Tunable and Dual Band Slot Loaded Hexagonal Microstrip Antenna for Wireless Communications

This article describes the design of single layer dual frequency microstrip antenna for IEEE 802.11b/Bluetooth and WiMAX applications. The new configuration of the antenna is achieved by using open hexagonal ring slot placed at the boundary of the hexagonal patch. The proposed dual frequency antenna exhibits two adjacent resonant modes with the same plane of polarization, radiation characteristics, and impedance characteristics and these modes are excited at frequencies near the fundamental mode TM11 of the hexagonal patch without a slot. Compared with the conventional hexagonal patch, the proposed antenna can achieve a large amount of size reduction. It has also been observed that by controlling the width of slot and distance R1, the two frequencies f1 and f2 can have frequency ratio (f2/f1) in the range between 1.28 and 1.44. The antenna is simulated and analyzed using Ansoft HFSS.