Pattern Control for Reflector Antennas Using Electronically-Reconfigurable Rim Scattering

In prior work, we demonstrated sidelobe nulling for a reflector antenna system by electronic modification of the phase of scattering from elements located near the rim of the reflector. Applications for such a system include radio astronomy, where deleterious levels of interference from satellites enter through sidelobes. However the prior work was limited to placing single nulls with no constraint on main lobe characteristics, leading to gain which varies as a function of null direction. In this work, we consider simulated annealing as a means of placing nulls simultaneously with enforcement of a gain constraint. Using this method, deep nulls are possible even when element control is limited to discrete binary (i.e., 1-bit) phase-only control.