Research On Array Signal Processing Technology With Small Snapshot Numbe

Array signal processing is to use a sensor array arranged in a certain way in space to receive spatial signals,and extract useful parameter estimation according to the relationship between the array and the signal related features.This paper mainly focuses on the in-depth study of the direction of arrival(DOA)estimation and beamforming technology in array signal processing under the small snapshot number scenario.There are mainly three parts as follows:(1)Aiming at the problem that the DOA estimation accuracy of narrowband signals decreases under small number of snapshots,this paper proposes a DOA estimation based on the Black Widow Optimization Algorithm to optimize the depth expansion network.First of all,the traditional fixed point continuity(FPC)algorithm is improved.Norms are used instead of norms.At the same time,adaptive outlier tracking(AOP)algorithm is used to deal with symbol reversal caused by noise.Then based on the improved fixed point continuous algorithm,build a deep expansion network for DOA estimation.At the same time,the black widow algorithm is used to optimize the neural network parameters,improve the estimation performance and accelerate the convergence speed.Experimental results show that the proposed algorithm has better direction finding performance in small snapshots and high signal-to-noise ratio scenes.(2)For wideband signal DOA estimation,this paper proposes a wideband DOA estimation algorithm based on principal component analysis and feedforward neural network.Firstly,an optimal focus matrix construction criterion is proposed,and then the signal subspace is estimated using principal component analysis method and single-layer feedforward neural network.The complexity of the proposed algorithm is low,and its performance is very close to that of existing broadband DOA estimation algorithms,and the estimation performance is good under small snapshots.(3)In order to solve the problem of poor performance of traditional adaptive beamforming method under small snapshots and high signal-to-noise ratio,this paper proposes a beamforming algorithm based on Aquila Optimizer(AO)optimized diagonal loading technology.Firstly,the unit matrix and sample covariance matrix are linearly combined to obtain a better covariance matrix,and then the Aquila optimizer is applied to the diagonal loading technology to find the optimal diagonal loading value.Experiments show that the algorithm has good stability.