SEPTENTRIO PolaRx5S, User Manual

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4.4. HOW TO ENABLE THE NTP SERVER
longer one, the overall signal delay would be increased by say, 20 ns. I f the Delay value is
left unchanged, the PPS pulse will arrive 20 ns too late. To re-synchronize the PPS pulse, the
Delay should be increased by 20 ns. The delay can be con
fi gured with values between -1 ms
and +1 ms.
By default, PPS pulses are aligned with the satellite time system (TimeSys) as shown in
the
Time Scale fi eld. PPS signals can alternatively be aligned with UTC, local receiver time
(RxClock) or GLONASS time.
When Time Scale is set to anything other than RxClock, the accuracy of the time of the
PPS pulse depends on the age of the last PVT computation. During PVT outages, the PPS
generation time, which is extrapolated from the last available PVT information, may start
to drift. To avoid large biases, the receiver stops outputting the PPS pulse when the last
available PVT is older than the speci
fi ed MaxSyncAge . The MaxSyncAge is ignored when
TimeScale is set to RxClock.
Step 3: Click on ‘Ok’ to apply settings
The new con fi guration can also be saved as the boot con fi guration by clicking ’ Save ’ in the
pop-up.
4.4 How to enable the NTP server
NTP (Network Time Protocol) is an I nternet protocol for clock synchronization between
computer systems over data networks. I t is intended for synchronizing participating
computers to within a few milliseconds of UTC. The NTP server functionality on the PolaRx5S
can be con
fi gured as shown in Figure 4-15. When enabled, the NTP server accepts UDP
time-stamp requests on port number 123.
Figure 4-15: Enabling the NTP server
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