FILTER ON SURFACE ACOUSTIC WAVES WITH QUASI-FAN CONVERTERS Russian patent published in 2001 - IPC

FIELD: radio electronics. SUBSTANCE: invention can find use in filters of intermediate and carrier radio frequencies for selection of signals in radio telephones, pagers, mobile communication systems, etc. Surface acoustic waves propagating towards output converter and transforming in it to electric signals extracted across load are excited in piezoelectric substrate with supply of electric signal to input converter carrying electrodes. Periods and widths of electrodes vary along apertures of corresponding input converters. Input and output converters are divided along their apertures into parallel acoustic channels whose number in each converter is chosen from given relations. Electrodes in each acoustic channel are placed perpendicular to direction of propagation of surface acoustic waves. Periods and widths of electrodes are constant and apertures of acoustic channels are also chosen from given relations. Like electrodes of adjacent acoustic channels are electrically intercoupled by connection jumpers. Connection jumpers are made in the form of trapezium, rectangle or set of rectangles partially overlapping like electrodes of adjacent acoustic channels. Division of input and output converters into limited number of acoustic channels in agreement with invention makes it possible to diminish distortion of frequency characteristics of filter on surface acoustic waves and to simplify its manufacture. EFFECT: diminished distortion of preset frequency characteristics and simplified manufacture of filters. 3 cl, 6 dwg