Development of 6–12 GHz evanescent–mode two–pole low–loss tunable bandpass filter

Abstract

Abstract-A very low loss, wide bandwidth, tunable evanescent-mode cavity band pass filter (BPF) with one-octave (6-12 GHz) tuning range is presented. In order to implement a very low insertion loss with wideband operation, a new coaxial feed structure is devised in the tunable BPF. Across the entire tuning range, the achieved insertion loss is less than 0.5 dB. The tunability is realized by using silicon microelectromechanical systems (MEMS) diaphragms with slits that are electrostatically actuated.