A novel design of 4-bit distributed MEMS transmission line (DMTL) phase shifter using an RF shunt capacitive MEMS switch for phased array antenna

In this paper, coplanar waveguide (CPW) of dimension (0.2/1.6/0.2) mm has been used as the transmission line on which a ten number of Capacitive Shunt RF MEMS Switches are periodically spaced in order to achieve appreciable phase shift. The dimensions of the transmission line may be designed to provide a transmission line of 50Ω characteristic impedance periodically. A 4-bit Distributed MEMS transmission line (DMTL) phase shifter has been designed and provides the phase shifts of 900/3540/3360 depending on the combination of bits being used. The frequency of the complete designed is taken as 3-4 GHz of S-band and resonant frequency of around 3.55 GHz. A highly integrated complete structure has been designed on FR4-epoxy substrate having relative permittivity of 4.4 and has the area of 164.17 × 85.49 mm² only. The designed and analysis is performed by using High Frequency Structural Simulator (HFSS version 13.0) software.