Coaxial cavity resonator

A coaxial cavity resonator comprising, an enclosed cylindrical outer conductor having opposite end walls, an inner cylindrical conductor coaxial with the outer conductor and having stepped first and second portions in the direction of propagation of microwave energy, said first portion being between said second portion and one of said end walls and having distributed inductances, said second portions having distributed capacitances and spaced from the other of said end walls to form a lumped capacitance therebetween, and a body of dielectric material surrounding said second portion, the dielectric constant of said material having a negative temperature coefficient.

A microwave circuit component comprising, an outer conductor defining a cavity therein, an inner cylindrical conductor shaped into first and second portions having respective first and second transverse dimensions, means for coupling microwave energy to the outer and inner conductors to permit same to propagate axially through said cavity, said first portion being in electrical contact with the outer conductor to provide short-circuit reflection of the microwave energy from the point of said contact and having smaller transverse dimensions than said second portion, said second portion being in open-circuit relation with the outer conductor to provide open-circuit reflection of the microwave energy from the end thereof opposite to the first portion, means for connection to an external circuit for extracting the microwave energy from said cavity, said first and second portions being axially and transversely dimensioned to provide resonance at a predetermined microwave frequency, and a dielectric body having a dielectric constant with a negative temperature coefficient disposed to circumferentially encircle a part of said second portion.