A miniaturized half-mode siw based semi-circular antenna with arc-shaped slot

Asemi-circular antenna with the structure resembling that of a half-mode substrate integrated waveguide (HMSIW) is chosen and fed with co-axial feed to operate at 5.22 GHz within the IEEE 802.11a WLAN U-NII Low band. An arc-shaped slot is inserted in the middle of the parent antenna at an angle of θ = 80°, 90° and 100° in order to make the antenna compact. The miniaturized antenna so designed is found to operate at a center frequencyof 4.79 GHz for θ=80°, 4.61 GHz for θ=90° and 4.47 GHz for θ=100°. The shifts in the center frequencies observed are 430 MHz, 610 MHz and 750 MHz respectively from the center frequency of 5.22 GHz of the parent antenna. The various antenna parameters are simulated and studied extensively with the help of HFSS software.