FILTER ON SUPERFICIAL ACOUSTIC WAVES Russian patent published in 2000 - IPC

FIELD: electrical engineering. SUBSTANCE: device has piezoelectric sound duct having central phase-weighted counter-pin transducer connected to outlet lead of the filter and two identical lateral unidirectional counter-pin transducers based on U-shaped multibranch couplers positioned symmetrically relative to the central counter-pin transducer and connected in parallel to the inlet filter lead. The lateral counter-pin transducers have some metallization coefficient, electrode arrangement space, the number of electrode pairs, and the central phase-weighted counter-pin transducer has minimum electrode arrangement space, metallization coefficient, maximum length, number of electrode in every cross-section selected by applying some known relations. EFFECT: provided lower distortion level (non-uniformity) of frequency characteristic; reduced reflected signal level. 17 dwg