Min ratio to fix ambiguity and False Fix

[Doppler_Uav]

Hi all,

I have a static measurement of a point with a RS2. The point height is 20.51

I post-processed with RTKlib QT using “static” and “solution for static mode: All”.

With a “Min ratio to fix ambiguity” value of 3 for I get some Fixed values that have an error of about 20cm:

With a “Min ratio to fix ambiguity” value of 4.5 for I get ALL values between 20.48 and 20.51, very good result:

From this I can say that using Min ratio of 3, I get some false fixes and using a value of 4.5 I do not get any false fixes.
in this case I knew the real value of the height and I can tell when there is a false fix, but for example in a UAV kinematic log, I don’t know the real values so I can’t realize if there is a false fix.

How can I interpret that? Is it better to use 4.5 Ratio for all cases? Can someone explain a bit more about Min Ratio? I read the RTKlib manual but still is not clear to me, besides that you should never use less than 3.

Thanks.

[svetlana.nikolenko]

Hi @Doppler_Uav,

Do you use another Reach RS2 as a base? Would you mind sharing the logs with me? You can send it in PM if it contains sensitive info.

[Doppler_Uav]

Hi @svetlana.nikolenko,

In this case I used a Cors station as a base. I was trying different options for post-processing and different occupation times. Baseline was about 53km.

The rover was static in the same point.

I’ll send you the files in PM.

[svetlana.nikolenko]

Just want to post an update here that I’ve received the files. I’ll get back to this thread once there is any news.