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:
Dec. 25, 2012
Filed:
Mar. 08, 2010
Toshihiko Kawamoto, Sayama, JP;
Susumu Yoshimoto, Sayama, JP;
Toshihiko Kawamoto, Sayama, JP;
Susumu Yoshimoto, Sayama, JP;
Nihon Dempa Kogyo Co., Ltd., Tokyo, unknown;
Abstract
A duplexer formed on a piezoelectric substrate includes a low band side filter and a high band side filter, and has an improved isolation characteristic in a pass frequency band of the high band side filter. Transmission and reception of signals are respectively performed from either of the low band side filter and the high band side filter and the other filter with respect to an input/output port. Series arms and parallel arms each formed of an elastic wave resonator form the low band side filter. A shield electrode is disposed close to either of the input/output port and a low band side filter port, and is grounded for capacitive coupling with same.