A Low-Complex One-Snapshot DOA Estimation Algorithm with Massive ULA

The conventional direction of arrival (DOA) estimation algorithms, e.g., MUSIC, root-MUSIC, and ESPRIT, may not be effective when applying to massive antenna array configuration, because they not only require a large amount of receive snapshots but also suffer from forbiddingly high computational complexity. In this letter, we propose a low-complex DOA estimation algorithm for massive uniform linear array. We first obtain coarse initial DOA estimates via the fast Fourier transmission and then search for the accurate estimates within a very small region. The proposed method needs one snapshot only and could achieve very high accuracy that is close to the Cramer-Rao bound. Simulation results are provided to corroborate the proposed studies.