Three satellites at the top send signals straight down to a drone over open ground, and its position estimate, shown as a dashed ring, sits on the drone. The drone then flies close to a tall building. Now one satellite's signal also bounces off the building wall before reaching the drone. With both direct and reflected signals, the position estimate drifts and jumps away from where the drone really is, while the GNSS status badge still shows OK: false confidence. When the drone flies back away from the building, the reflection stops and the estimate rejoins the drone. Offsets are schematic.
