How do you troubleshoot satellite communication systems for signal loss?

An example I have seen in Thuraya and Inmarsat User terminals is checking the signal strength using the terminal first. Since a typical user may need a signal analyzer, the next best step is analyzing using another user terminal. Then, we can clear off any Terminal-related possible issues.

If you are looking for quick troubleshooting at a remote end, a good reference to check is the receive power and/or the EsN0 or C/N. Depending on your antenna setup, the received levels can differ. It is always a good idea to record baseline values during commissioning. This way, it is possible to some form of first level troubleshooting without a spectrum analyser.

From an example I was following together with our Customer Support Team, We first access the satellite satellite receiver or modem with the help of monitoring team. Signal strength should ideally be at its highest level, and signal quality should be around 99.9% of availability or around the percentage given in the link budget. If this is not possible, we check another terminal user under the same conditions.

Check for Physical Obstructions: Ensure there are no physical obstructions such as trees, buildings, or structures blocking the line of sight between the antenna and the satellite. Even small obstacles can cause signal loss.

Revisiting the antenna’s 3dB and 10dB measurement, as well as regularly performing G/T calculations using the Y-factor, is essential to ensure optimal signals reception.

This procedure is call peak and pol. Here you can use the provider to assist you with the cross pol and also getting a compression point on the BUC or Amplifier.

Depending on your frequency band and satellite used, scan a bit further past the peak. There are scenarios where the first measured peak signal is a sidelobe.

The cable loss is also of utter importance. Measuring the cable loss can point you to the issue if you have a signal loss. This loss might involve bad connector, issue with fiber not connected properly or even other parts that are in your measurement.

Please ensure that you regularly monitor the 1dB compression point of the HPA. It is a good practice to perform and record this value during preventive maintenance activities. Be particularly vigilant about potential degradation in tube performance, especially with TWTA type HPAs.

To identify the root cause of the interference sources, first observe and understand the surrounding by looking around the satellite and based on the location of the place whether it often raining, is facing a lot clusters of buildings, a lot birds and bats flying pass it etc using direction finder to detect the position where strong frequency are detected.

I deal with this kind of requests on my day to day work. Optimizing satellite communication systems as well as estimating performances and reliability is one of the main tasks linked to Problem-solving strategic skills. This means considering all the link specifications from the HUB to the Remote including Ground segment losses. Investigating the computed study and offering a better performances by either providing more Mbps or better availability or Less Bandwidth occupation for the same throughputs.

One thing more... I will check condition of Waveguide.... Is it in good condition or not.... A single crack in it may lost the signal while uplinking.... Secondly... BiasT power.... By checking BiasT power we can troubleshoot our signal loss issue