A Testing Methodology for GPS Phase Multipath Mitigation Techniques

D. Bétaille

Abstract:	There have been a number of attempts in recent years to mitigate the effects of GPS phase multipath. In general, these have led to only small improvements in the accuracy of phase measurements. In order to assess rigorously the effectiveness of these developments, it is necessary to establish a well-defined testing methodology. This paper addresses this issue and reports on a specific set of experiments that took place at the LCPC near Nantes in France as part of the author's PhD programme. The first section of this paper summarises the main aspects of the theory of multipath, and the second section deals with the modelling of multipath phase error in double differences. This model is applied to confirm the multipath effects observed during several static and kinematic tests that have been specifically designed to generate multipath by means of a large metallic panel. The SESSYL test bed at the LCPC was used for the kinematic tests, and its background multipath effects have been identified. This is reported in the third section. In the fourth section, the methodology proposed in this paper has been applied, as an example, to a pair of GPS receivers (two Leica System 500 units) that have been modified to incorporate a new phase multipath mitigation firmware. A series of tests have been carried out to assess the capabilities of this firmware both with lightweight and choke-ring antennas. These tests have been carried out with SESSYL in May and June 2002.
Published in:	Proceedings of the 16th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GPS/GNSS 2003) September 9 - 12, 2003 Oregon Convention Center Portland, OR
Pages:	2151 - 2162
Cite this article:	Bétaille, D., "A Testing Methodology for GPS Phase Multipath Mitigation Techniques," Proceedings of the 16th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GPS/GNSS 2003), Portland, OR, September 2003, pp. 2151-2162.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In