Electromagnetic behaviour of ohmic series RF MEMS switch for frequency reconfigurable antenna application

Abstract

RF switching devices are vital elements of all reconfigurable antennas as these are essential for redirecting the signals and current paths. This redirection of current changes the antenna's electrical length and subsequently changes in resonating frequencies are observed. RF MEMS switches possess an excellent electromagnetic characteristics as compared to other RF switches such as high isolation in off state and very much low insertion loss in on state. In this paper the ohmic series RF MEMS switch is designed and its critical parameters are analyzed. This ohmic RF MEMS switch is suitable for reconfigurable microstrip patch antenna operating at 1–10GHz. The effect of variation of design parameters are analyzed by varying the design parameters such as gap between the electrodes and thickness of cantilever. The pull in analysis is done to predict the operating voltage of the switch. The test prototype of switch is fabricated which is incorporated in reconfigurable antenna design and performance characteristics are presented in this paper.