EM design and analysis of a substrate integrated waveguide based on a frequency-selective surface for millimeter wave radar application

Substrate integrated waveguide (SIW) technology makes it possible to realize an entire circuit including a transition, planar circuitry, waveguide components and devices in a single printed circuit board. In this paper, a new approach to design a substrate integrated waveguide using a single square loop and Jerusalem cross frequency-selective surface elements as the top wall in place of a metallic wall, for advanced millimeter wave radar systems is presented. The guided wave and modes operating at the high-frequency range in V-band, typically 40–75 GHz (57–64 GHz in the USA and 59–66 GHz in Japan), has been analyzed. The accurate analytical modeling is used to calculate the complex propagation constant and cut-off frequency of the SIW structure. The propagation constant of the analyzed structured is compared with a conventional SIW, and the wave propagation is presented in all topologies. The leakage and attenuation loss of an electromagnetic wave due to different factors such as dielectric, conductor and radiation are also studied. Finally, the numerical simulation has been performed based on finite element and finite difference time domain to prove the analytical formulation of the proposed structure. The obtained simulation results are encouraging for developing a new type of SIW structure for aerospace applications.