Input impedance of rectangular substrate integrated waveguide (SIW) cavity backed slot antennas

In this paper, modeling of the rectangular substrate integrated waveguide (SIW) cavity backed narrow slot antenna for input impedance is developed by using the transmission-line model and lumped-element circuit. The model of a transverse slot in broad wall of the waveguide is used in the transmission-line model. The results based on transmission-line and circuit modeling are presented and compared with those obtained by full wave simulation. The proposed model gives, for the first time, some fundamental characteristics of the rectangular SIW cavity backed narrow slot antenna.