Tunable ceramic filters

A tunable dielectrically loaded waveguide cavity filter comprising:

• a plurality of cavities coupled in series, each cavity having a pair of opposed ceramic resonators disposed therein, at least one of the resonators being moveable;
• and
• a plurality of stepper motors each coupled to a different one of the ceramic resonators that are moveable and each configured to move the respective ceramic resonator that is moveable.

A tunable dielectrically loaded waveguide cavity filter having a cavity, a ceramic puck disposed in the cavity, and a graphical display for graphing a bandpass frequency characteristic of the tunable filter.

A method for tuning a dielectrically loaded waveguide cavity filter, the method comprising the steps of:

• tuning the filter to a first frequency by moving at least one of two opposed ceramic pucks within a cavity of the filter;
• and
• tuning the filter to a second frequency at least 2 GHz away from the first frequency by moving the at least one ceramic puck within the cavity of the filter.

A tunable dielectrically loaded waveguide cavity filter comprising:

• a plurality of waveguide cavities coupled in series, each of the cavities including a pair of opposed ceramic pucks disposed within the cavity;
• and
• a plurality of stepper motors, the stepper motors each being coupled to one of the ceramic pucks for moving the respective ceramic pucks within the respective cavities.

The tunable dielectrically loaded waveguide cavity filter of clam 18, wherein the plurality of stepper motors are each coupled to the respective ceramic pucks such that the respective ceramic pucks move within the respective cavities without rotation.