Tunable filter element, has adjustable impedance correction element connected parallel to adjustable capacitance

摘要

A tunable filter element (1) comprises a resonator (2) whose end (3) is joined to earth potential (5) and whose open end (4) is loaded by a first capacitance (9). The first capacitance can be adjusted for setting a resonance frequency of the filter element (1) and parallel to the first capacitance (9) is arranged an adjustable impedance correction element (15). An Independent claim is given for a tunable band-pass filter.