High-Precision, High-Accuracy Timekeeping in Distributed Survey Systems

Authors

  • B. R. Calder
  • R. T. Brennan
  • J. Marcus
  • C. Malzone
  • P. Canter

Abstract

Accurate and precise timekeeping between computers in a distributed survey system is essential to ensure adequate data quality, especially with Multibeam Echosounders (MBES) which can otherwise suffer from significant motion artefacts. We show that clock synchronisation on the order of 100-150ns (rms) is readily achievable in a modern MBES-based survey system utilising an Ethernet-based time synchronisation mechanism and some custom timekeeping software. We also show that improving the timekeeping eliminates motion artefacts in the observed bathymetry, and simplifies the patch-test procedure.

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Published

2008-01-01

How to Cite

Calder, B. R., Brennan, R. T., Marcus, J., Malzone, C., & Canter, P. (2008). High-Precision, High-Accuracy Timekeeping in Distributed Survey Systems. The International Hydrographic Review, 9(1). Retrieved from https://journals.lib.unb.ca/index.php/ihr/article/view/20801

Issue

Volume 9, Number 1 (2008)

Section

Articles

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 Anders, F.J. and Byrnes, M.R.(1991). “Accuracy of shoreline change rates as determined from maps and aerial photographs”, Shore and Beach, 59, pp. 17-26.

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Foley, J.D., van Dam, A., Feiner, S. K. and Hughes, J.F. (1990), Computer Graphics – Principles and Practice, 2nd ed., Addison-Wesley, Reading, MA.

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Smith, A. (1988). Colour photomapping. Report NRC-01-512. National Research Centre. Ottawa, Canada.

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