Efficient analysis of arrays of rectangular corrugated horns: the synthetic aperture function approach

This paper presents a procedure to reduce the computational effort for the full-wave analysis of corrugated or stepped rectangular horns/cavities, open-ended on an infinite ground plane. This procedure, framed in the method of moments (MoM), is based on the construction of appropriate basis functions generated by solving the problem of one element in isolation. These functions are termed "synthetic aperture functions" (SAF); being numerical solutions of a physical problem, they have the adequate contents of high-order waveguide modes which allow the proper storage of local reactive energy. They also include a good approximation of the correct edge behavior. The technique reveals a significant reduction of computational resources compared to an ordinary MoM solution, especially for a large number of radiating elements