Patent ID: 9647637
Date: 2017-05-09
CPC Classifications: H03H

Claim:
1. A filter working with surface acoustic waves comprising: a piezoelectric substrate (SU) providing an acoustic track on the surface of the substrate; a first transducer (IDT a second transducer (IDT a reflector arranged between the first and second transducers having a second mean finger period (p wherein the first and second transducers (IDT wherein a width of each transducer finger and a spacing between the fingers of a respective pair of adjacent transducer fingers are increasing in a transversal direction, the transversal direction being normal to a longitudinal direction of the acoustic track but within the substrate plane, the transducers being adapted to provide a relative bandwidth of the transducer of at least 8%, and wherein both the transducers (IDT a shielding structure (SH) between the first and second transducers (IDT