Pseudolite Augmented DGPS for Land Applications

T. Holden and T. Morley

Abstract:	As more and more applications are being developed that approach or exceed the limits of space-based GPS posi-tioning, other technologies, such as gyros and barometers, have been exploited in an attempt to meet stringent design requirements. The use of ground-based GPS transmitters (or pseudolites, for pseudo+satellites) can be used to fur-ther enhance the availability, accuracy, and reliability of the GPS-derived position solution. Pseudolites are a ma-ture technology that were used to validate the GPS con-cept at the Yuma Proving Ground prior to the launch of the first GPS satellites [Denaro, et al., 1980]. Since that time, significant advances have been made in the pseudo-lite signal structure and GPS user equipment. These ad-vances enable pseudolites to play a key role in demanding applications such as aircraft landing [Elrod, et al., 1994; Barltrop, et al., 1996; Bartone, 1996]. The role of pseu-dolites in other applications, such as marine navigation in constricted waterways, have also been investigated [Morley & Lachapelle, 1997]. This paper reviews the Stanford Telecom GuideNetä concept, where a pseudolite is used not only as an extra ranging source to increase the availability and accuracy of differential GPS, but also as a differential data link. This technology is particularly suited to any application that faces a challenging GPS environment, such as positioning in an area that experiences blockages of GPS signals due to topography or man-made structures. Applications with implementation constraints (such as solution availability, and reliability) or severe design constraints (such as space, weight, or power limitations on the user platform) can benefit from pseudolite augmentation of GPS.
Published in:	Proceedings of the 10th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GPS 1997) September 16 - 19, 1997 Kansas City, MO
Pages:	1397 - 1404
Cite this article:	Holden, T., Morley, T., "Pseudolite Augmented DGPS for Land Applications," Proceedings of the 10th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GPS 1997), Kansas City, MO, September 1997, pp. 1397-1404.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In