Array geometry impact on music in the presence of spatially distributed sources

Abstract

The MUltiple SIgnal Classification (MUSIC) estimator has been widely studied for a long time for its high resolution capability in the domain of the direction of arrival (DOA) estimation, with the sources assumed to be point. However, when the actual sources are spatially distributed with angular dispersion, the performance of the conventional MUSIC is degraded. In this paper, the impact of the array geometry on the DOA estimation of spatially distributed sources impinging on a sensor array is considered. Taking into account a coherently distributed source model, we establish closed-form expressions of the MUSIC-based DOA estimation error as a function of the positions of the array sensors in the presence of model errors due to the angular dispersion of the signal sources. The impact of the array geometry is studied and particular array designs are proposed to make DOA estimation more robust to source dispersion. The analytical results are validated by numerical simulations.

DOA Estimation of Two-Dimensional Coherently Distributed Sources Based on Spatial Smoothing of Uniform Rectangular Arrays

“…From equations (10)- (12) we can conclude that the received vector of (m, k)th subarray along x axis can be obtained as…”

“…According to equations (10)- (12), the received vector of closest mth and parallel to z axis array z 11 m can be expressed as…”

“…Supposing that signals from different CD sources are coherent, sample covariance matrices are rank deficient. us, subspace-based algorithms [1,2,[12][13][14][15][16][17][18][19] and ESPRIT class algorithms [20][21][22][23] which are based on eigendecomposition of sample covariance matrices cannot be applied for DOA estimation. PM class algorithms [24][25][26][27] based on linear operation of full rank sample covariance matrices are no longer applicable too.…”

“…In [1,[6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23], CD sources have been regarded as uncorrelated with each other; estimators cannot be applied for CD sources which are correlated. In [24], CD sources correlated with each other are discussed while sources are supposed to be 1D case.…”

Direct Position Determination of Coherently Distributed Sources based on Compressed Sensing with a Moving Nested Array

“…In these circumstances, the radio signal sources have a certain angle spread, which is equivalent to the distributed source model. According to the different spatial distribution characteristics of the sources, the distributed source models are divided into the coherently distributed source (CD) models [9,10] and the incoherently distributed (ID) source models [11,12]. This paper mainly concentrates onthe DPD technology of the coherently distributed sources.…”