Continuous Beam Steering For Phaseless Direction-of-Arrival Estimations

This letter presents a system capable of continuous beam steering for direction-of-arrival (DoA) estimation operating at 2.45 GHz, based on the use of a digitally controlled beamforming network and exploiting a bimodal circularly polarized patch antenna. The network is composed by a digitally controlled attenuator, a phase shifter, and a Wilkinson power divider. The specific achieved beam set constitutes the key feature that allows the DoA estimation approach, based on the phaseless magnitude data of the received signals. Experimental validation confirms a DoA estimation error as low as 0.7° within the range from -90° to +90°, with a standard deviation of 0.6°.