X-band RF MEMS tuned combline filter

A three-pole combline filter tuning from 8.2 to 11.3 GHz using RF MEMS switched capacitors is reported. This structure, measuring 2.85×2.15 mm2, allows 31% tuning with 11% 3 dB bandwidth for the four tuning states and insertion losses ranging from 4.4 to 6 dB.