Angle-of-Arrival Estimation Using Different Phase Shifts Across Subarrays in Localized Hybrid Arrays

Angle-of-arrival (AoA) estimation, even for a single arriving signal, in a localized hybrid array is challenging and time-consuming due to a phase ambiguity problem. Subarrays use the same phase shifting values conventionally to exploit cross correlation between them. This results in the requirement of scanning multiple angles over excessively long periods to resolve the phase ambiguity problem. In this letter, we propose an approach which allows subarrays to use different phase shifts per estimation and can resolve the ambiguity problem by directly estimating the desired AoA parameter. This can potentially speed up the estimation and improve the estimation performance significantly. Simulation results are provided to demonstrate the effectiveness of the proposed approach.