Measuring propagation delay over a coded serial communication channel using FPGAs

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 626; pp. S169 - S172
• Main Authors: Jansweijer, P.P.M., Peek, H.Z.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 11.01.2011
• Subjects: 8B/10B; 8B10B; Channels; Computer networks; Delay; Detectors; Ethernet; FPGA; IEEE 1588; Intervals; Network timing; Neutrino telescope; Propagation delay; Serials; Spectrometers; Spreads; Timing; Timing calibration; Timing calibration; IEEE 1588; FPGA; Ethernet; 8B/10B; Network timing; 8B10B; Neutrino telescope; Timing; Propagation delay
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2010.04.126

Measurement and control applications are increasingly using distributed system technologies. In such applications, which may be spread over large distances, it is often necessary to synchronize system timing and know with great precision the time offsets between parts of the system. Measuring the propagation delay over a coded serial communication channel using serializer/deserializer (SerDes) functionality in FPGAs is described. The propagation delay between transmitter and receiver is measured with a resolution of a single unit interval (i.e. a serial link running at 3.125 Gbps provides a 320 ps resolution). The technique has been demonstrated to work over 100 km fibre to verify the feasibility for application in the future KM3NeT telescope.