GNSS Sky Block Experiment

• phone or GNSS receiver
• open-sky outdoor area
• location with partial sky blockage such as near tall buildings, under a roof edge, or beside a high wall
• notes or screenshots
• optional GNSS app or status page that shows satellite count, reported accuracy, and fix stability

1. Stand in an open area with a wide view of the sky and let the receiver stabilize.
2. Record the reported accuracy, visible satellite count if available, position stability, and time-to-fix or convergence time.
3. Move to a place with a blocked view of the sky and record the same values again after waiting for the receiver to settle.
4. If possible, repeat the comparison more than once and keep the same device, app, and observation duration for both locations.

This visual shows the core geometry the experiment is testing before the real-world observation is made.

• Open sky usually gives a faster fix, tighter reported accuracy, and a steadier position.
• Obstructed sky often produces slower convergence, a larger uncertainty circle, more position jumping, or fewer reported satellites.
• The effect depends on how much of the overhead satellite view is blocked and how much reflected signal contamination is introduced nearby.
• If your receiver or app exposes satellite count or DOP-style quality values, those should usually look worse in the blocked-sky position.

That pattern fits a satellite-based ranging system that needs multiple lines of sight across the sky, not a simple local-tower story. By itself this is still an observational field test rather than a full proof, so the cleanest approach is to repeat it carefully and compare multiple runs.

Open a tag to see related tools, debunks, and experiments grouped by the same topic.