45 results about "Coprime array" patented technology

The present invention discloses a Vandermonde decomposition-based coprime array direction of arrival estimation method. The invention aims to solve the problem that degree-of-freedom performance is limited, and the problem of high computational complexity in the prior art. The implementation process of the method includes the following steps that: a receiving antenna is constructed into a coprime array structure; the coprime array is utilized to receive incident signals and perform modeling; equivalent virtual signals corresponding to the signals received by the coprime array are calculated; a virtual array covariance matrix is constructed; de-noising processing is performed on the virtual array covariance matrix; uniqueness Vandermonde decomposition is performed on the de-noised virtual array covariance matrix; and parameters which are obtained through the Vandermonde decomposition are made to correspond to theoretical values, so that direction of arrival and power estimation results can be obtained. According to the Vandermonde decomposition-based coprime array direction of arrival estimation method of the invention adopted, the coprime array is fully utilized, so that degree-of-freedom performance can be improved; according to the Vandermonde decomposition, grid points are not required to be preset, and therefore, computational complexity can be decreased, and at the same time, the degree of freedom of the direction of arrival estimation method can be increased. The direction of arrival estimation method can be applied to passive positioning and target detection.

Disclosed is a coprime array adaptive beamforming method based on a virtual domain spatial power spectrum estimation, mainly solving a problem of limited degree of freedom (DOF) performance in the prior art. The coprime array adaptive beamforming method based on the virtual domain spatial power spectrum estimation comprise: (1) a coprime array is constructed by a base station; (2) the coprime array is used to receive signals and modelling is performed; (3) an equivalent receipt signal of a virtual array is obtained; (4) a virtual domain spatial power spectrum of the coprime array is calculated; (5) a desired signal steering vector is reconstructed; (6) an interference and noise covariance matrix is obtained by integral reconstruction; and (7) a weight vector of a beamformer is calculated. The invention takes full advantage of an ability of the coprime array to increase a DOF so that a spatial power spectrum is calculated in a virtual domain to perform a parameter estimation and a physical antenna array element weight vector of the coprime array is designed by combining an idea of reconstruction, thereby effectively improving the DOF performance of the beamformer. The invention can be used in directed transmission and receipt of signals.

The invention discloses a virtual wave beam forming method based on coprime arrays. The method comprises the steps of: firstly, arranging a plurality of array elements to form the coprime arrays, and carrying out multi-snapshot sampling on incident signals of a plurality of non-relevant signal sources in different spatial directions; carrying out time averaging estimation on correlation function values different in correlation space; then based on corresponding relations between correlation spaces and coprime array difference cooperation array virtual array element positions, extracting the correlation function values having the continuous correlation spaces, and constructing equivalent single-snapshot signals of virtual array elements uniformly distributed in difference cooperation arrays; and finally, according to the position distribution of the uniformly distributed virtual array elements, designing weight vectors, and carrying out weighted superposition on the equivalent single-snapshot signals so as to obtain output wave beams. According to the invention, the characteristic that most virtual array elements are uniformly distributed in the difference cooperation arrays of the coprime arrays is utilized to solve the problems of an existing sparse subarray wave beam multiple multiplication method that sidelobe interference exists and the method is not suitable for a plurality of signal sources, the wave beam signal to noise ratio is effectively increased, and the noise resistance is improved.

The invention discloses a dual-layer-hybrid-array-based estimation method for a direction angle of arrival. With the method, problems of high operation load, a few of identification signal sources, and large estimation error in the prior art can be solved. The method comprises the following steps: (1), a one-layer coprime array and a two-layer nesting array are constructed respectively; (2), an output signal of the one-layer coprime array and an output signal of the two-layer nesting array are obtained; (3), on the basis of the output signal of the one-layer coprime array and the output signal of the two-layer nesting array, all four-order cumulants are calculated to form a four-order cumulant vector; (4), according to the four-order cumulant vector, an over-complete base is constructed and an airspace sparse vector is defined; (5), detection airspace direction-angle-of-arrival estimation is converted into sparse constraint equation solving; (6), with a convex optimization method, a sparest solution of an airspace sparse vector is obtained; and (7), an amplitude spectrogram is drawn based on the sparest solution and a direction angle of arrival is obtained. According to the method provided in the invention, the signal source number with identifiable arrays increases substantially under the circumstance that the array element number is limited. The method is suitable for target scouting and passive location.

