55 results about "Coprime array" patented technology

The invention discloses a DOA (Direction of Arrival) estimation method and system based on a deep complex value convolution attention residual network, belongs to the technical field of array signal processing, and solves the technical problems of low precision and poor robustness of the existing DOA estimation method under the severe conditions of low signal-to-noise ratio, limited snapshot number and the like. The method comprises the following steps: acquiring data by using a co-prime array and preprocessing to obtain SCM data as original input information of DOA estimation; constructing a deep complex value convolution attention residual network to directly process covariance matrix information of a complex field, and utilizing an initial two-dimensional complex value convolution layer, a cascaded complex value convolution block attention network and a cross-layer residual connection structure to deeply extract complex value features related to a space angle; the DOA estimation module is responsible for finally mapping the extracted high-dimensional complex value feature vector to a representation space directly related to a DOA estimation task, and the output module converts the internal feature representation output by the DOA estimation module into a DOA estimation result which can be explained by a user.

The invention belongs to the technical field of array signal processing, and particularly relates to a co-prime array design method based on virtual array hole filling, which comprises the following steps of: S1, forwards moving two sub-arrays of an extended co-prime array by a distance of Nd / 2; s2, turning over one sub-array of the shifted co-prime array to obtain an improved co-prime array; s3, generating a differential virtual array according to the improved co-prime array; s4, introducing and combining the array to carry out hole filling on the differential virtual array; s5, calculating a received signal model and a covariance matrix of the filled virtual array; and S6, DOA estimation is carried out by using an ROOT-MUSIC algorithm. The method has the advantages that better signal source resolution and lower array element mutual coupling are achieved, meanwhile, the continuous freedom degree is improved, more signal sources can be estimated at the same time, and high practical value is achieved.

The invention discloses a low-redundancy high-order direction finding method and system based on co-prime characteristics and a computer storage medium, and the method comprises the steps: receiving signals from a plurality of signal sources through employing a low-redundancy array obtained through improvement based on a co-prime array, and obtaining a received signal; calculating a fourth-order cumulant matrix of the received signal according to the received signal; obtaining a covariance matrix according to the fourth-order cumulant matrix; according to the covariance matrix, calculating to obtain a characteristic value and a characteristic vector of the covariance matrix; dividing the feature vector into a signal subspace and a noise subspace according to the size of the feature value; constructing a spectral function according to the projection of the steering vector on the noise subspace; and searching peak values of the spectral function in all possible directions, and determining the direction of the signal source. According to the low-redundancy array obtained based on improvement of the co-prime array, on the basis that the number of receiving array elements is reduced, the number of estimated signal sources is increased, the fourth-order cumulant is adopted, and the positioning precision in a non-Gaussian noise environment can be improved.

The application discloses a two-dimensional coherent signal DOA estimation method based on double parallel relatively prime array movement, which comprises the following steps: a double parallel array comprises a first subarray and a second subarray, phase compensation is performed on the output of the first subarray and the output of the second subarray to obtain first subarray compensation output and second subarray compensation output; a first vector is obtained based on the first subarray compensation output and the second subarray compensation output, and a second vector is obtained based on the first subarray compensation output; a sparse off-grid optimization function is constructed; accurate angle estimation of an incident signal and an X axis is obtained based on the sparse off-grid optimization function; angle estimation of the incident signal and a Y axis is obtained based on the first vector and the second vector; and angle estimation value of the two-dimensional coherent signal is obtained based on the accurate angle estimation of the incident signal and the X axis and the angle estimation of the incident signal and the Y axis. The application uses the double parallel relatively prime array to perform angle estimation of the two-dimensional coherent signal, and makes up for the deficiency of the relatively prime array in angle estimation of a coherent source.

The invention discloses a V-shaped co-prime array two-dimensional direction finding method and system based on array transformation. According to the method, firstly, array improvement is carried out on the basis of a traditional co-prime array; secondly, receiving a signal through an array antenna of a sparse array structure after array improvement, and obtaining a noise subspace through covariance matrix solving and eigenvalue decomposition; and finally, constructing a MUSIC spectral function, searching to obtain a joint pitch angle and an azimuth angle based on the noise subspace, and finally calculating a DOA estimated value of the information source. The array structures VCACS and VCACSS provided by the invention have a larger degree of freedom and fewer array elements to carry out two-dimensional parameter estimation, so that the azimuth angle and the elevation angle do not influence each other when the azimuth angle and the elevation angle are estimated respectively, and the estimation result is more accurate.

