Design and optimisation of a novel structure capacitive RF MEMS switch to integrate with an antenna to improve its performance parameters

Abstract

In this study, a step-down structured switch is designed and compared with and without optimised dimensions to increase the isolation and to lower the pull-in-voltage with respective electromechanical and electromagnetic characteristics. The optimised switch is designed to operate only in K-band frequencies with the high isolation of −54.17 dB at the centre frequency of 22 GHz. The antenna using MEMS switch exhibits a frequency shift of 1.5 GHz from the first case to the second case and 7.4 GHz in the third case due to change in radiating length of patch antenna operating at different ON/OFF combinations of switches whereas the antenna with PIN diode shifts the frequency approximately same, but the low isolation of PIN diode makes it less immune to noise.