The invention discloses a planar array DOA estimation method and equipment thereof. The planar array DOA estimation method comprises the following steps of 1, receiving a signal from at least one signal source by means of a planar array, wherein the planar array comprises at least one parallel coprime array, and the parallel coprime array comprises coprime linear subarray pairs which are parallelwith each other; 2, based on an actually received signal of the coprime linear subarray pairs, calculating an autocovariance matrix of actually received signals of two linear subarrys of the coprime linear subarray pairs, and a cross-covariance matrix between the actually received signals of the two linear subarrys; and 3, estimating the DOA value of at least one signal source based on the autocovariance matrix and the cross-covariance matrix. The planar array DOA estimation method and the equipment thereof settle a problem of high algorithm complexity caused by factors such as two-dimensionalspatial spectrum searching and angle pairing and can realize high-precision wave arrival direction estimation with relatively low complexity. The method and the equipment are suitable for the occasion with high real-time performance requirement.

The invention provides a coprime array wave arrival direction angle estimation method based on variable-decibel bayesian inference; receiving and sampling are performed on spatial signals by utilizingthe coprime array, and a sparse model vector is constructed according to the sampling covariance matrix; the wave arrival angle estimation problem is converted into a sparse reconstruction problem ina linear model, and an amplitude spectrogram is drawn; and an x-axis coordinate corresponding to the peak point is searched from the amplitude spectrogram, namely, the obtained wave arrival directionangle estimation value. The angle searching or angle matching process of the traditional method is avoided, meanwhile, the sampling frequency can be lower than the nyquist sampling rate, and better estimation performance can be obtained under the condition of a low snapshot number, so that the model dimension is greatly reduced, the calculation amount and the sparse reconstitution speed are improved, direct solution in the complex distribution form is avoided, the algorithm complexity is reduced, and the algorithm convergence speed is improved.

The invention relates to a coprime array-to-uniform linear array conversion-based DOA (Direction of Arrival) estimation method and device. The method includes the following steps that: array element positions are arranged in an ascending order according to a coprime array model, differencing processing is performed on any two array element positions, so that a delay set is obtained, and a difference set table is formed; the difference set is traversed, all coordinates requiring delay are found out in a sparse covariance matrix, corresponding covariance function values are subjected to statistical averaging, autocorrelation function values requiring delay are calculated; a Toepltz matrix is constructed according to the autocorrelation function values, element values on diagonals parallelto the main diagonal of the Toepltz matrix are identical; and a spatial spectrum search function is constructed based on the MUSIC algorithm, the Toepltz matrix is solved, when a spatial spectrum search vector is consistent with a signal steering vector, a correct DOA estimation value is found out. The device includes an external RAM, a digital signal processor, and an output driving and display circuit. The method and device of the present invention do not require a multiplier and are simple in operation, can achieve the same effect as a spatial smoothing matrix, and can greatly reduce the degrees of freedom.

The invention provides a coprime matrix robust adaptive beamforming algorithm based on matrix filling. The coprime matrix robust adaptive beamforming algorithm based on matrix filling comprises the following steps that a sample covariance matrix of received data is calculated; the sample covariance matrix is vectorized to obtain vectors, and then elimination of redundancy and vector rearrangementare carried out on the vectors to obtain the received data vectors of a complete coprime matrix differential optimization matrix; zero is arranged between elements with discontinuous wave range difference in the received data vectors in a filling mode to obtain the vectors, and then the vectors are obtained by taking information of the positive half part of the vectors; the vectors are expanded into a Toplitz matrix; the Toplitz matrix is restored to obtain a filled covariance matrix; spectral peak search is carried out in an interference signal angle region to obtain estimation of arrival angles of each interference signal; the estimated arrival angles of interference signals, the physical array information of a coprime array and an interference and noise covariance matrix which reconstructs a coprime array physical array are utilized; weighted vectors of an adaptive beamformer is calculated by using the estimation of the interference and noise covariance matrix and expected signal steering vectors.

