Dielectric filter

A dielectric filter, comprising:

• a housing, wherein a resonant slot is disposed on the housing, a support portion is disposed in the resonant slot, and the support portion encloses to form an intermodulation groove at a slot bottom of the resonant slot;
• a dielectric resonator, wherein the dielectric resonator is mounted on the support portion and covers a groove opening of the intermodulation groove, a plurality of adjustment holes are disposed on the dielectric resonator, and the plurality of adjustment holes communicate with the intermodulation groove;
• a cover plate, wherein the cover plate is connected to the housing, covers an opening of the resonant slot, and is spaced apart from the dielectric resonator;
• and
• a tuning structure, wherein the tuning structure is connected to the cover plate, and each of the plurality of adjustment holes is configured with one tuning structure;
• wherein the support portion comprises an annular boss and an annular bushing, the annular boss is integrally formed with and connected to the slot bottom and/or a slot wall of the resonant slot, the annular bushing is mounted in the annular boss, and the dielectric resonator is mounted on the annular bushing.