A new high-resolution-and-capacity DOA estimation technique based on subarray beamforming

A new direction-of-arrival estimation technique using subarray beamforming is proposed. Two virtual subarrays are used to form a signal whose phase relative to the reference signal is a function of the direction of arrival. The direction of arrival is then estimated based on the computation of the phase shift between the reference signal and its phase-shifted version. Since the phase-shifted reference signal is obtained after interference rejection through beamforming, the effect of cochannel interference on the estimation is significantly reduced. The proposed technique is computationally simple and the number of signal sources detectable is not bounded by the number of antenna elements used. Simulation results show that the proposed technique leads to higher estimation resolution and capacity than existing techniques.