Question about Fix and Float

I have a pair of Reach RS2 units. I set one up as the Base and one as the Rover. When using the Survey feature in the ReachView app today I set the Base up in a nice clear area and many of the points that I was gathering were also in a clear area. The status of most all of my points was Fix while collecting, but in a few cases I had to go into a wooded area and the status changed to Float. In my past reading about the Float status it is my understanding that all the points gathered while in Float have the correct relationship between themselves but may not be accurately georeferenced.

I have two questions:
1: Do all the points, regardless of whether or not collected in Fix or Float have the correct geometric relation to each other?
2: If not, I keep reading about this post processing that somehow will bring the incorrect points into the correct relationship. Is this a straight forward process and is there a good guide that explains how to achieve this?

Thank you in advance for any help or links you can provide.

Frank

Nope, float is more or less to be considered as the Single Solution, just with correction. Float can be meters off, if SNR is bad enough, and baseline long enough.

Post-Processing will be able to correct some float-solutions, but it is no miracle. Usually, when you encounter floats it is because of bad SNR. Some tweaks can made during the post-processing, but again, no miracle cure.
You can read more here: https://docs.emlid.com/reachrs2/common/tutorials/gps-post-processing/

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Christian,

Thanks for the quick response. What is SNR? Also, is it then incorrect that if I go out and collect 6 points all in float that they are not geometrically correctly related? Sorry to have such basic questions but this is new to me.

Correct, they are not. Only in a Fixed solution will they be aligned, relative to the base, within the limitation of the hardware and the baseline-length.

SNR is Signal To Noise Ratio, basically the quality of the signal the receiver receives.

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Hi Frank,

I believe I can only add to Christian’s answer that you can also check Status guide to learn more about SNR and solution statuses.

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