The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 03, 1998
Filed:
Aug. 14, 1996
Tadamasa Ushiroku, Ishikawa-ken, JP;
Murata Manufacturing Co., Ltd., Kyoto-fu, JP;
Abstract
A surface acoustic wave (SAW) filter has a ladder-shaped circuit in which first one-port SAW resonators are connected between an input terminal and an output terminal as series resonators and second one-port SAW resonators are connected as parallel resonators. The antiresonant frequency of the second one-port SAW resonators matches the resonant frequency of the first one-port SAW resonators. The distances between interdigital transducers and reflectors of the second one-port SAW resonators are specified such that a spurious component is generated at a frequency between the resonant frequency of the second one-port SAW resonators and the transmission band of the filter in order to improve attenuation characteristics in a blocking band in the vicinity of the transmission band.