GNSS RTK Accuracy
Quote from MightyMoe on October 29, 2024, 5:53 amWe tend to see the recommended accuracy that Trimble states. 8mm +1ppm. This is only for wide open sky. We're lucky to have monumented and extensively surveyed control set by DOT, it gives us a very good way to check our RTK. Normally anything over a cm gets another location. If it shows .04', shoot it again. And this is standing over the point with a rod (no bipod-no fixed height rod); base on a random control point and running along the highway shooting 30-60 control points. Typically .01'-.02' horizontally, .02'-.03' vertically. No time spent on the points, a 15-45 second shot and move on to the next.
When it's tough sky conditions I trust nothing the unit is displaying. If it's over the .02h, .03v readout anything might be happening. I will say the newish Trimble units will tend to not allow a bad fixed shot. Under a big yellow pine might require an instrument. If you can get two fixes, separated by a few minutes and they match, with different HI's we've never seen those be off. Also, with the large number of satellites, some can be turned off and on to help with multi-path. But anymore we normally let it work itself out in canopy and don't fool with satellites.
We tend to see the recommended accuracy that Trimble states. 8mm +1ppm. This is only for wide open sky. We're lucky to have monumented and extensively surveyed control set by DOT, it gives us a very good way to check our RTK. Normally anything over a cm gets another location. If it shows .04', shoot it again. And this is standing over the point with a rod (no bipod-no fixed height rod); base on a random control point and running along the highway shooting 30-60 control points. Typically .01'-.02' horizontally, .02'-.03' vertically. No time spent on the points, a 15-45 second shot and move on to the next.
When it's tough sky conditions I trust nothing the unit is displaying. If it's over the .02h, .03v readout anything might be happening. I will say the newish Trimble units will tend to not allow a bad fixed shot. Under a big yellow pine might require an instrument. If you can get two fixes, separated by a few minutes and they match, with different HI's we've never seen those be off. Also, with the large number of satellites, some can be turned off and on to help with multi-path. But anymore we normally let it work itself out in canopy and don't fool with satellites.
Quote from OleManRiver on October 29, 2024, 10:02 am@field-dog I have no idea how that works in the Carlson data collector really. I know assume that you can do that with the precisions and that fancy statistical average of points it would seem. When I helped my friend he was running the data collector as I did have my eye glasses on as I was just there to help him on what to look out for multipath wise and checking against some points I had derived with static .
@field-dog I have no idea how that works in the Carlson data collector really. I know assume that you can do that with the precisions and that fancy statistical average of points it would seem. When I helped my friend he was running the data collector as I did have my eye glasses on as I was just there to help him on what to look out for multipath wise and checking against some points I had derived with static .