Patent Number: 6,490,524

Title: Post-processing of NMEA data

Abstract: A method and system thereof for processing data in real time or post-processing, such as Global Positioning System (GPS) data that have been formatted in the National Marine Electronics Association (NMEA) format. In the GPS embodiment, uncorrected GPS data indicating an estimated position are computed by a receiver via signals from a first broadcaster (e.g., GPS satellites). Differential GPS (DGPS) data are received by the receiver via a signal from a second broadcaster (e.g., a GPS base station). A message is generated by the receiver when the signal from the second broadcaster is not received. The message contains information sufficient to identify the DGPS data stored by the second broadcaster needed to correct the uncorrected GPS data. The message and the uncorrected GPS data are stored by the receiver for subsequent processing. The DGPS data are retrieved from the second broadcaster, and the message is used to identify the DGPS data required to correct the uncorrected information. The uncorrected GPS data are correlated with the DGPS data and corrected.

Inventors: White; Eric S. (Mountain View, CA), Wetherbee; Lisa (Campbell, CA)

Assignee: Trimble Navigation Limited

International Classification: G01S 1/00 (20060101); G01S 5/14 (20060101); G01S 5/00 (20060101); G01C 021/26 ()

Expiration Date: 12/03/2019