HARMONIC FILTER SUPPRESSING HIGH FREQUENCY HIGHER HARMONIC OF ACOUSTIC SURFACE TRANSVERSE WAVE

摘要

A harmonic filter suppressing a high frequency higher harmonic of an acoustic surface transverse wave, comprising a chip (1), packaged in a surface-mount package (21), and comprising two or more acoustic surface transverse wave filters arranged thereon, wherein all of the acoustic surface transverse wave filters are serially connected to one another, and finger widths of middle short gratings (103), (108) of each of the acoustic surface transverse wave filters are less than finger widths of slanted finger interdigital transducers (102), (104), (107), (109). The harmonic filter provides enhanced out-of-band suppression, improves performance of out-of-band suppression, and meets a requirement of providing high out-of-band suppression when operating in a high frequency. Components of the harmonic filter may be arranged according to two or more connection types including arranging the components along a propagation direction of an acoustic wave, or arranging the components in parallel and separated by a distance, thereby reducing a space taken up by the components.