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:
Feb. 01, 2000
Filed:
Nov. 07, 1997
Toshio Ishizaki, Kobe, JP;
Atsushi Sasaki, Toyonaka, JP;
Yuki Satoh, Katano, JP;
Hiroshi Kushitani, Izumisano, JP;
Hideaki Nakakubo, Souraku-gun, JP;
Toshiaki Nakamura, Nara, JP;
Kimio Aizawa, Ikoma, JP;
Takashi Fujino, Izumi, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A dielectric antenna duplexer used in a high frequency radio device such as a portable telephone, and a dielectric filter for forming the duplexer of the SIR (stepped impedance resonator) composed by cascade connection of first transmission lines having one end grounded and second transmission lines having one end open and lower in characteristic impedance than in the first transmission lines, first transmission lines and second transmission lines are individually coupled in electromagnetic field, thereby forming an antenna duplexer and a dielectric filter of small insertion loss, high bandwidth selectivity, excellent band pass characteristic, and low cost.