Moment method analysis and genetic algorithm design of shaped beam pillbox antennas

This paper describes a design methodology for designing shaped beam pillbox antennas using a spectrum of two-dimensional solutions (S2DS) and genetic algorithms. The pillbox antenna is a type of parallel plate waveguide antenna that can be thought of as a cylindrical reflector and feed system confined between two parallel plates. The pillbox antenna can in many respects be analyzed as a two-dimensional structure, or be divided in two two-dimensional problems, as we outline here: one for the parallel plate reflector system and one for the outer two-dimensional horn. The full three-dimensional pattern is obtained by pattern multiplication with a very high degree of accuracy in the region of interest. Likewise, the total gain is efficiently calculated as the product of the elevation gain and the azimuth gain.