Analysis of the Accuracy of Estimating the Angle of Arrival of a Signal in an Inhomogeneous Sparse Antenna Array

In this paper, the characteristics analysis of a set of inhomogeneous sparse antenna arrays is carried out. The considered set of the sparse arrays is obtained by moving the antenna elements of a uniform equidistant linear array from the middle to the edges of the antenna in order to increase the accuracy of the angle-of-arrival (AoA) estimates. The theoretical analysis of the accuracies of the AoA estimates is carried out by finding the Cramer-Rao lower bounds (CRLB). The signal processing algorithm for finding the maximum likelihood (ML) estimates were implemented. For the considered set of the inhomogeneous sparse antenna arrays the careful simulations of the developed signal processing algorithm were performed. Threshold values of SNRs were obtained. It was shown that for SNRs exceed these threshold values the of the obtained estimates accuracy of the AoA practically coincides with the theoretical limits.