| 摘要 |
PROBLEM TO BE SOLVED: To provide a transversal SAW filter formed by arranging 3 IDT electrodes on a piezoelectric substrate at prescribed intervals whereby various characteristics of its pass band are improved without increasing the size of the filter. SOLUTION: In the transversal SAW filter, a first IDT electrode 1, second and third IDT electrodes 2, 3 arranged at both sides of the first IDT electrode are laid on the piezoelectric substrate. Stimulation electrodes of the first to third IDT electrodes are configured of split electrodes in pairs with two positive electrode fingers and two negative electrode fingers, weighting is applied to each stimulation electrode of either or both of the second and third IDT electrodes 2, 3, and the electrode structure of each of the second and third IDT electrodes 2, 3 is made asymmetrical relative to the center of the first IDT electrode 1. COPYRIGHT: (C)2006,JPO&NCIPI
|
