Novel Design for RF MEMS Capacitive Shunt Switch in K and Ku Bands

A novel design for RF MEMS Capacitive Shunt Switch with operating bandwidth in the K and Ku bands is presented in this paper. The novel MEMS switch has got lower insertion loss than a normal switch and there is no compromise on the isolation and the operating bandwidth of the switch. The resonant frequency of the proposed switch is kept constant near 20GHz which is the midpoint of the bandwidth of the switch. A comparative study of a normal switch and the proposed switch is done. The improvement in design has been achieved by introducing discontinuities in the coplanar waveguide both in the central conductor and the ground planes. The discontinuities are represented in terms of equivalent lumped parameters. A new method of obtaining the lumped parameters of coplanar waveguide step discontinuities in the central conductor and ground planes using full wave electromagnetic simulation is also presented.