SHUNT CAPACITIVE RF-MEMS SWITCHES TUNED FOR S-BAND APPLICATIONS
R. GADDI, A. GNUDI, B. MARGESIN, F. GIACOMOZZI

Abstract. Frequency limitations of capacitive RF-MEMS switches are tackled by designing coplanar transmission line based tuning networks for improving return loss in the S-band frequency range. Switches of relatively large dimensions, required for enough isolation at low frequencies, are realized in suspended gold membrane RF-MEMS technology. Input and output coplanar waveguides are integrated on the same high resistivity substrate. Measurement results confirm design specifications and circuit simulations, and demonstrate the achievement of return loss and isolation better that 20 dB in the 1-3 GHz band despite typical achieved capacitance ratios of less than 10.