Why is Quantum flashing red?

When Quantum is flashing RED, a critical problem might have arisen that needs attention and a solution. This article explores some common issues that may trigger Quantum to flash red. Before going into detail on the different scenarios and possible root causes, some general advice is worth noting:
  • Check the active notifications tab. A red numbered icon highlights the active count of messages requiring attention. Often the message in the notification will explain the error and may point to a solution.

Quantum notification tab

  • After every round of troubleshooting (even if you can not locate the issue), restart Quantum and recheck.
  • When problems persist, contact the VERIPOS Helpdesk for detailed guidance and analysis.
Keeping the above in mind, we can now split the problem up into the following likely scenarios:

Scenario 1: No display tiles are populated, and there is a red flashing border

Quantum red and unpopulated
Verify that the Ethernet connectivity from the system to the Quantum PC exists. If there is no connection issue, restart Quantum and ensure the correct demodulator settings are in the software. Check and confirm the version of Quantum is compatible with the VERIPOS receiver. 

Scenario 2: Quantum is flashing red with some display tiles populated

Quantum partially populated flashing red

Partially populated displays give a general indication that the IP connectivity is good.

If no GNSS satellites are present within the polar plot, then check the GNSS status on the VERIPOS receiver (for the LD8 units, the GNSS LED should constantly flash green). Check the L-band signal strength if the VERIPOS receiver uses a combined antenna. If both GNSS and L-band signals are absent, there is a strong possibility one of the following problems is present:

  • The antenna has no LNA power supply (controlled by receiver configuration)
  • There is a loose RF connector
  • The RF coaxial cable or RF pigtails or connectors is defective
If the VERIPOS receiver indicates a problem, then the antenna connections and coaxial cables will need to be tested.

Scenario 3: Quantum is flashing red with display tiles populated

Quantum populated and flashing red
Again we can note the IP connectivity is good, and we can also note that GNSS tracking is operational. In this case, a slow or non-convergence of the PPP solution may be the underlying cause of the red warning.

Typical reasons for convergence issues include:
  • Insufficient GNSS satellites due to blockage, coaxial cable or antenna faults.
  • Poor/intermittent reception of the VERIPOS L-band signal.
  • High levels of GNSS multipath
The above example shows a high percentage of GNSS satellites in red within the polar plot. In contrast, several GNSS satellites (green) are present in half of the polar plot, suggesting an indication of potential blockage (masking).
If the GNSS missing satellites spread across 360 degrees, it could also be due to an interference source. In addition, similar behaviour might occur in a rich multipath environment.

Also, check the L-band signal strength. If the signal strength is unstable, then PPP convergence may be continually interrupted, so unable to converge. Use the time series graphics to confirm that the L-band signal is continuously healthy (as shown in the image above).