Concentric Ring Structured Reconfigurable Antenna using MEMS Switches for Wireless Communication Applications

This paper proposes a reconfigurable circular microstrip antenna to serve the wireless communication applications that make use frequency bands such as ISM (Industrial Scientific and Medical), WLAN (Wireless Local Area Network), UMTS (Universal Mobile Telecommunications Service). Reconfigurability is achieved with the help of four MEMS (Micro-Electro-Mechanical Systems) switches to change the frequency and radiation properties of the antenna. By choosing either of the two states of each of the MEMS switches, the radius of the circular patch is varied and subsequently the operating resonant frequency. This gives rise to multiple configurations of the antenna to serve for different wireless applications. Defected Ground Structure is employed in this design to lower the resonant frequency and improve the bandwidth. Concentric rings are implemented along with a core circular patch in order to increase the radiating area of the patch in association with the MEMS-based switches to operate in toggle mode of ON and OFF. The concentric rings also helping in obtaining dual-frequency behavior of the antenna and the measured results are showing good agreement with the simulation results.