Sensitivity of phase-based doa estimators to beamformer mismatch

Phase-based direction-of-arrival (DOA) techniques estimate the phase difference between the output signal of a conventional beamformer and that of a related parallel beamformer. Since the two beamformers share the same weights in a specific known manner, the DOA estimators are affected by any phase mismatch of the beamformer weights relative to the direction vector of the signal of interest. This paper investigates the sensitivity of two phase-based DOA estimators to such beamformer mismatch via a theoretical analysis, and presents an example computer simulation to illustrate their properties.