AI Article Synopsis
- GNSS multipath remains a challenge for improving accuracy despite existing mitigation techniques, necessitating further research.
- The concept of Fresnel zones is utilized to enhance positioning by identifying and excluding potentially diffracted signals based on obstructions in the environment.
- Analysis shows that a 50% overlap between Fresnel zones and reflectors can significantly induce multipath effects, contradicting some established theoretical assumptions.
Article Abstract
GNSS (Global Navigation Satellite Systems) multipath has been subject to scientific research for decades and although numerous methods and techniques have already been developed to mitigate this effect, it is still one of the accuracy-limiting factors in many GNSS applications. Since multipath is highly dependent on the individual antenna environment, there is still a need for new methods and further investigations to increase the understanding of this systematic effect. In this paper, the concept of Fresnel zones is applied to two different aspects of multipath. First, Fresnel zones are determined for the line-of-sight transmission between satellite and receiver. By comparing the boundary of the Fresnel zones to an obstruction adaptive elevation mask, potentially diffracted signals can be identified and excluded from the position estimation process. Both the percentage of epochs with fixed ambiguities and the positioning accuracy can be increased by the proposed method. Second, Fresnel zones are used to analyze the multipath induced by a horizontal and spatially-limited reflector. The comparison of simulated and real signal-to-noise (SNR) observations reveals a relationship between the percentage of the overlap of the Fresnel zone and reflector and the occurrence of multipath. It is found that an overlap of 50% is sufficient to induce multipath effects. This is of special interest, since this does not confirm theoretical assumptions of the multipath theory.
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|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6339234 | PMC |
| http://dx.doi.org/10.3390/s19010025 | DOI Listing |
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