According to the method for searching the underwater object by using the ultra-short baseline of the L-shaped co-prime array, a ship or an aircraft travels and is berthed in a water surface area near the underwater object or on the water surface area, a coordinate system is established by taking a certain point of the ship or the aircraft as a coordinate origin, a base station is arranged on the origin, N + M-2 array elements are respectively arranged on an X axis and a Y axis, N and M are both prime numbers, and M is a prime number; the included angle between the underwater object and the X axis is alpha, the included angle between the underwater object and the Y axis is beta, the included angle between the underwater object and the Z axis is psi, the position of the underwater object in a coordinate system is (X, Y, Z), and the method for searching the underwater object by using the ultra-short baseline of the L-shaped co-prime array comprises the following steps: transmitting and receiving acoustic signals; determining a distance; constructing a received signal model; determining an incident angle to obtain alpha, beta and psi; calculating the position of the underwater object: X = Rcos alpha; y is equal to Rcos beta; according to the invention, the large aperture of the sparse array and the advantages of small array size and convenient installation of the ultra-short baseline positioning system are fully utilized.

A two-dimensional DOA estimation method for coprime arrays based on a combination of compressed sensing and minimization processing first decomposes the coprime array into two sparse sub-arrays and establishes a data model for each sub-array. Compressed sensing is then introduced, and a compressed sensing kernel is constructed to compress and project the received data of the sub-arrays to obtain the contour signals of the sub-arrays after dimensionality reduction. The contour signals of the sub-arrays are then processed using a DOA estimation algorithm to obtain a two-dimensional spatial spectrum estimate of the sub-arrays. Finally, a minimum processing method is used to combine the two-dimensional DOA estimation results of the sub-arrays to eliminate angular ambiguity and obtain a two-dimensional DOA estimation result for the coprime arrays. The present invention introduces compressed sensing into the traditional two-dimensional DOA estimation method for coprime arrays, reducing data dimensionality, data storage space, and computational complexity. At the same time, the minimum processing method is combined to eliminate angular ambiguity, eliminating the need to sequentially compare the spectral peaks of the sub-arrays and further simplifying the calculation.

Provided are a signal transmission method, a communication apparatus, a storage medium and a program product. The method comprises: determining array elements in a coprime array, wherein the array elements in the coprime array are some array elements in an antenna array of a first communication apparatus; and on the basis of hybrid beamforming, transmitting a first signal by means of the coprime array. The coprime array can achieve a larger virtual aperture by means of fewer physical array elements, or in other words, the number of equivalent virtual array elements is usually greater than the number of physical array elements. In this way, a transmitter of the first signal can use fewer array elements to implement beamforming of more signals; and a receiver of the first signal can use fewer array elements to implement DOA estimation of more signals, thereby improving the degrees of freedom of DOA estimation.

The invention discloses a co-prime array coherent source DOA (Direction of Arrival) estimation method aiming at a low signal-to-noise ratio and a small sample number, and relates to a subsurface buoy for ocean observation and a target detection processing method of a mobile observation platform. Specifically, coprime array output is converted into virtual array output, then an interpolation covariance matrix is obtained, then a covariance matrix is constructed by using a non-zero column, and an augmented covariance matrix is recovered through atom norm optimization. And finally, realizing coprime array coherent source DOA estimation under the condition of low signal-to-noise ratio and small sample number by using a coprime array PM algorithm. Compared with a traditional method, the method has the advantages that effective DOA estimation of the coherent source under the co-prime array condition is achieved, the DOA estimation precision is improved in the complex environment with the low signal-to-noise ratio and the small sample number, and the method has important application value in actual engineering.

The application discloses a DOA and Doppler frequency joint calculation method under unequal time domain parameter space-time coprime sampling, belongs to the field of signal processing, and is particularly aimed at the joint estimation of a direction of arrival and a Doppler frequency under the condition that physical resources are limited, and is suitable for joint coprime sampling and optimization of a space array and a time sequence. In the scheme, a coprime array is used in the space domain, coprime sampling is performed in the time domain, and different time domain coprime parameters are allowed to be selected at each antenna. Through the scheme, a larger virtual aperture is generated under the condition that the number of antennas and the number of sampling points are limited, so that the degree of freedom and the estimation resolution are improved.

