Patent ID: 6720849
Filing Date: 2004-04-13
Classification: H01P

Abstract:
A high frequency filter comprising:a dielectric substrate; a ground electrode arranged on a main surface of the dielectric substrate; a conductive through-hole; and a plurality of microstrip line resonators formed on the other main surface of the dielectric substrate, one end of each resonator being grounded via the through-hole, wherein the microstrip line resonators share the through-hole for grounding the one end of each resonator to be mutually coupled via the inductance of the through-hole, and wherein an odd-mode resonant frequency is determined by lengths of the plurality of microstrip line resonators and an even-mode resonant frequency is determined by lengths of the plurality of microstrip line resonators and the inductance of the through-hole such that a bandwidth of the filter is adjusted by a value of the inductance of the through-hole.