Experimental approach for determining the received pattern of a Rascan holographic radar antenna

Because of the nature of image formation for holographic radar, the role and relevance of antenna radiation pattern are different than for impulse radar, and thus have not been studied. We determine theoretical Rascan radiation patterns for different dielectric media, and compare simulations to experimental data from an antenna scanned across a spherical metal target at various ranges/depths. Positions at which the received signal (phase difference between object and reference beams) are the same within a single scan, and across scans at different depths provide a 3-D approximation of the effective radiation pattern that closely agrees with the simulations.