volume | PIER Journals

Abstract

This paper presents a novel design of miniaturized microstrip quadrature coupler at 2.45 GHz. 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 25 dB isolation and exhibits equal power division at the output ports with quadrature phase difference. A fabricated prototype is developed with simulation and measurement in close agreement.

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12. , , Users Manual, CST Microwave studio 2010.

Prof. Rowdra Ghatak

Dr. Manimala Pal

Mr. Biswajit Sarkar