| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface acoustic wave high frequency filter having reduced insertion loss and simultaneously providing a high attenuation quantity out of bands. SOLUTION: A surface acoustic wave high frequency filter comprises surface acoustic wave resonators 52-54 of which the input/output terminals are connected in series to a signal line, and surface acoustic wave resonators 38-40 of which the one side of input/output terminals are connected to the above signal line and the other side are grounded. The surface acoustic wave resonator 52 is provided with interdigital electrode surface acoustic wave transducers 8, 9 connected in series, the surface acoustic wave resonator 53 is provided with interdigital electrode surface acoustic wave transducers 10, 11 connected in series, and the surface acoustic wave resonator 54 is provided with interdigital electrode surface acoustic wave transducers 12, 13 connected in series. Each of the surface acoustic wave resonators 52-54 connected in series to the signal line has four-times impedance of that of the surface acoustic wave resonators 38-40 connected in parallel to the signal line. COPYRIGHT: (C)2006,JPO&NCIPI
|
