Synchronize Ettus X310 SDR with Live-Sky


We have built our own Skydel simulator that is paired with an Ettus X310 SDR running Skydel 23.8.0. We wish to perform simulations that are synchronized to the Live-Sky GNSS signals overhead but are unsure about what additional hardware is required. Our Ettus X310 SDR is currently paired with the Ettus 5-Volt Active GPS antenna and the internal GPSDO but looking through the Skydel User Manual it appears as if a GPS Timing Receiver should be added to the system to support this request. Do we only need a GPS timing receiver to synchronize Skydel to the Live-Sky GNSS signals? We are considering the addition of the ublox ZED-F9T module (pictured below). If we used this timing receiver would we only have to feed the Time Pulse 1 output of the timing receiver into the PPS TRIG IN port of the Ettus X310 SDR (also pictured below)?


Hi @grote ,

You would need to connect the Time Pulse 1 output of the timing receiver into the PPS TRIG IN port of the Ettus X310 SDR as you said, as well as connect the ZED-F9T module via a serial connection (USB) to the Skydel simulator.

You would then go to Skydel’s Preferences and connect the timing receiver in the Sync tab:

You should then see your receiver with the correct time in the Start Time tab (note my receiver currently doesn’t have a PVT in the following screenshot):

Hope that helped,

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Hey Mathieu,

Thanks for confirming our suspicion, we thought at first that we would need to purchase an OctoClock-G to support this request but instead we will try out the new Ublox timing receiver.

Thanks again,

Hi @grote,

No problem, I just forgot to mention, Skydel expects NMEA data to get the time from the receiver.
The RMC and GGA sentences need to be enabled on the receiver in order for Skydel to get the time.

Any device that can be connected to via a serial port and provides the RMC / GGA NMEA sentences should work as a timing receiver with Skydel.


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