FILTER CIRCUIT FOR HIGH FREQUENCY USING ACTIVE INVERTER WHICH HAS FEEDBACK CIRCUIT

摘要

PURPOSE: A filter circuit for high frequency using active inverter which has a feedback circuit is provided to amplify desired frequency component by removing unnecessary frequency component for each kind of transceivers. CONSTITUTION: In a filter circuit for high frequency, an active inverter(303) is connected between resonators(302,307) and resonators(304,313). The active inverter(303) has the first serial feedback circuit(310), the second serial feedback circuit(311), the third serial feedback circuit(312) and a parallel feedback circuit(308). The second serial feedback circuit(311), an active device(309) and the third serial feedback circuit(312) are coupled each other. The first serial feedback circuit(310) is connected to the active device(309) to form the parallel feedback circuit(308). Therefore the filter circuit for high frequency amplifies desired frequency component by removing unnecessary frequency component for each kind of transceivers.