Design of Ridged Structural Composite Transmission Line

Abstract

In this paper, a structural composite transmission line composed of the ridged substrate integrated waveguide (RSIW) and the embedded ground coplanar waveguide (GCPW) is proposed for parallel transmission of multi-mode signals. The structure makes full use of the waveguide space to efficiently excite the TE20 mode of the RSIW and the quasi- TEM mode of the GCPW without increasing the number of substrate layers. Simulation results show that the insertion loss $\vert S_{21}\vert$ of the RSIW is less than 1.3dB, and $\vert S_{43}\vert$ of the GCPW is less than O.5dB within their respective working bandwidth. The isolation $\vert S_{31}\vert$ between the two waveguides is greater than 55dB. The proposed structural composite transmission line would be attractive for future multi-frequency and multi-function system.