The application discloses a low-redundancy high-order measurement direction method and system based on the coprime characteristic and a computer storage medium, and the method comprises the following steps: receiving signals from multiple signal sources by using a low-redundancy array improved based on a coprime array to obtain received signals; calculating a fourth-order cumulant matrix of the received signals according to the received signals; obtaining a covariance matrix according to the fourth-order cumulant matrix; calculating eigenvalues and eigenvectors of the covariance matrix according to the covariance matrix; dividing the eigenvectors into a signal subspace and a noise subspace according to the sizes of the eigenvalues; constructing a spectral function according to projections of the steering vectors on the noise subspace; searching for peak values of the spectral function in all possible directions to determine the directions of the signal sources. The low-redundancy array improved based on the coprime array can not only expand the estimated number of signal sources on the basis of reducing the number of received array elements, but also adopt the fourth-order cumulant, so that the positioning precision in a non-Gaussian noise environment can be improved.

This invention belongs to the field of information and marine technology, and discloses a method for estimating the DOA (Direction of Aperture) of a UUV (Ultra-UV) hull-side array using conjugate enhancement and virtual extension. This method performs conjugate enhancement processing on the received signal from a parallel coprime array, calculates the augmented statistical matrix including autocorrelation, conjugate autocorrelation, cross-correlation, and conjugate cross-correlation, and constructs an extended correlation matrix through weighted combination. A virtual uniform linear array is constructed using the differential co-array characteristics of the coprime array. A redundant integration matrix is ​​designed to remove redundancy from the covariance matrix, obtaining the equivalent signal of the virtual array. Then, the covariance matrix of the virtual array with a Toeplitz structure is reconstructed. Finally, a dual rotation-invariant subspace algorithm is used to achieve high-precision, automatic pairing estimation of the underwater target's azimuth and pitch angles. This invention extends the array aperture, improves the estimation robustness in low signal-to-noise ratio environments, and eliminates the need for spectral peak search, providing technical support for UUV underwater target positioning.

This invention relates to an improved spatially smoothed source angle estimation method and apparatus based on a coprime linear array. The method includes: acquiring a signal from a source under test using an augmented coprime array to obtain a received signal; vectorizing the covariance matrix of the received signal, sorting the resulting vectors according to the element positions of the uniform linear array, and processing them according to a data processing strategy to obtain a virtual signal received by a virtual array; uniformly dividing the virtual array into overlapping virtual subarrays based on a pre-constructed spatial smoothing rule, and calculating the spatial smoothing covariance matrix of the received signals from the virtual subarrays; performing eigenvalue decomposition on the spatial smoothing covariance matrix using a predefined spatial spectrum estimation method to obtain a spatial spectrum function; and performing spectral peak search on the spatial spectrum function to determine the source angle of the source under test. The method provided by this invention improves the array degrees of freedom and the accuracy of source angle estimation by constructing a larger number of virtual array elements.

The purpose of this invention is to provide a method for DOA estimation of acoustic vector arrays based on quaternion matrix dimensionality reduction, comprising the following steps: constructing a CAACIS acoustic vector coprime array at the receiver; establishing a quaternion model of the received signal based on the array output; estimating the quaternion covariance matrix; performing dimensionality reduction on the quaternion covariance matrix to obtain a virtual array received signal model of the acoustic vector coprime array; reconstructing the Hermitian-Toeplitz matrix; performing eigenvalue decomposition on the Hermitian-Toeplitz matrix and constructing a spatial spectral function; and obtaining the DOA estimation result through spectral peak search. This invention addresses the problem of how to achieve multi-objective DOA estimation with both low complexity and good performance based on a quaternion framework under acoustic vector coprime arrays.

