BROADBAND BANDPASS FILTER LOADED WITH THREE-BRANCH COUPLED MICRO-STRIP LINE

摘要

Provided is a broadband bandpass filter loaded with a three-branch coupled micro-strip line. The filter comprises two first micro-strip lines, two second micro-strip lines, two third micro-strip lines, two fourth micro-strip lines, two fifth micro-strip lines, two sixth micro-strip lines, two seventh micro-strip lines and two signal transmission ends which are all arranged on a surface of a dielectric plate. The broadband bandpass filter is bilaterally symmetrical about a first central axis, and the broadband bandpass filter is longitudinally symmetrical about a second central axis, wherein the first central axis is a connecting line between the middle points of upper and lower transverse frames of the broadband bandpass filter, and the second central axis is a connecting line between the middle points of left and right longitudinal frames of the broadband bandpass filter. The broadband bandpass filter in the present invention can realize a high selectivity for a passband signal, thereby introducing less noise and avoiding interference at a radio-frequency front end.