Assessment of GEO Augmentation for GPS III Constellations

R.H. Clark, J.H. Drake

Abstract:	Several concepts are defined and analyzed to evaluate the potential benefits for the use of GEO satellites to augment performance of candidate MEO constellations comprising future GPS constellations. GEO satellites offer potential benefits for improving selected navigation services for regional users. Two types of augmentation are considered. The first assumes that GEO augmentation complements navigation signals of the existing GPS network of satellites by the addition of more ranging source signals. A second more capable geosynchronous augmentation provides an autonomous overlay of new signals that provide navigation capabilities or services not available from the pre-existing network of satellites. The autonomous overlay provides acceptable dilution of precision geometry via additional signals independent of the existing GPS network in a limited region. It also provides signals, which complement the old network, through additional navigation sources for existing users within the region. Performance metrics for a variety of architectures, measures of service availability, and navigation accuracy are developed. Initial assessments of performance and cost are presented along with overall concept assessments. Regional performance achievable with GEO augmentation of the present constellation is compared with capability of a larger, high-performance, all-MEO GPS constellation. Comparisons are made at elevation mask angles of both 5 and 20 degrees to provide additional assessment criteria.
Published in:	Proceedings of the 2003 National Technical Meeting of The Institute of Navigation January 22 - 24, 2003 Disneyland Paradise Pier Hotel Anaheim, CA
Pages:	657 - 662
Cite this article:	Clark, R.H., Drake, J.H., "Assessment of GEO Augmentation for GPS III Constellations," Proceedings of the 2003 National Technical Meeting of The Institute of Navigation, Anaheim, CA, January 2003, pp. 657-662.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In