The invention belongs to the technical field of array signal processing, and provides an extended co-prime array optimization method based on hole-driven greedy complementary points. The method comprises the following steps: S1, constructing an extended co-prime array, and selecting co-prime pairs (M, N) to generate a sub-array I and a sub-array II; s2, translating the sub-array 2, and determining a unique optimal shift amount through a comprehensive evaluation function; s3, turning over the second sub-array on the basis, extracting a hole set in the virtual differential array, adopting a greedy strategy to gradually supplement points to improve the center continuous degree of freedom, and controlling the number of newly added array elements through a parameter K; and S4, when the number of iterations reaches K or the complementary points are invalid, ending and outputting a final array structure. S5, performing direction of arrival estimation by using a spatial spectrum estimation algorithm under the ideal and coupled model; according to the method, the center continuous interval of the virtual array can be obviously expanded under the condition of limited physical array elements, the structure utilization rate and the array performance are improved, the accuracy and stability of direction-of-arrival estimation are improved, and the method has high engineering application value.

A method and a device for constructing a redundancy-removed coprime radar array based on one-bit quantization. The method includes obtaining a first sub-array element and a second sub-array element both used for constructing a redundancy-removed coprime radar array, and determining a redundancy-removed coprime array respectively corresponding to the first sub-array element and the second sub-array element by a graph theory method; obtaining target echo data of the redundancy-removed coprime array, and obtaining a target radar array by performing one-bit quantization on the target echo data for completing array cavities of the redundancy-removed coprime array; moreover, before the completing, positions of all non-empty array elements in a redundancy coprime array are used to place radars, and before the completing, the radars are not arranged in positions of empty array elements.

The invention discloses an efficient DOA estimation algorithm based on an expanded co-prime array, and the algorithm comprises the steps: enabling K narrowband far-field information sources to transmit narrowband far-field signals at the same time, enabling the narrowband far-field signals to enter the expanded co-prime array, carrying out the T times of snapshot number sampling of the expanded co-prime array, and enabling the received signal vector of the expanded co-prime array obtained during the tth time of snapshot number sampling to be x (t); respectively calculating UnUnH and a (theta k); k roots zk are obtained by using a Root MUSIC algorithm; and calculating K initial DOA estimated values # imgabs0 # by combining an initial DOA angle estimation formula, and calculating an estimated direction of arrival of each narrowband far-field information source incident to the expanded co-prime array to obtain K estimated directions of arrival theta'k. As a receiving signal vector x (t) obtained by expanding a co-prime array cannot be directly applied to the Root MUSIC algorithm, the efficient DOA estimation algorithm disclosed by the invention can be directly applied to the Root MUSIC algorithm by constructing a selection matrix G to calculate and obtain a (theta k).

The application discloses a V-shaped coprime array two-dimensional direction finding method and system based on array transformation, which first improves the array on the basis of a traditional shape coprime array. Secondly, the array antenna of the array improved shape sparse array structure receives signals, and through solving a covariance matrix and eigenvalue decomposition, a noise subspace is obtained. Finally, a MUSIC spectrum function is constructed, joint elevation and azimuth are searched and obtained based on the noise subspace, and finally, the DOA estimation value of the signal source is calculated. The array structure VCACS and VCACSS proposed in the application have greater degrees of freedom and fewer array elements for two-dimensional parameter estimation, so that the azimuth and the elevation are not affected when the azimuth and the elevation are estimated respectively, and the estimation result is more accurate.

This invention discloses a design method for a Type I ternary coprime array based on coprime sparse arrangement, relating to the field of array structure design. Two coprime positive integers M and N are selected to construct the basic structure of a prototype coprime array. A subarray with n elements and n spacing is added in reverse to the prototype coprime array to form a Type I ternary coprime array. Based on the distribution law of holes in the prototype coprime array, the lower bound expression of the optimal parameters of the subarray can be obtained, ensuring that the holes in the prototype coprime array are completely filled. Analytical expressions for the distinct and continuous degrees of freedom of the Type I ternary coprime array are derived. The method is scalable, allowing for the expansion of array degrees of freedom without destroying the prototype coprime array structure by adding array elements in reverse. The Type I ternary coprime array designed using this method exhibits weak mutual coupling, scalability, and high distinct degrees of freedom.

