45 results about "Coprime array" patented technology

The invention discloses a co-prime array DOA (direction of arrival) estimation method based on interpolation virtual array covariance matrix Toeplitz reconstruction, and mainly solves a problem of information loss caused by the heterogeneity in a virtual array in the prior art. The method comprises the implementation steps: constructing a co-prime array at a receiving end; receiving an incident signal through the co-prime array, and carrying out the modeling; calculating an equivalent virtual signal corresponding to the signal received by the co-prime array; constructing an interpolation virtual array and carrying out the modeling; constructing a multi-sampling snapshot signals of the interpolation virtual array and a sampling covariance matrix; constructing a projection matrix, and defining projection calculation related with the projection matrix; constructing a reference covariance matrix according to all information in an original virtual array, designing an optimization problem based on the interpolation virtual array covariance matrix Toeplitz reconstruction, and solving the optimization problem; and carrying out the DOA estimation according to the reconstructed interpolation virtual array covariance matrix. The method improves the freedom degree and resolution of signal DOA estimation, and can be used for the passive positioning and target detection.

The invention discloses a direction of arrival estimation method based on covariance matrix reconstruction of an interpolated coprime array, which mainly solves the problem of information loss existing in the prior art based on virtual domain statistical signal processing. The implementation steps are: constructing a coprime array at the receiving end; using the coprime array to receive the incident signal and modeling; transforming the coprime array into a uniform linear array according to the idea of ​​interpolation, and constructing the corresponding received signal model; calculating the interpolation Sampling covariance matrix of coprime array; construct projection matrix corresponding to sampling covariance matrix of interpolation coprime array; design convex optimization problem based on kernel norm minimization to realize Toeplitz reconstruction of covariance matrix of interpolation coprime array ; Perform DOA estimation based on the reconstructed interpolated coprime array covariance matrix. The invention improves the degree of freedom and the accuracy of the estimation of the direction of arrival of the signal, and can be used for passive positioning and target detection.

The invention belongs to the array signal processing technical field and relates to a co-prime area array-based two-dimensional direction of arrival quick estimation method. The co-prime area array-based two-dimensional direction of arrival quick estimation method includes the following steps that: of: array manifold matrixes are constructed on the basis of an x-axis and a y-axis respectively according to a co-prime area array model, two uniform sparse area arrays are combined so as to form the co-prime area array model; the covariance matrixes of the received signals of the sub-arrays are solved, the propagation operator matrixes of the arrays are constructed on the basis of the x-axis and the y-axis; a PM (Propagator Method) is adopted to solve the twiddle factor matrixes of the sub-arrays along the x-axis and y-axis on the basis of block processing performed on the array manifolds; and angle ambiguity is eliminated through using the co-prime theory of planar arrays, and the azimuthsand pitch angles of the arrays are solved. With the method of the invention adopted, low-complexity, high-precision and fuzzy-free joint estimation of the pitch angles and azimuth angles under the co-prime area array model can be realized.

The invention discloses a direction of arrival estimation method based on relatively prime array second-order equivalent virtual signal disperse Fourier inversion. The objective of the invention is tosolve problems of high calculation complexity and a failure of simultaneously estimating signals and power in the current method. The method comprises following achieving steps that a receiving end builds a relatively prime array; by use of the relatively prime array, emission signals are received and modeling is performed; according to the received signals of the relatively prime array, deviating second-order equivalent virtual signals corresponding to augmentation virtual uniform linear arrays; defining angle-space frequency and using the angle-space frequency to describe second-order equivalent virtual signals of the virtual uniform arrays; carrying out disperse Fourier inversion on the second-order virtual signals described by use of the angle-space frequency, and constructing a space-power spectrum; and according to the constructed space-power spectrum, carrying out spectrum peak searching so as to acquire direction of arrival estimation and power estimation information the signals. According to the invention, the degree of freedom of estimation of the direction of arrival is improved; calculation complexity of the direction of arrival is reduced; and power estimation information of the signals can be acquired.

The invention discloses a coprime array underdetermined direction finding method based on the atomic norm. In the invention, the antenna of the receiving end is structured according to the coprime array; modeling is performed according to the received signal of the array; the output signal of the virtual array is calculated; and the interpolation is initialized Output signal; design an optimization method based on atomic norm to restore the interpolated output signal; reconstruct the covariance matrix of the interpolated virtual uniform linear array signal; estimate the direction of arrival based on the reconstructed covariance matrix. The present invention interpolates the discontinuous virtual linear array of the coprime array to the virtual homogeneous array through interpolation, which makes full use of the degrees of freedom and array element information of the coprime array; when vectorizing the covariance matrix to obtain the output signal of the virtual array, The signals at the same position are averaged, so that the information of the signal can be fully utilized than directly selecting the first signal at the same position; the base mismatch problem of the traditional sparse representation method can be avoided, and denoising is introduced when optimizing the problem operation, improving the accuracy of direction finding.

A dual-hole coprime array antenna structure is composed of four sparse subarrays, the total number of array elements is T, and the number of antennas are N and M respectively, wherein N and M are coprime integers, and M<N. The position of the array elements in the CATHDC antenna structure is where d≤λ / 2 is the unit array element spacing, and λ is the carrier wavelength. The antenna structure of the present invention expands the antenna aperture and weakens the mutual coupling effect. The antenna array layout is simple and can Gain more degrees of freedom than existing coprime arrays. The virtual array generated by CATHDC is a uniform array with unit element spacing, and the classical signal angle of arrival estimation algorithm combined with the spatial smoothing method can be directly applied without angle ambiguity.

The invention discloses a wideband signal DOA estimation method based on a coprime array, comprising: S1, designing a coprime array structure by using an antenna; S2, sampling and discrete Fourier transforming the wideband signal received by the antenna in the coprime array Transform to obtain the frequency domain signal output model; S3, calculate the autocorrelation matrix of the frequency domain signal output model and vectorize it to obtain a new signal model; S4, process the new signal model to obtain the spatial smoothing coherence of the wideband signal Variance matrix; S5, dividing the airspace network, constructing a dictionary, and using the dictionary at multiple frequency points of the broadband signal to perform sparse representation of the spatial smooth covariance matrix, forming a multi-measurement vector sparse representation model of multiple dictionaries of the broadband signal ; S6, realize the DOA estimation of broadband signals in the form of solving the sparse inverse problem through the joint sparse constraints on the multi-dictionary sparse representation coefficients. The invention can improve the estimation accuracy of the direction angle of the broadband signal under the low signal-to-noise ratio, and reduce the direction-finding error.

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.