Cause of intermittent under-canopy RTK interruptions

Determine whether canopy obstruction, multipath, cellular connectivity, correction-stream availability, or a combination of these factors causes the intermittent RTK-fixed positioning failures observed during under-canopy UAV flights.

Background

The ForVis dataset uses RTK-fixed GNSS as a trajectory reference for meadow and above-canopy flights, but reliable RTK-fixed solutions were intermittent beneath the forest canopy. The paper identifies several plausible causes, including canopy obstruction, multipath, cellular connectivity, and correction-stream availability, but does not establish which factor or combination of factors is responsible. Resolving this uncertainty would clarify the reliability limits of RTK-based references for under-canopy UAV datasets and improve the interpretation of GNSS measurements collected in forests.

References

The source of these interruptions could not be isolated: canopy obstruction and multipath can degrade satellite measurements, while cellular connectivity and correction-stream availability can also affect RTK operation.

— ForVis: An In-Field Dataset and Benchmark for VIO Using Under-Canopy UAV Flights in Forests  (2609.35482 - Kiani et al., 28 Sep 2026) in Appendix, subsection “GNSS/RTK Reference Setup”