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:
Mar. 01, 2005
Filed:
Oct. 21, 2002
Wataru Ohashi, 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, an antenna, a transmitting filter, a branching line and a receiving filter. The antenna is coupled to the antenna terminal. The transmitting filter is coupled to the antenna terminal. The transmitting filter receives an electrical power. The branching line is coupled to the antenna terminal. The branching line has a first length that is longer than λ/4 length so that the electrical power received by the transmitting filter when the antenna terminal is opened is smaller than when the antenna terminal is terminated, wherein λ is a wave length of a center frequency of transmitted and received bands of the surface acoustic wave filter. The receiving filter is coupled to the branching line.