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:
Jan. 10, 2012
Filed:
Jul. 02, 2009
Toshihiko Kawamoto, Sayama, JP;
Susumu Yoshimoto, Sayama, JP;
Toshihiko Kawamoto, Sayama, JP;
Susumu Yoshimoto, Sayama, JP;
Nihon Dempa Kogyo Co., Ltd., Tokyo, JP;
Abstract
To provide a duplexer which is small in size and excellent in separation characteristic of transmission/reception signals. An antenna port is disposed on a center of a rearward side in a disposition area of a duplexer, a high band side filter and a low band side filter are respectively disposed on a left side and a right side of the antenna port, a parallel arm at a last stage in the low band side filter, a parallel arm at a last stage in the high band side filter, a first signal port and a second signal port seen from the antenna port are positioned on a forward side of the antenna port, a ground side of a parallel arm on a front stage side of the parallel arm at the last stage in the low band side filter and a ground side of a parallel arm on a front stage side of the parallel arm at the last stage in the high band side filter are mutually connected via a conductive path formed on a piezoelectric substrate at a rearward side of the antenna port, and the parallel arms connected by the conductive path are positioned on the rearward side of the parallel arms at the last stages. Accordingly, a separation characteristic at a high band side is improved.