Joint frequency and DOA estimation using Fourier coefficient interpolation

A high accuracy and low complexity estimator for the unknown frequency and direction of arrival (DOA) of a sinusoid incident on a sensor array is proposed. The approach is to extend an existing Fourier coefficient interpolation scheme of Quinn, to a multi-sensor array. Simulation results show a mean square error in frequency of approximately 1.3 times the CRB, while for DOA it is approximately 1.1 times the CRB. As the method estimates frequency and DOA separately, there is a loss in threshold of 2dB for both frequency and DOA estimation compared to the method of joint maximum likelihood estimation.