Patent ID: 9559398
Date: 2017-01-31
CPC Classifications: H01P,Y10T

Claim:
1. A multi-mode cavity filter comprising: a dielectric resonator, said dielectric resonator including a piece of dielectric material, said piece of dielectric material having a substantially cubic shape having six sides, whereby said dielectric resonator is capable of supporting multiple degenerate resonant modes in parallel, said piece of dielectric material being free of cutouts and coupling structures extending therewithin; a covering of conductive material on five of said six sides of said piece of dielectric material, wherein said sixth side of said piece of dielectric material is not covered by said conductive material except around a perimeter thereof so as to form an aperture allowing signals to be input to and output from said dielectric resonator; a planar coupling structure extending adjacent to said sixth side of said piece of dielectric material within said aperture for coupling to said multiple degenerate resonant modes in parallel for at least one of coupling input signals to the dielectric resonator and extracting filtered output signals from the dielectric resonator; and a printed circuit board structure having at least one ground plane layer, said sixth side of said piece of dielectric material not covered by said conductive material being in contact with said at least one ground plane layer of said printed circuit board structure so that said at least one ground plane layer is electrically coupled to the covering of conductive material around said perimeter of said sixth side, said planar coupling structure being completely between said piece of dielectric material and said printed circuit board structure, said at least one ground plane layer covering said aperture to minimize any leakage of electromagnetic energy from said dielectric resonator.