Substrate integrated waveguide slot antenna with shorting vias for broadband applications

Abstract

A substrate integrated waveguide cavity backed by a I shaped slot is presented in this paper. It is a simple profile and low cost antenna designed for broadband applications. The proposed antenna is analyzed with the absence and presence of shorting vias. The cavity without shorting vias exhibits three narrow resonances. By inserting shorting vias at appropriate positions around the slot, the current distribution varies such that bandwidth is extended. Further to reduce the size of the antenna, half mode substrate integrated waveguide is designed. The prototypes of two antennas are fabricated and their S parameters are measured. The via loaded cavity backed substrate integrated waveguide has bandwidth of 21% (10.2 to 12.6 GHz) and a peak gain of 6.05 dB whereas via loaded half mode substrate integrated waveguide has bandwidth of 23% (10 to 12.6 GHz) and a peak gain of 6.25 dB.