Satellite number less than 10

Hello guys. Any buddy has experienced in drone processing, why satellite number in event pos file is less than 10. I have checked drone observation data, and I found there are more than 20 satellites.
I use K1 swan mapping from HEQ. Thank you

Hello !

The number of satellites in view at the rover can differ from the number of satellites used in the baseline processing, with the characteristics that the first is always greater or equal to the second.

The baseline processing uses the common set of satellites in view at the rover and at the base. Another set of sats can be excluded from the process depending on the elevation and SNR masks setup.

Having less than 10 sats in the pos file can be caused by the base tracking GPS only for example, making Glonass, Galileo and Beidou observations at the rover useless.

Could you drag n drop both RINEX files from base and rover in the Emlid Studio window and share the graphics here ?

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Left is rinex from CORS, and right one is from K1 Swan mapping.
I checked all satellites sxcept IRNSS

And I got only 5 to 8 satellites in pos file.

Hi @dicky,

The reason for this is that satellite observations from K1 Swan have very poor quality. Noisy satellites with multiple cycle slips (they’re shown as red bars) are excluded while post-processing. Hence, you see fewer satellites in the resulting pos file.

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Sorry, how is it could be multipath on 120 meters height? PPK antenna position on the top, and there is no thing cover it.

The placement of the M2 module next to especially power lines in the uav can give this impact.
Can you post some pictures of the installation?

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Maybe you can compare yours with this file ,this is also come from PPK drone system (Teokit) and this is your raw data should looks like

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Hi @dicky,

It depends on your UAV setup. As I see, you’re using a third-party receiver in it, so I believe that its manufacturer or supplier can tell you more about this configuration.

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When I set min ratio to fix ambiguity into 1, I got fix all. My question is why we should use 3 for value? I have to told to my leader that K1 cycle slip is too much. My leader want to know why we should use min AR in 3.

I always use 3, but the K1 seller asking me to use 1 for min AR value.

Hi @dicky,

The higher this ratio is, the higher the confidence that the best solution is the correct solution. If too low a value is chosen, your points even with FIX solutions may be shifted.

I have new problem, good signal with no cycle slips, but I got low number satellites and I got 24 points float


Hi @dicky,

Please send us your raw data logs to support@emlid.com. I’ll post-process them to see what might be the reason for this.

So sorry I have got fix solution for all my float data. I checked the AR validation for glonnas fix dan hold. Thank you @kirill.pavlyuchuk for your attention.

But I got other strange screenshot from my friend. He worked in RTK mode. I just realized it. Even though he sent a picture this afternoon

Hi @dicky,

Please suggest him to update the app to the latest 8.9 version and the receiver to 30.1 firmware. Let him check if the issue persists after this.

If it does, I’d suggest contacting us at support@emlid.com for further troubleshooting.