This article presents an inductively loaded radio frequency (RF) microelectromechanical systems (MEMS) reconfigurable filter with spurious suppression implemented using packaged metal-contact switches. Both simulation and measurement results show a two-state, two-pole 5% filter with a tuning range of 17% from 1.06 GHz to 1.23 GHz, an insertion loss of 1.56-2.28 dB and return loss better than 13 dB over the tuning range. The spurious passband response in both states is suppressed below 220 dB. The unloaded Q of the filter changes from 127 to 75 as the filter is tuned from 1.06 GHz to 1.23 GHz. The design and full-wave simulation of a two-bit RF MEMS tunable filter with inductively loaded resonators and monolithic metal-contact MEMS switches is also presented to prove the capability of applying the inductive-loading technique to multibit reconfigurable filters. The simulation results for a two-bit reconfigurable filter show 2.5 times improvement in the tuning range compared with the two-state reconfigurable filter due to lower parasitics associated with monolithic metal-contact MEMS switches in the filter structure. 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE 19: 692-700, 2009.
