Simple analysis and design of a new leaky-wave directional coupler in hybrid dielectric-waveguide printed-circuit technology

This paper presents a new theory to analyze and design a novel leaky-wave coupler based on a hybrid dielectric-wave-guide printed-circuit technology. The analysis theory is based on a combined method of moments (MoM) geometrical optics (GO) technique, which makes use of the leaky mode complex propagation constant. This MoM-GO approach allows to easily obtain the response of the coupler, and to illustratively understand the working mechanism of the proposed structure. A coupler is designed to work at 5.5 GHz. Leaky mode results are compared with three-dimensional finite-element method simulations, showing the validity and accuracy of the new theory developed. This novel directional coupler presents interesting advantages when compared to previous wave couplers. © 2006 IEEE.