Bandwidth improvement of a rear end slot antenna on a Substrate Integrated Waveguide cavity

Abstract

A technique for enhancing the bandwidth of the planar slot antenna on the substrate integrated waveguide cavity has been discussed in this paper. Planar slot antennas are extensively used in research because of its simple profile and moderate gian. Inspite of employing a planar rectangular slot which results in a narrow bandwidth, a broadband slot can be used to improve the bandwidth. This slot antenna is been placed at the rear end of the substrate integrated waveguide and excited by 50Ω grounded coplanar waveguide to provide good isolation. The substrate integrated waveguide adopts the mm wave technology and it facilitates the feeding element and the antenna to be built on the same substrate. The return loss is obtained as -30 dB and -22 dB at 10GHz and impedance bandwidth of 1.98% and 9.9 % for the rectangular slot and the broadband slot respectively. Further the performance is analysed by varying the height of the substrate, the length and width of the slot. The benefits of the antenna include simple profile, low weight, easy fabrication and integration with planar circuits.