Synthesis of radiation patterns of planar array antennas

Abstract

In the course of developing a point design for a bootlace lens antenna for a space-based radar, a versatile radiation-pattern synthesis technique capable of simultaneously controlling the mainlobe shape and the sidelobe level has been developed for planar phased arrays. Utilizing certain minimax properties of a power functional, the method does not rely on the shape of special mathematical functions and is therefore applicable to a broader class of arrays. After a brief description of its principle, which is based on the extension of an earlier procedure developed for linear arrays by the same author, the technique is applied to the synthesis of the radiation pattern of the feed array of the space-fed lens antenna. The objective is to obtain as closely as possible a two-dimensional Gaussian illumination function on the lens surface, while at the same time maintaining a low sidelobe level to minimize the feed loss due to spillover. Results of this synthesis are presented and discussed. >