Propagation characteristic of ridge substrate integrated waveguide

Abstract

In this paper, a compact and broadband ridge substrate integrated waveguide (RSIW) is analyzed, which is low-loss and easy to fabricate. The RSIW is based on substrate integrated waveguide (SIW), and can be completed by inserting a longitudinal central partial-height cuboid metal block or etching a longitudinal central partial-height cuboid then coating the outer surface with metal. Analytical relationship between cutoff frequency and ridge width, relative bandwidth and ridge height is systematically studied. According to the analytical formulas, an X band frequency multiplication RSIW is designed. The simulation results indicates that the insertion loss is lower than 0.043dB, the return loss is higher than 29.9dB, and the cutoff frequency of TE10 mode and TE20 mode respectively are 5.125 GHz and 15.375 GHz, which are in good agreement with the formulas.