| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface acoustic wave filter capable of reducing undulation shown in an insertion loss property to an input/output impedance in a passband, and improving VSWR. SOLUTION: A surface acoustic wave filter 1 includes surface acoustic wave devices 10, 20, disposed on a piezoelectric substrate 2 and having a plurality of resonators coupled along the transmission direction of a surface acoustic wave, with cascade connection in a plurality of stages. The surface acoustic wave device 10 includes IDT electrodes 11, 14a, 14b and electrodes 13a, 13b of an inserted reflector, and the surface acoustic wave device 20 includes IDT electrodes 21, 24a, 24b and electrodes 23a, 23b of an inserted reflector. The IDT electrodes 14a, 14b are connected to the IDT electrodes 24a, 24b through wiring patterns 32a, 32b, and the electrodes 13a, 13b of the inserted reflector are connected to the electrodes 23a, 23b of the inserted reflector through grounding patterns 31a, 31b. COPYRIGHT: (C)2007,JPO&INPIT
|
