Direction-of-arrival estimation of broadband microwave signals in phased-array antennas using photonic techniques

A photonic technique for detecting the angle of arrival of broadband microwave signals in phased-array antennas is proposed. Using a photonic microwave filter and measuring the frequency of the notches created by the filter over the broadband signal, it is possible to derive its direction of arrival, even in the presence of several sources. The technique is intended to be used in optical-beamforming networks for phased array antennas. The architecture of the optical-beamforming network will be barely modified adding just a few additional components. Experiments showing the feasibility of the technique are provided.