GROUP DELAY FILTER CAPABLE OF CONTROLLING ATTENUATION CHARACTERISTICS BY USING TWO CROSS-COUPLINGS

摘要

PURPOSE: A group delay filter is provided to easily control flatness and attenuation characteristics of group delay filter in a pass band by using two cross-couplings. CONSTITUTION: A group delay filter comprises a housing(310) having an open top, and which has a plurality of cavities, coupling windows and cross-coupling windows; a plurality of resonators(312a to 312i) arranged in the centers of the cavities and designed to resonate at a preset frequency; an input terminal(311) and an output terminal(315) arranged at the side surface of the housing such that a microwave signal is input/output to/from the group delay filter; an input coupling loop and an output coupling loop for interconnecting input and output terminals and the resonators, and which allow for passage of only a predetermined band; a cover coupled to the top of the housing so as to cover the open top of the housing; and a plurality of fine control members(316a to 316h,317a,317b,318a to 318h) arranged on the cover, and which control characteristics of the group delay filter. Attenuation characteristics of the group delay filter are controlled in accordance with the cross-coupled volume of the first and second cross-coupling windows.