Can groops do PPP using Beidou constellation?

[FFFFFG-IGG]

Description

Hello developers, I'd like to do PPP with Beidou constellation, but the results are not good. Here are results of fix ambiguity and float ambiguity in ppp processing(note that doy: 2020 002 station:graz products:wum):

Figure 1 fix ambiguity Figure 2 float ambituity Note that only band L2 and L6 are used, and I there aren't any problem when I do ppp with GPS or Galileo constellation. By the way, I'v met the same problem when I do ppp with Glonass constellation as Beidou. Could you give me some suggestion about that? Regards, I'm looking forward to your reply!

GROOPS version

main (latest commit)

Operating systems

• [ ] Linux
• [X] Windows
• [ ] macOS
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Log output

No response

[Waley04]

Hi @FFFFFG-IGG,

GROOPS Developers Can Explain Better.

I tried a PPP test with the following parameters:

== DOY : 002 in 2020 == Products : WUM0MGXRAP * == Station : jfng and graz == System : BDS only == Freq : B1 and B3

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FIXED SOLUTION

1-JFNG Station ---

2-GRAZ Station ---

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FLOAT SOLUTION

1-JFNG Station ---

2-GRAZ Station ---

Best wishes,

Waley.

########################################################### Disclaimer: I just know how to deploy PPP experiments in this software. GROOPS developers can explain the quality of the solution. ###########################################################

[zhedumi]

Hi,

Yes using BeiDou in PPP is possible but I should also note that we currently have a development branch for BeiDou with some updates, improvements and fixes for future releases.

To the results of yours it is interesting that in your results the float solution seems to be doing better than the fixed solution which is definitly not what I would expect. Might I know what parametrization, models you both used to get these results and what observations, satellite products, clock-products, phase biases etc. you used?

On a sidenote GLONASS always gives worse results since the observations/orbits are usually worse in comparison to other GNSS. Check Strasser 2022 Chapter 8.2.

Best regards, Patrick