Aperture Phase GA Optimization for Reflectarray Antennas with Feed Lateral Displacement

In this paper, an aperture phase optimization method using genetic algorithm (GA) for a reflectarray (RA) with a horizontal moving feed is presented. To improve the beam-scanning performance of the RA, the gain and BWFN (beam width between first nulls) of uv planar are introduced as key indicators in the phase optimization to reduce the gain variation. A full-wave simulation has been carried out to verify the method, and the results show that the gain variation of the optimized RA is smaller than 2 dB within ±30° scan coverage, while it is 4.6 dB for the traditional narabolic design.