High Accuracy Time of Flight Measurement Using Digital Signal Processing Techniques for Subsea Applications
Muhammad Ashraf, Hamza Qayyum
DOI: 10.4236/jsip.2011.24047   PDF    HTML     9,621 Downloads   15,371 Views   Citations


The techniques widely used in ultrasonic measurements are based on the determination of the time of flight (T.o.F). A short train of waves is transmitted and same transducer is used for reception of the reflected signal for the pulse-echo measurement applications. The amplitude of the received waveform is an envelope which starts from zero reaches to a peak and then dies out. The echoes are mostly detected by simple threshold crossing technique, which is also cause of error. In this paper digital signal processing is used to calculate the time delay in reception i.e. T.o.F, for which a maximum similarity between the reference and the delayed echo signals is obtained. To observe the effect of phase uncertainties and frequency shifts (Doppler), this processing is carried out, both directly on the actual wave shape and after extracting the envelopes of the reference and delayed echo signals. Several digital signal processing algorithms are considered and the effects of different factors such as sampling rate, resolution of digitization and S/N ratio are analyzed. Result show accuracy, computing time and cost for different techniques.

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Ashraf, M. and Qayyum, H. (2011) High Accuracy Time of Flight Measurement Using Digital Signal Processing Techniques for Subsea Applications. Journal of Signal and Information Processing, 2, 330-335. doi: 10.4236/jsip.2011.24047.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] D. G. Tucker and B. K. Gazy, “Applied Underwater Acoustics,” Pergmon Press Ltd., Oxford, 1966.
[2] J. L. Sutton, “Under Water Acoustic Imaging,” Proceedings of the IEEE, Vol. 67, No. 4, 1979, pp. 554-566. doi:10.1109/PROC.1979.11283
[3] D. Marioli, C. Narduzzi, C. Offelli, D. Petri, E. Sardini, and A. Taroni, “Digital Time of Flight Measurement for Ultrasonic Sensors,” IEEE Transactions on Instrumentation and Measurement, Vol. 41. No. 1, 1992, pp. 93-97. doi:10.1109/19.126639
[4] V. A. Krasilnikov, “Sound and Ultrasound Waves,” 3rd Edition, Washington, 1963, p. 167.
[5] C. E. Tibbs and G. G. Johnstone, “Frequency Modulation Engineering,” Chapman and Hall Ltd., London, