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:
Apr. 04, 1989
Filed:
Apr. 14, 1988
Applicant:
Inventors:
Toshimitsu Takahashi, Yokohama, JP;
Takashi Shiba, Yokosuka, JP;
Yuji Fujita, Yokohama, JP;
Jun Yamada, Yokohama, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03H / ; H03H / ;
U.S. Cl.
CPC ...
333194 ; 3103 / ; 333195 ;
Abstract
A group-type unidirectional surface acoustic wave filter composed of sending electrodes, reflecting electrodes and meander electrodes constituted by interdigital electrodes, respectively. As a phase shifter of the filter, a capacitive element is used. The geometrical configuration of the meander electrode is determined in accordance with geometrical phase difference. The filter enjoys low insertion loss with a simplified structure.