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:
Aug. 08, 2006
Filed:
Jan. 09, 2006
James M. Janky, Los Altos, CA (US);
David G. Bird, Thornton, CO (US);
Ann Ciganer, San Mateo, CA (US);
James M. Janky, Los Altos, CA (US);
David G. Bird, Thornton, CO (US);
Ann Ciganer, San Mateo, CA (US);
Trimble Navigation Limited, Sunnyvale, CA (US);
Abstract
A GPS information service system for providing supplemental GPS location correction and signal acquisition information to subscribers. A GPS information server broadcasts GPS information encrypted with subscription keys. Remote GPS subscription unit receive the key enablers for the subscription keys in service activation (SAM) messages for the services for which they have subscribed and then use the subscription keys to decrypt the GPS information. In order to prevent unauthorized use, the SAM messages have signatures derived from identifications of the remote GPS subscription units using an unsymmetrical signature algorithm.