Design and Synthesis of Patch Microwave Couplers

Abstract

This paper describes a simple design and synthesis technique that allows an alternative to the standard quadrature hybrid coupler to be constructed. The alternative coupler consists of a rectangular patch of microstrip material whose dimensions have been selected in order to achieve a specified power coupling factor between output ports at a given frequency. Experimental and theoretical results are presented for the behaviour of these couplers as a function of frequency.