ABSTRACT
In this paper, an efficient hybrid Direction of Arrival (DOA) estimation scheme based on the orthogonal projection criterion is devised for a massive uniform linear array. In this scheme, the DOA estimator, based on a Discrete Fourier Transform (DFT), is first applied to acquire coarse initial DOA estimates for a single data snapshot. Then, the fine DOA is accurately estimated through using the iterative search estimator within a very small region. It iteratively searches for the correct DOA vector by maximizing the objective function using a Taylor series approximation of the DOA vector with the one initially estimated. Since the proposed scheme does not need to perform eigendecomposition and a spectrum search while maintaining better DOA estimates, it also has low complexity and real-time capability. Simulation results are presented to demonstrate the efficiency of the proposed scheme.
