JPS6437101A - Microwave filter - Google Patents

Abstract

PURPOSE:To miniaturize the whole of a filter by providing a drop-out part for coupling in a part of the outer conductor of a coaxial resonator and providing a drop-out part in the electrode on a substrate and arranging the coaxial resonator on the substrate so that respective drop-out parts are matched to each other. CONSTITUTION:An earth electrode 52 is formed on the upper face of a conductor substrate 51, and electrode drop-out parts 53 and 54 are formed in this earth electrode 52. Two prismatic dielectric coaxial resonators 55 and 56 are fixed to the upper face of the conductor substrate 51 and have inner conductors 55a and 56a formed on peripheral surfaces of through holes extended in the axial direction and outer conductors 55c and 56c formed on outside peripheral surface except voltage open end faces. Drop-out parts 57 and 58 for coupling are formed in a part of outer conductors 55c and 56c. These drop-out parts 57 and 58 are so formed that they are matched to electrode drop-out parts 53 and 54. Line of electric force and lines of magnetic force are connected between both resonators 55 and 56 to couple them to each other.