Angle Estimation of Distributed Source for Monostatic MIMO Radar in Colored Noise

An angle estimation algorithm based on fourth-order cumulants for distributed targets in monostatic Multiple Input Multiple Output (MIMO) radar is proposed in this paper, which could be used to deal with the problem of the performance declining in colored noise based on second order statics algorithm. At first, the signal model of coherent distributed targets is constructed, and then the fourth-order cumulants matrix can be calculated. Based on the eigen-decomposition, the signal subspace and the noise subspace, which are orthogonal, can be derived. Finally, according to the principle of the MUltiple SIgnal Classification (MUSIC), the spectral function can be obtained, and with spectral peak searching, the central direction of arrival is estimated. The proposed algorithm makes full use of the property of fourth-order cumulants which ignores the Gaussian process to restrain the influence of the colored noise on estimating the angles. The computer simulation results demonstrate the correction and efficiency of the proposed method.