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. 19, 2002
Filed:
Sep. 21, 2000
Masayuki Atokawa, Kanazawa, JP;
Abstract
A duplexer and a communication apparatus incorporating the same which are suitable for use in communication systems with wide frequency bands and narrow separations, and which can be miniaturized while having satisfactory characteristics. The duplexer has a transmission filter constituted of a variable frequency filter in which PIN diodes are connected to dielectric resonators and a reception filter constituted of two surface acoustic wave filters and a switching circuit. In the transmission filter, one of the higher and lower sides of a transmission frequency band can be selected according to a voltage applied to a first voltage control terminal. In addition, in the reception filter, one of the two surface acoustic wave filters can be selected according to a voltage applied to a second voltage control terminal.