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GPS Network Time Server
TECHNICAL: 0118 965 6000
Product Description
General
The GPS Network Time Server meets the precise synchronization and syntonization
requirements of local and remote users.
The GPS Network Time Server offers highly accurate and stable frequency sources
synchronized and slaved on the reception of signals transmitted by the GPS satellite
constellation.
The clock operates on a stand-alone basis, in a predefined setting. This configuration can be
modified by the user, via the remote control interface.
The clock integrates a GPS receiver used to deliver, at user level, the time/frequency
reference broadcast by the GPS system. It autonomously uses the integrity aspects of this
system (TRAIM); i. e. it automatically rejects the signals transmitted by satellites considered
as faulty, which might impair the clock’s performance.
The time reference thus obtained is processed by high performance algorithms, which control
the internal frequency pilot of the unit. The system is used to distribute frequency and time
signals (1-pps second signal) locally, and time stamp and synchronization messages remotely,
via Ethernet network under IP or by IRIG signal over amplitude coded on symmetrical pair.
Distribution under IP is performed using the NTP protocol for which the GPS Network Time
Server is a primary timeserver.
In case of GPS reception loss, the clock maintains the time and frequency distribution from
its internal pilot. Also, learning of the frequency pilot behaviour (effects resulting from
ageing and temperature variations, in the presence of the GPS reference), it is used to
improve the time and frequency distribution performance when the GPS is lost.
Most functions of the GPS Network Time Server are software controlled. At start-up, the unit
runs self-tests of its hardware resources, it checks that its internal pilot is stabilized and
makes a first coarse adjustment of the distributed frequency. After half an hour of operation,
the frequency accuracy is of 1.10-9 and the time accuracy is less than 1 s relative to
UTC(GPS) time.
As a timeserver on IP protocol, the GPS Network Time Server includes a DHCP and a
BOOTP client. Those clients automatically set to the configuration of the GPS Network Time
Server as it is connected to server configured IP network. Through the remote control link,
the GPSNTSTP external software enables the configuration of an address mask for
broadcasting to specified subnets.
