LOW-LOSS TUNABLE RADIO FREQUENCY FILTER

摘要

A tunable RF filter is provided. The filter comprises a signal transmission path having an input and an output, a plurality of resonant elements disposed along the signal transmission path between the input and output, and a plurality of non-resonant elements coupling the resonant elements. The resonant elements are coupled together to form a stop band having a plurality of transmission zeroes corresponding to respective frequencies of the resonant elements, and at least one sub-band between the transmission zeroes. The non-resonant elements have susceptance values that locate at least one reflection zero within the stop band to create a pass band in one of the at least one sub-bands.