Doubly Curved Reflector Design for Hybrid Array Fed Reflector Antennas

Abstract

This communication discusses a generalized analytical formulation for the design of doubly curved reflectors fed by line sources of any shape, including straight, circular, and even elliptical profiles. The proposed hybrid array fed reflector antenna configuration produces pencil beams from line sources which may be either passive multiple beam line sources or reconfigurable linear phased arrays. The proposed formulation, based on parabolic strips derived from geometrical optics considerations, reduces significantly phase aberrations which were responsible for beam squint and sidelobes imbalance with the previous simpler formulation. Numerical results are presented at Ka-band. This doubly curved reflector design is considered of interest in combination with linear phased arrays to introduce some level of coverage reconfigurability (one-axis beam steering) for on-board broadband satellite communication payloads with a much simpler focal array design when compared to existing planar phased array fed reflector antennas.