Synchronet – an innovative system

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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