Patent ID: 6297715
Filing Date: 2001-10-02
Classification: H01P

Abstract:
A microwave filter comprising:a composite microwave resonator comprising a cavity resonator and a dielectric resonator element disposed within the cavity resonator that comprises a material having a high dielectric constant and a high Q, the resonator element having a self-resonant frequency, the dimensions of the cavity resonator being selected to cause the composite resonator to have a first order resonance at a frequency near the self-resonant frequency;first tuning apparatus disposed along a first axis for tuning the composite resonator to resonance in a first resonant mode;second tuning apparatus disposed along a second axis that is substantially orthogonal to the first axis for tuning the composite resonator to resonance in a second resonant mode;mode coupling apparatus for adjusting the amount of energy coupled between the first and second resonant modes;input coupling apparatus for coupling microwave energy into the cavity resonator, and which is disposed at an angle between 0 degrees and .+-.180 degrees relative to the first axis defined by the first tuning apparatus;and wherein at least one of the input and output coupling apparatus is disposed at an angle that is different from the first or second axes to provide variable input/output coupling, such that at least one of the input and output coupling apparatus couples to first and second resonant modes.