Tunable dielectric resonator bandpass filter with embedded MEMS tuning elements

This paper presents a novel approach for constructing a tunable dielectric resonator bandpass filter by using the micro-electromechanical system (MEMS) technology. The tunability is, achieved by unique MEMS tuning elements to perturb the electrical and magnetic fields surrounding the dielectric resonators. The use of such elements as a tuning mechanism results in a wide tuning range at a relatively low tuning voltage and fast tuning speed. A three-pole tunable dielectric resonator bandpass filter is designed, fabricated, and tested. The experimental filter has a center frequency of 15.6 GHz, a 1% relative bandwidth, and an unloaded Q of 1300. A tuning range of 400 MHz is obtained by using MEMS tuning elements with 2 mm x 2 mm tuning disks. The measured results demonstrate the feasibility of the proposed concept.