SynchroNet is a GNSS based time and frequency transfer system that allows
to exploit high accuracy synchronization of accurate clocks
Implementation and
Test Results
The main issue is the validation of
SynchroNet core synchronization
algorithms in their many components:
ionospheric and tropospheric
models implementation, code (i.e.
pseudorange: Code and Phase)
based CommonView, phase based
CommonView (L1 and L2), clock stability
characterization by mean of CV and comparison to direct synchronization
in lab (PPS biases analysis).
IGS was selected as a test bench for
algorithms validation thanks to the
wide set of products available allowing
a significant statistical analysis.
Here after are presented some
results of both validation test results
and of performance assessment
of SynchroNet algorithms.
SynchroNet is at its v1.0 verification
phase but its kernel is already running
as core service for the Galileo Test
Range (GTR), an advanced research
facility for the experimentation and
analysis of the Galileo Signal, for testing
and certification of user terminals and support services for the development
of application services. In the frame
of this project, SynchroNet is used for
synchronization of pseudo satellites
OCXO driven Rubidium clocks used for
ranging measurements with a requirement
of 5ns ( ~1.5m) 1σ accuracy. In this
context the main reference time (MRT0)
is a free running Active Hydrogen
Maser atomic clock while Control center
features are customized and integrated in
the Control centre facility of the GTR.
Conclusions SynchroNet is a GNSS based time
and frequency transfer System that
allows to exploit high accuracy
(nanoseconds and picosends level) synchronization of accurate clocks
over large baselines by wrapping the
synchronization service in a robust
and flexible infrastructure providing
security and scalability features.
Through separated and successful
validation campaigns using IGS
network and in a full deployed
system (the GALILEO Test
Range), SynchroNet has proven its
customizability and performances.
Currently SynchroNet is going
through a further design and research
phase in order to consolidate and
expands its features at infrastructure
level to match critical systems
requirements in order to become a
high performance synchronization
solution for every applicative domain.
Bibliography
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Island of Ponza (Italy)
Monica Gotta
Responsible for Thales
Alenia Space Italia, of
the System Engineering
activities as part of System Integration and
Verification Contract of Galileo Phase C/D/E1.
Enrico Varriale
System Simulation Engineer for the Navigation and
Integrated Communication
Business Unit.
Daniele Cretoni
System Engineer in the
Department of Navigation
and Integrated Comms B.U.
of Thales Alenia Space Italia.
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