Designing microstrip transitions into parallel-plate regions using the FDTD method

Abstract

A design method is introduced for microstrip transitions between microstrip lines and parallel plate regions. The radiation impedance of an aperture radiating into a two-dimensional region (i.e., parallel-plate region) is obtained by the FDTD method, and then a multisection matched transition is designed between this aperture and a microstrip line. Numerical study of a sample design has shown that the 20 dB return loss bandwidth is about 40% for a two-section transition. (C) 1999 John Wiley & Sons, Inc.