Synchronization of the Probes of a Distributed Instrument for Real-Time Ethernet Networks

This work deals with distributed, multi-probe, instrument for performance analysis of Real-Time Ethernet (RTE) network Particularly, the work is focused on synchronization techniques for distributed measurements. In fact, the accuracy of results (typically jitter and delay) strictly depends on synchronization among distributed probes that sample data. Three synchronization techniques have been implemented and experimental results are reported. Synchronization by means of an external dedicated l-PPS signal gives the best results but requires a more complicated instrument structure. On the other hand, a network-oriented synchronization, such as IEEE 1588 FTP or PCTP (PROFINET 10), can simplify time distribution keeping accuracy well below 1 mus.

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