Characteristic planes of microstrip and unilateral finline tee-junctions

Abstract

A unique set of reference planes which enters into the description of a three port E or H-plane tee-junction are its characteristics planes. These planes correspond to the positions of a short circuit at one typical port that will decouple a second port from one input port. The purpose of this paper is to establish these planes in the cases of microstrip and unilateral finline circuits. This is done in each case for a number of different geometries. The spacing between the first two characteristic planes across the junction is 360 deg. In the case of the H-plane tee junction, it is 180 deg in the case of the E-plane geometry.