The invention belongs to the technical field of information and marine science and technology, and discloses a UUV broadside array DOA estimation method based on conjugate enhancement and virtual extension. According to the method, conjugate enhancement processing is carried out on parallel co-prime array receiving signals, augmented statistical matrixes including autocorrelation, conjugate autocorrelation, cross-correlation and conjugate cross-correlation are calculated, and weighted combination is carried out to construct an extended correlation matrix. The method comprises the following steps: constructing a virtual uniform linear array by using the differential common-array characteristic of a co-prime array, designing a redundancy integration matrix to perform redundancy elimination processing on a covariance matrix, obtaining an equivalent signal of a virtual array, and further reconstructing a virtual array covariance matrix with a Toeplitz structure, and finally, high-precision and automatic pairing estimation of the azimuth angle and the pitch angle of the underwater target is realized through a dual-rotation invariant subspace algorithm. According to the method, the array aperture is expanded, the estimation robustness in a low signal-to-noise ratio environment is improved, spectral peak search is not needed, and technical support is provided for UUV underwater target positioning.

This invention discloses a coherent source adaptive beamforming method based on coprime array interpolation, belonging to the field of radar anti-jamming technology. It comprises two stages: a first stage of decoherence covariance matrix reconstruction and a second stage of adaptive beamformer construction. In the first stage, by constructing a sensor position model of the coprime array, a mathematical model of signal reception, descriptions of signal and interference, and the definition of the steering vector, the received signal is interpolated. The method utilizes the properties of decoherence by taking a diagonal matrix and the Vandermonde decomposition of the Taplez matrix to achieve effective separation of coherent source interference from the target signal. In the second stage, by reconstructing the interference and noise covariance matrices, an adaptive beamformer is designed, ultimately achieving high-precision detection and extraction of target signals in complex environments.

The invention is suitable for the technical field of array signal processing, and provides a frequency diversity co-prime array angle and distance estimation method, which comprises the following steps: designing a supervised hole completion network to establish a mapping model from a hole-containing virtual signal to a complete virtual array signal, and the calculation complexity in the subsequent space smoothing process is reduced by designing a matrix reconstruction method, and finally, a target sensing result is output by combining a MUSIC algorithm. The frequency diversity co-prime array receives signals as input, angle and distance information of each target can be output after iterative training, and estimation accuracy and robustness are improved.

The invention provides a k-fold expansion and filling co-prime array design method. The k-fold expansion and filling co-prime array design method comprises the following steps of 1, setting a structure of an original co-prime array; 2, constructing an expanded co-prime array, and determining the positions of holes in a non-negative part in a differential co-array; 3, constructing a k-fold expanded co-prime array, and determining the value of the sub-array spacing and the position of a non-negative part hole in a differential co-array; 4, through hole filling, constructing a k-fold expansion filling co-prime array, and calculating a physical aperture, a uniform degree of freedom, a degree of freedom, a weighting function and optimal configuration of parameters when the uniform degree of freedom is given; and step 5, filling part of array element spacing of the co-prime array by compressing k-fold expansion, constructing a k-fold expansion filling co-prime array with compressed array element spacing, and determining composition conditions of the array. According to the method, the differential common-array freedom degree is remarkably improved, the mutual coupling effect between array elements is effectively restrained, and therefore the DOA estimation precision and the resolving power are improved.

This application provides a near-field target localization method, apparatus, electronic device, and storage medium, belonging to the field of communication technology. The method includes: acquiring an initial received signal of a preset symmetric coprime array; determining a first covariance matrix of the initial received signal based on the initial received signal; performing calculations based on the first covariance matrix to obtain an equivalent received signal of the initial received signal; determining a second covariance matrix of the equivalent received signal based on the equivalent received signal; performing spatial smoothing on the second covariance matrix to obtain a third covariance matrix of the equivalent received signal; performing a one-dimensional angle spectral peak search on the third covariance matrix to obtain a first angle between the near-field target and the central array element; and performing a one-dimensional distance spectral peak search on the first covariance matrix based on the first angle to obtain a first distance between the near-field target and the central array element. This application significantly reduces the computational overhead during near-field target localization.

