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:
Jun. 28, 2005
Filed:
Oct. 21, 2002
Kenichi Anasako, Tokyo, JP;
Yoshiaki Fujita, Kanagawa, JP;
Hisanori Ehara, Tokyo, JP;
Tomokazu Komazaki, Saitama, JP;
Kenichi Anasako, Tokyo, JP;
Yoshiaki Fujita, Kanagawa, JP;
Hisanori Ehara, Tokyo, JP;
Tomokazu Komazaki, Saitama, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
A surface acoustic wave filter includes an antenna terminal, a transmitting filter and a variable branching line both of which are coupled to the antenna terminal and a receiving filter coupled to the variable branching line. The transmitting filter has a first end series-arm SAW resonator, a second end series-arm SAW resonator, a middle series-arm SAW resonator coupled between the first and second end series-arm SAW resonators and parallel-arm SAW resonators. Each of the first and second end series-arm SAW resonator has a first resonance frequency. The middle series-arm SAW resonator has a second resonance frequency that is higher than the first resonance frequency.