A photonic implementation of a wide-band nulling system for phased arrays

This letter presents a novel architecture for independently steering broad-band nulls for phased array antennas. Measurements taken over a ten percent fractional bandwidth on a three-element proof-of-concept system shows a null depth of better than 40-dB uniform across the entire band in this laboratory setup. The architecture presented is best suited for small antenna array applications, for example self-guided airborne munitions. In a fully integrated, optimized system, null depths of 50-70 dB or greater across a multigigahertz bandwidth are anticipated and the critical factors, which influence this performance, are examined.