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:
Oct. 21, 2008
Filed:
Nov. 20, 2006
Chi-shin Wang, Half Moon Bay, CA (US);
David Wang, Belmont, CA (US);
Wentao Zhang, Mountain View, CA (US);
Jun MO, San Jose, CA (US);
Lei Dong, Cupertino, CA (US);
Chi-Shin Wang, Half Moon Bay, CA (US);
David Wang, Belmont, CA (US);
Wentao Zhang, Mountain View, CA (US);
Jun Mo, San Jose, CA (US);
Lei Dong, Cupertino, CA (US);
SIRF Technology Holdihgs, Inc., San Jose, CA (US);
Abstract
The present invention provides methods and systems that enable a mobile navigation receiver to accurately determine its trajectory with non-current ephemeris in stand-alone mode. In an embodiment, the receiver computes the position for the same location using non-current ephemeris and current ephemeris at different time instances. The receiver then determines a position correction by finding the difference between these two computed positions, and applies this correction to the trajectory generated with non-current ephemeris to obtain a more accurate trajectory. In another embodiment, the receiver computes an initial position of the receiver using non-current ephemeris and finds the difference between the computed initial position and an accurate approximation of the initial position. The receiver then shifts the subsequent receiver trajectory computed using non-current ephemeris by the difference to obtain a more accurate trajectory.