Centre county Pennsylvania, USA |
Great observation, there is a (significant) difference between accuracy and reliability. Errors that are small (sub meter) are accuracy problems, but 18 foot jumps are reliability problems. I recall similar problems when WAAS was coming on-line, in fact I think I recall that WAAS didn't work at all on certain days of the week in some Ag Receivers, including those from Deere.
Now that DOT has, or is, upgrading beacon DGPS service in most areas of US, beacon DGPS service is (or soon will be) a very good backup for WAAS DGPS service over almost all of US. We have decided that the next high quality Ag DGPS receiver we purchase will have both WAAS and Beacon DGPS capability, that seems to be a low cost way to get enhanced DGPS reliability, wherever we need it. Hopefully, we will never need backup for GPS service.
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