^-1c ^-1x, after correcting, actual emanations to the signal in far field is

wherein A is that direction vector, C are mutual coefficient matrix, the G of circle battle array _tfor transmitting chain gain error matrix.

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