Planar waveguide model of Rotman lens

Abstract

A boundary integral equation method for the analysis of stripline and microstrip lenses is presented. The field distributions across the port apertures surrounding the lens's cavity are described by a contour integral that satisfies the wave equation in the planar lens cavity. All mutual couplings and hence internal reflections between ports are taken into account. The model is used to predict the performance of a nonoptimal Rotman lens with 8 input ports and 20 output ports. There is a good agreement with the measured results for both port coupling and match.<>