The invention discloses an adaptive beam forming method based on a coprime array and mainly solves the problems that the existing technology cannot fully utilize the characteristics of the coprime array and the output performance degrades. The method comprises the following implementation steps of (1) structuring the coprime array on a base station end; (2) decomposing the coprime array into a pair of coprime sparse uniform linear subarrays; (3) utilizing receiving signals of the decomposed coprime sparse uniform linear subarrays to carry out direction of arrival estimation; (4) constructing power estimation based on joint optimization of a covariance matrix of the pair of coprime sparse uniform linear subarrays; (5) reconstructing an expected signal steering vector; (6) reconstructing an interference and noise covariance matrix; and (7) designing a beam forming weight vector. The method fully utilizes the coprime characteristics included by the coprime array to realize the precise parameter estimation and reconstructs major parameters of the beam forming weight vector, so that the output performance of an adaptive beam former is effectively improved and the method can be used for directional sending and reception of a signal.

The invention discloses a coprime array DOA estimation method based on a quantum penguin search mechanism under strong impact noise. The method comprises the following steps: obtaining a fractional low-order covariance matrix of an infinite norm weighted signal; constructing an extended fractional low-order covariance matrix and an extended guide matrix, and constructing a maximum likelihood direction finding equation based on the extended covariance matrix; initializing a quantum penguin group, and initializing the speed and the quantum position of the quantum penguin; calculating fitness andcarrying out descending sort, and selecting a global optimal quantum position; updating the quantum position of the quantum penguin; evaluating a quantum penguin position fitness value, and updatinga global optimal quantum position; judging whether the maximum number of iterations is reached or not, and if not, continuing iteration; and if so, outputting a global optimal quantum position, and mapping to obtain an optimal DOA estimation value. According to the invention, higher direction finding precision, higher operation speed, better array aperture expansion capability, coherent source measurement capability, impact noise resistance and wider application environment are realized.

The invention provides a Coprime array robust adaptive beam forming method based on matrix reconstruction, which fully utilizes the characteristic of large virtual aperture of a Coprime array sparse array, estimates the angles of signals and interference in a virtual domain, estimates the power of the signals and the interference by utilizing the corresponding relation between noise power and a covariance matrix, and realizes the reconstruction of INCM. When the Coprime array is configured as follows: array element numbers of two sub-arrays are 2M<1> and M<2> respectively, the array element spacing is M<2>d and M<1>d, d is the minimum array element spacing, when an SERB algorithm is applied, the degree of freedom of interference suppression is min{2M<1>-1, M<2>-1}, and the degree of freedom of interference suppression of the algorithm in the Coprime array is 2M<1>+M<2>-2 which is obviously higher than the degree of freedom of interference suppression of the SERB algorithm.

The invention discloses a beam forming method and device based on a vector extended co-prime array. The method comprises the following steps: step 1, on the premise that the array element number of a vector array needs to be set, coprime array element number initial values M and N are drawn up for an underwater acoustic vector array of a specified physical array element; 2, according to the sub-array beam output zero point and grating lobe position characteristics of the co-prime array, an array expansion factor is set, and an initial co-prime array element pair is expanded; 3, changing a sub-array data channel combination by using a sound pressure and vibration velocity combined processing method to reduce array beam output grating lobes; 4, an array weighting factor based on sound pressure and vibration velocity combined processing is set to further reduce beam output side lobes; and step 5, obtaining final vector extension co-prime array beam output spatial spectrum synthesis by using co-prime array beam forming. According to the invention, the extended co-prime vector array beam output with low grating lobe, low side lobe and narrow main lobe can be obtained.