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. 13, 2004
Filed:
Apr. 24, 2001
Applicant:
Inventors:
James G. Eagleson, San Jose, CA (US);
William E. Blasdell, San Jose, CA (US);
Arthur E. Anderson, III, Sunnyvale, CA (US);
Nikola Cargonja, San Carlos, CA (US);
Assignee:
Savi Technology, Inc., Sunnyvale, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G08G 1/09 ; H04Q 5/22 ; G08B 1/314 ;
U.S. Cl.
CPC ...
G08G 1/09 ; H04Q 5/22 ; G08B 1/314 ;
Abstract
A signpost ( ) transmits low frequency signals to a beacon tag ( ), which in turns transmits high frequency signals containing a signpost code from a received signpost signal to a reader ( ). The signpost can be mounted on one mobile device and the beacon tag on another mobile device, in order to determine when those mobile devices are in close proximity. Further, a sensor ( ) can be provided to detect the presence of a mobile device, and to cause the signpost to change the signpost code in its transmitted signals.