REALIZATION OF MINIATURIZED QUADRATURE HYBRID COUPLER WITH REDUCED LENGTH BRANCH ARMS USING RECURSIVELY LOADED STUBS

This paper presents a novel design of miniaturized microstrip quadrature coupler at 2.45GHz. The design topology is based on reduced transmission line branch arms using recursively loaded stubs that contribute to the compact size. The proposed coupler result in a size reduction of 70.4% when compared to a conventional branch line hybrid. The designed coupler provides, at the operating frequency, a 25dB isolation and exhibits equal power division at the output ports with quadrature phase difierence. A fabricated prototype is developed with simulation and measurement in close agreement.