MICROWAVE BAND-PASS FILTER

摘要

PROBLEM TO BE SOLVED: To provide a microwave band-pass filter equipped with a plurality of resonators including at least one coaxial resonator and enabling sufficient suppression of spurious or higher passbands without requiring an extra space for components. SOLUTION: The microwave band-pass filter includes a plurality of combined resonators including at least one coaxial resonator. To suppress higher or spurious passbands, the filter has a center hole 9 extended from the upper edge of an internal conductor 6 of at least one coaxial resonator through at least part of the length of the internal conductor and comprising a waveguide part, and the cut-off frequency is higher than the passband of the band-pass filter. The waveguide part includes low loss dielectric materials with a sufficiently high dielectric constant in its upper part so that the cut-off frequency of the waveguide part is lower than a first higher order response of the band-pass filter. COPYRIGHT: (C)2007,JPO&INPIT