FILTER FOR MULTI-BAND ANTENNA SWITCHING MODULE

摘要

PURPOSE: A filter for a multiband antenna switching module is provided to improve characteristics of frequency attenuation, separation, and blocking by forming a capacitor between an input terminal and an output terminal. CONSTITUTION: A first circuit pattern(S10) printed on a first substrate, that is one arbitrary substrate of multilayer circuit boards, is connected to an input terminal receiving an input signal. A second circuit pattern(S20) printed on the first substrate is connected to an output terminal outputting a filtered input signal. A third circuit pattern(S30) printed on the second substrate is connected to the output terminal through a via hole. A fourth capacitor is formed by using the first circuit pattern and the third circuit pattern as opposing electrodes. A fourth circuit pattern(S40) is printed on the third substrate which is contiguous to the second substrate. A third capacity is formed by using the third circuit pattern and the fourth circuit pattern as the opposing electrodes.