RT PPP example with SSR stops at epoch 2 – YAML ready-to-run?

[jgarmen-git]

Dear Ginan Team,

I have been testing all the YAML examples included in Ginan v3.1.0 without any modifications. I am not sure whether the provided YAML files are fully ready-to-run for a user, or if additional setup/configuration is needed. Most of the examples work correctly. However, all examples related to real-time processing using SSR fail when observations are processed. The record_streams.yaml example works fine, so NTRIP access and data download seem OK.

The issue appears with rt_ppp_example.yaml (and similarly with rt_rtk_example.yaml). Processing starts normally, but when the first epoch with synchronised receiver observations is reached, processing stops with the following messages:
Warning: No sat pos found for G01
double free or corruption (out)

In practice, epoch 1 contains no synchronised receiver data, while epoch 2 is the first epoch where observations from all receivers are available, and this is where the failure occurs.

This happens even though:

• RTCM observations are received correctly
• No connection errors were reported for SSR streams
• Receivers become synchronised before the error occurs

To rule out network or latency issues affecting SSR reception, I tested the same configuration on different computers, locations and internet connections, and observed the same behaviour.

Compilation details:

• GINAN branch: main
• GINAN version: untagged-3162f8796e5ae38581942e760cf504870dea5eb1
• Operating system: Linux (Debian 12)
• Compiler version: GNU 12.2.0
• Boost version: 1.74.0
• Eigen version: 3.4.0
• Mongocxx version: 3.7.0

Is this a known limitation or configuration issue with RT PPP + SSR?
Do I need to modify the original YAML configuration for it to work correctly?

Thanks in advance.

[smcclusky]

Could you please try downloading Ginan v4 and let us know if you are still seeing the same problem?

[jgarmen-git]

I am going to try it

[jgarmen-git]

Dear Simon McClusky,

I have installed Ginan v4 following the option of compiling from source.

I have used rt_ppp_example.yaml as provided, only changing SSRA00CNE0 to SSRA00BKG0. When running this YAML, the previous issue observed in Ginan v3.1.0, where the processing would stop at epoch 2, seems to be resolved. The processing now proceeds smoothly, with epochs being processed successively. I am attaching an example POS file ALIC_rt_ppp_example__202602600.POS.zip and part of the terminal output rt_ppp_example_output.txt.zip for verification, to check whether this YAML execution behaves as expected.

Additionally, I have run rt_rtk_example.yaml as provided, without any modifications. On screen, warnings such as Apriori for NEWE is 2430 m from SPP estimate appear, and the minimum discrepancy I have seen is around 200 m. I am unsure whether this behavior is expected with the default YAML configuration, or if it indicates an issue with my execution.

Thank you for your guidance.

Best regards