Electronic tuning of a dielectric resonator at microwave frequencies

Deals with the electronic tuning of a 950 MHz shielded dielectric resonator (DR) operating in its fundamental model by use of a loop-varactor circuit. It is shown that this tuning mechanism leads to considerable degradation of unloaded Q and jumps in resonant frequency. A tuning range of 1 MHz with unloaded Q in excess of 9000 were obtained.