HMSIW-Based Miniaturized Sensing Antennas for S- and C-Band Applications

Abstract

In this letter, half-mode substrate integrated waveguide (HMSIW)-based low profile, rectangular slit(s) loaded compact semicircular antennas are presented as sensors to operate in the S- and C-band. The parent sensor is a HMSIW antenna initially designed at the center frequency of 5.22GHz with a gain of 6.4 dBi for the IEEE 802.11a WLAN U-NII low-band application. The semicircular antenna has metallic vias all along the semicircular edge, thereby making it perfect electrical conductor wall while the other side devoid of vias is a perfect magnetic conductor (PMC) wall. It is miniaturized upon placing rectangular slit(s) along the PMC edge, which reduces the fundamental resonant frequency to 4.68GHz and further to 3.85GHz with single and double slits, respectively. Both antennas radiate linearly polarized wave corresponding to TM010 mode with respective gain of 5.2 and 4.6 dBi. The antenna prototypes are fabricated using Arlon AD270 substrate and good agreement between simulated and measured results are obtained.