Surface acoustic wave filter and method

Details Surface acoustic wave filter and method Surface acoustic wave filter and method

1994-03-04

1995-10-31

Pascal, Robert J.

Wave transmission lines and networks

Coupling networks

Electromechanical filter

333196, 310313B, H03H 964

Patent

active

054633613

ABSTRACT:
An electronic apparatus for receiving and filtering high frequency waves comprises a sequence of T electro-acoustic transducers each having multiple interdigital electrode fingers and a centerline located equidistant between its outermost electrode fingers. For a centerline-to-centerline distance of a first adjacent pair of transducers D.sub.1, and centerline-to-centerline distances of other adjacent pairs of transducers D.sub.2 to D.sub.T-1, then at least some of D.sub.2 to D.sub.T-1 differ from D.sub.1 by a non-integral number of wavelengths. The transducer array is symmetrical about a centerline and the number of fingers in each transducer varies, with an input or output transducer closer to either end of the sequence having more fingers than a like kind transducer nearer the center.

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