A novel broadband high power coaxial-to-CPW directional coupler

A new class of broadband Coaxial-to-CPW (Copla-nar Waveguide) directional couplers for high power applications is studied. The new coupler overcomes the drawbacks of mi-crostrip, stripline, and coaxial couplers and allows simple and low cost mechanical construction. In this paper we present the design, simulation and implementation of a broadband (3GHz to 11GHz) directional coupler with directivity of more than 20dB over the whole band. Simulation results using the HFSS software demonstrate good agreement with experimental results.