EFFICIENT EPHEMERIS CODING

In one embodiment, a system is provided that is operable to: predict satellite states using historical satellite state data for at least one satellite of a satellite-based positioning system; derive sets of parameters representative of the predicted satellite states; differentially compress the sets parameters into sets of compressed parameters; transmit the sets of compressed parameters to a client device over a first communication channel; uncompress the sets of compressed parameters into sets of recovered parameters; selectively reconstruct at least one reconstructed satellite state in the client device using the sets of recovered parameters; and determine the position of the client device using the at least one reconstructed satellite state along with timing information of satellite data received over a second communication channel.