The present invention discloses a coherent signal DOA estimation method based on a coprime array. First, the covariance matrix of the coprime array is calculated, and eigendecomposition is performed on it to find the eigenvector corresponding to the maximum eigenvalue. The eigenvector is then decomposed into two parts according to the number of array elements of the coprime array, and the elements of the two parts are rearranged to obtain two Hankel matrices H1 and H2. Next, singular value decomposition is performed on H1 and H2 to obtain the noise subspaces of H1 and H2. Finally, based on the noise subspaces of H1 and H2, the spatial spectra of H1 and H2 are plotted using the MUSIC method. The same spectral peaks in the spatial spectra of H1 and H2 are found, and the DOA values ​​corresponding to the spectral peaks in the spatial spectra of H1 and H2 are recorded and averaged to obtain the final DOA estimate. The method of the present invention does not require vectorization of the received signal of the sparse array, can fully utilize the coprime characteristics of the array, and obtain the angle estimate of the coherent signal, thus filling the gap in coherent signal arrival angle estimation for coprime arrays.

A method and a device for constructing a redundancy-removed coprime radar array based on one-bit quantization. The method includes obtaining a first sub-array element and a second sub-array element both used for constructing a redundancy-removed coprime radar array, and determining a redundancy-removed coprime array respectively corresponding to the first sub-array element and the second sub-array element by a graph theory method; obtaining target echo data of the redundancy-removed coprime array, and obtaining a target radar array by performing one-bit quantization on the target echo data for completing array cavities of the redundancy-removed coprime array; moreover, before the completing, positions of all non-empty array elements in a redundancy coprime array are used to place radars, and before the completing, the radars are not arranged in positions of empty array elements.

The invention discloses an II-type ternary co-prime array design method based on co-prime sparse arrangement, and relates to the field of array structure design. Basic co-prime number pairs, additional array elements and third sub-array parameters are determined, two co-prime positive integers M and N are selected to construct a prototype co-prime array basic structure, a prototype co-prime array comprises a sub-array 1 with the array element number being N and the interval being Md and a sub-array 2 with the array element number being M and the interval being Nd, and d is the unit array element interval; an array element is added in the positive direction of the prototype co-prime array, and then uniform sub-arrays with the number of the array elements and the interval of the array elements are added in the reverse direction, so that the II-type ternary co-prime array is formed. The II-type ternary co-prime array designed by the method has the characteristics of high continuous degree of freedom, weak mutual coupling, modularization and expandability.

The invention discloses an I-type ternary co-prime array design method based on co-prime sparse arrangement, and relates to the field of array structure design. Selecting two co-prime positive integers M and N to construct a prototype co-prime array basic structure; a group of sub-arrays with the array element number being 1 and the interval being 1 are reversely added on the basis of the prototype co-prime array, and an I-type ternary co-prime array is formed; on the basis of a prototype co-prime array hole distribution rule, an optimal parameter lower bound expression of the sub-array can be obtained, so that prototype co-prime array holes are completely filled; deriving analytic expressions of dissimilar degrees of freedom and continuous degrees of freedom of the I-type ternary co-prime array; and expandability is achieved, the prototype co-prime array structure is not damaged, and array freedom degree expansion is achieved by reversely increasing array elements. The I-type ternary co-prime array designed by the method has the characteristics of weak mutual coupling, expandability and high dissimilar degree of freedom.

The invention provides a convolution beam space DOA estimation method based on hole filling, so as to solve challenges faced by a traditional convolution beam space method. According to the algorithm, differential common array holes are filled through low-rank matrix recovery, a solving framework is constructed through an alternating direction multiplier method, and a multi-phase component averaging strategy based on a sliding window is designed for the extraction process. Simulation results show that the method solves the problem that the precision of a traditional convolution beam space method is reduced, and only negligible extra time overhead is introduced. Through comparison, the performance of the provided method is better than that of a traditional convolution beam space method and a method based on atom norm minimization and CVX toolbox solving, and the advantages are crucial for realizing real-time and high-precision DOA estimation in a large-scale extended co-prime array scene.

The invention provides a sparse array uplink beam forming method for a dual-function communication radar system, and the method comprises the following steps: 1, constructing a sparse array: employing a co-prime array, a nested array and an enhanced nested array, and expanding the aperture through a difference set virtual array and a sum set virtual array; 2, generating virtual array data: constructing measurement data through covariance matrix vectorization and pseudo covariance matrix vectorization; step 3, scene adaptive beam forming: for different angles, distributing a radar target and a communication user to different beams through a convex optimization tool; for the same angle, spatial diversity constraint and orthogonality constraint are introduced, an independent beam former is designed, and cross interference is suppressed. Fusion of aircraft communication and radar detection functions is supported, and target detection and information interaction efficiency in space tasks is improved.