2 ms·
Interesting. I wonder if the altitude readings were WAAS augmented, or if this is a case where theory doesn't translate in to reality.
by dholowiski 15y ago
Interesting. I wonder if the altitude readings were WAAS augmented, or if this is a case where theory doesn't translate in to reality.
- runjake 15y agoAh. You may be right, there. WAAS is enabled on my GPS (a Garmin 60CSx). Link for bystanders: http://en.wikipedia.org/wiki/Waas http://en.wikipedia.org/wiki/Waas WAAS uses a network of ground-based reference stations, in North America and Hawaii, to measure small variations in the GPS satellites' signals in the western hemisphere. Measurements from the reference stations are routed to master stations, which queue the received Deviation Correction (DC) and send the correction messages to geostationary WAAS satellites in a timely manner (every 5 seconds or better). Those satellites broadcast the correction messages back to Earth, where WAAS-enabled GPS receivers use the corrections while computing their positions to improve [3D] accuracy.
- toomuchtodo 15y agoAnd if you need even higher resolution (centimeter resolution), use use NOAA CORS sites (either with post-processing, or real time with their experimental datafeed) http://geodesy.noaa.gov/CORS/data.shtml http://geodesy.noaa.gov/CORS/data.shtml http://beta.ngs.noaa.gov/CORS/NGSRealtimeGNSS/ http://beta.ngs.noaa.gov/CORS/NGSRealtimeGNSS/