Patent ID: 6861927

Claim:
A longitudinally coupled leaky surface acoustic wave resonator filter comprising: a piezoelectric substrate suitable for propagating a leaky surface acoustic wave; a plurality of interdigital transducers disposed upon the substrate in an acoustically cascading manner along a longitudinal axis of surface acoustic wave propagation so as to form a longitudinally coupled leaky surface acoustic wave resonator filter track having one or more resonant cavities disposed between adjacent interdigital transducers within the track, wherein a chirping of an electrode pitch of interdigital transducer electrodes in a vicinity of the one or more resonant cavities differs from an electrode pitch in a central portion of the interdigital transducers forming the one or more resonant cavities for reducing a phase discontinuity in the vicinity of the resonant cavity, thus reducing a bulk acoustic wave scattering loss; and a reflective element disposed at opposing ends of the longitudinally coupled resonator filter track.