Tunable microwave bandpass filter by relative rotation of an insert section and a dielectric element

摘要

A bandpass filter for microwave-frequency wave which is frequency tunable, comprises at least one resonator. Each resonator comprises a cavity having a conducting wall substantially cylindrical in relation to an axis Z, and at least one dielectric element disposed inside the cavity. The resonator resonates on two perpendicular polarizations having respectively distributions of the electromagnetic field in the cavity that are deduced from one another by a rotation of 90° and according to one and the same frequency. The wall of the cavity comprises an insert section facing the element having a different shape from a section not situated facing the element. The insert section and the element are able to perform a rotation with respect to one another in relation to the axis Z so as to define at least a first and a second relative position differing by an angle substantially equal to 45° to within 20°.