Tunable high-Q dielectric loaded resonator and filter

A novel type of tunable high Q dielectric loaded resonator and its application to filters and multiplexers are presented. The tunable dielectric loaded resonator has high unloaded Q, wide tuning range, and high temperature stability by using the ring shape DR and dielectric tuning element. The tuning properties of the resonator, such as tuning range, spurious mode, unloaded Q, and effect on couplings are investigated. Several PCS band filters and multiplexers for CDMA base station applications were designed and tested. Excellent measured frequency responses were obtained.