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. 27, 2016
Filed:
Dec. 09, 2011
Takahide Terada, Tokyo, JP;
Hiroshi Shinoda, Tokyo, JP;
Kazunori Hara, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An electromagnetic wave propagation mediumextends in the propagation direction of an electromagnetic wave and has an electromagnetic wave propagation space sandwiched between conductors in the direction perpendicular to the electromagnetic wave propagation direction. A base unitand multiple terminalsare placed on the electromagnetic wave propagation medium. When the position of a terminalis detected, the base unittransmits a position detection signal through the electromagnetic wave propagation mediumto the terminal. This position detection signal is attenuated more heavily during its propagation through the electromagnetic wave propagation mediumthan a communication signal for use in normal communication is. The signal strength of the position detection signal drops as it moves away from the base unit. Hence the position of each terminalcan be detected based on the signal strength of the position detection signal received by each terminal