Silicon-based substrate-integrated waveguide-based tunable band-pass filter using interdigital MEMS capacitor

A novel method for designing miniaturized tunable BPF filter is proposed on the basis of the SIW technology. By loading MEMS cantilevers on the metal fingers´ surface of the IDC, passband of the filter can be differently generated. The proposed structure allows relatively independent control the center frequency and the coupling coefficient. This filter is showing advantages in terms of compact size, good selectivity and stopband rejection, as well as the easy integration capability with other circuits. The proposed filter has the continuously tuning range between 23.6 GHz and 25.6 GHz with insertion between 4.59 dB to 4.13 dB.