The present invention provides methods and system for enabling a
standalone navigation receiver capable of generating receiver specific
predicted satellite orbits based on historical navigation data collected
by and stored in the receiver. Thus, the navigation receiver is able to
use the predicted satellite orbits to obtain better Time-To-First-Fix
(TTFF) and position accuracy without the need of connecting to a remote
server and the associated communications system. In an embodiment, a
standalone navigation receiver having sufficient memory collects
navigation data from navigation satellites and generates predicted
satellite orbits using the collected navigation data. Under weak signal
conditions when decoding of the navigation data is not possible, the
receiver uses the predicted satellite orbits to predict the accurate
satellite positions or the set of ephemeris and the associated
pseudoranges. The predicted orbits may be accurate for several days
without the reception of broadcast ephemeris.