inconsistent frame rate and wrong time to value assignment

[ga58lar]

Firstly, thank you for the OSS ROS 2 driver!

Describe the bug
I am using your PwrPak7D-E2 receiver with the latest ROS 2 humble driver on a normal vehicle. I attached the config at the end of the issue.
A closer look at the data revealed that the ROS 2 messages do not arrive at a constant data rate. This can be seen, for example, with BESTPOS, BESTGNSSPOS, or BESTVEL. In addition to the inconsistent frequency, there also appears to be an incorrect assignment of the values to the time stamps. If the vehicle direction and speed remain constant, there are jumps when plotting the values over time. However, if you plot BESTPOS with lat/lon as a 2D plot, for example, you will see a constant distribution of the measurement points. This indicates that the position data is recorded correctly, but is time-stamped and sent with a delay/inconsistently. You can see the behavior in the attached diagrams. I have also included a short ros2bag with BESTPOS data.

To Reproduce
Steps to reproduce the behavior:

1. ros2 launch novatel_oem7_driver oem7_net.launch

Expected behavior
Consistent data rates and outputs of the ROS2 topics.

Screenshots

Environment:

• OS: Dockerized - Ubuntu 22.04
• ROS 2 Humble
• novatel_oem7_driver/humble: d82103e
• Receiver: PwrPak7D-E2 with dual antenna setup
• Firmware: 7.09.02

Attachments
custom_init_commands.yaml
novatel_bag.zip

[novatel-applications-engineering]

Hi @ga58lar
We would like to gain more understanding about your network and the connections used, can you please submit a case through NovAtel's support website, in order to provide us with more details?
Please mention this GitHub issue in the case.