GPS Accuracy in Collector

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10-19-2020 07:41 AM
SLouq
by MVP Regular Contributor
MVP Regular Contributor

I may already know the answer to this question but I thought I would ask the board just to confirm or reaffirm what I think.

I have a GNSS receiver which I want to use to collect elevation readings out in the field. Everything is set up and working correctly but if you have worked in Collector and used a GNSS receiver to collect data then you may have notice in the top right corner above your web map there is text that tells you when your GPS receiver is connected and what accuracy you are getting.

My question is does this GPS accuracy reading tell you how far off you are standing from your actual position or how far off your elevation reading is from the actual elevation?

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2 Replies
Jean-YvesLauture
New Contributor III

Hello Scott, 

Please note that any ESTIMATED accuracy reported by any GNSS receiver remains an estimated accuracy. It is not the absolute truth and should be an indication of how well the receiver is more or less behaving in a specific environment. 
Different manufacturers will handle estimated accuracies in different ways in their algorithms. Therefore, I suggest you take your receiver on a survey monument, first in clear view of the sky, and compare estimated accuracy vs true location. If you can repeat the same in “non-ideal” conditions (light canopy, or light or moderate urban canyon) then you’ll have a clear picture of how the receiver’s estimated accuracy compares to the reality. 

Last, also note that, as a rule of thumb (and this is valid for any GNSS receiver), vertical accuracy is usually 1 to 3 times less the horizontal accuracy. For example, if you are getting 2cm accuracy horizontally, your vertical might be anywhere from 2 to 6cm. 

Best of luck,

JY 

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SLouq
by MVP Regular Contributor
MVP Regular Contributor

Thanks for the reply JY!