A novel design of RF-MEMS phase shifter based on bridge-like coplanar waveguide

In this paper, a novel RF-MEMS phase shifter based on a rectangle bridge-like coplanar waveguide (BCPW) structure is proposed. The signal line of the coplanar waveguide (CPW) has symmetrical saw-shaped structures under the MEMS bridges above which covers the BCPW bridge. The CST software is used for the modeling, simulation and optimization the model of phase shifter from 30 to 40 GHz. Simulation and optimization results show that the proposed design with a 35 GHz central resonant frequency has a return loss less than -10 dB within about 2 GHz bandwidth range and for each RF MEMS switch-type bridge, as high as 75 degrees phase shift is realized. Compared with MEMS phase shifters without a BCPW bridge, S₁₁ performance can be improved by up to 10 dB, and interference among the adjacent components can be decreased.