Nested array non-circular signal DOA estimation method based on BNC in impulse noise environment

Abstract

The invention discloses a nested array non-circular signal DOA estimation method based on a BNC in an impulse noise environment, and the method comprises the steps: receiving a signal through an array antenna of a nested array structure, and obtaining received signal information x (t); expanded signal information X (t) is constructed according to the non-circular characteristics of the signals, and a BNC matrix RBNC of the expanded signal information X (t) is calculated; carrying out vectorization and rearrangement processing on the RBNC to obtain a virtual array receiving signal z; and removing redundancy of a virtual array receiving signal z to obtain a new virtual uniform linear array receiving signal pair, respectively performing spatial smoothing and splicing on a mid-difference array and a continuous part of the array with the array element spacing of half wavelength to obtain virtual array information Y, constructing a covariance matrix RY for the Y, and obtaining accurate estimation of the DOA by using a dimension reduction MUSIC method. According to the method, a bounded nonlinear function is used for suppressing abnormal values in received signals, a BNC matrix is constructed, vectorization processing, rearrangement and redundancy removal are carried out to obtain virtual uniform linear array received signal information with the array element spacing being half-wavelength, and a dimension reduction MUSIC method is adopted, so that the calculation complexity is reduced.

Description

technical field [0001] The invention belongs to the field of direction of arrival (direction of arrival, DOA) estimation, in particular to a DOA estimation method for nested array non-circular signals based on bounded nonlinear covariance (Boundednonlinear covariance, BNC) in an impulse noise environment. Background technique [0002] In recent years, a new type of sparse array has received much attention, the nested array, which is composed of two uniform linear arrays. N 1 +N 2 A nested array of array elements can obtain 2N 2 (N 1 +1)-1 virtual linear array continuous degree of freedom (degreeoffreedom, DOF), and uniform linear array (uniform linear array, ULA) with the same number of array elements can only obtain N 1 +N 2 DOF of -1. Therefore, the nested array structure greatly increases the number of detectable sources and can improve the performance of angle estimation. [0003] Furthermore, most DOA estimation methods in sparse arrays assume a Gaussian distribu...

AI Technical Summary

Problems solved by technology

[0003] Furthermore, most DOA estimation methods in sparse arrays assume a Gaussian distribution of ambient noise

However, the noise in practice often shows non-Gaussian characteristics, and will show certain impulse noise characteristics

In high impulsive noise environments, the second moment of the received signal no longer exists, and the performance of these DOA estimation methods will drop significantly

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