X-Band Circularly Polarized HMSIW U-Slot Antenna

Abstract

In this paper, a circularly polarized U-slot half-mode substrate integrated waveguide (HMSIW) antenna is proposed. It is based on a combination of U-shaped slot etched in the HMSIW top wall and a shorting via placed between the area bounded by the slot and the HMSIW bottom wall. The antenna is designed for the operating frequency of 10 GHz, parametrically studied, fabricated and experimentally verified. Experimental results proves that the fabricated prototype radiates a left handed circularly polarized (LHCP) electromagnetic wave and it achieves the impedance bandwidth of 11.9 % for the reflection coefficient less than -10 dB, the axial ratio (AR) bandwidth 2.2 % for AR less than 3 dB, and the LHCP peak gain of 6 dBi. The proposed antenna combines attractive features like low profile, low weight and low cost fabrication process.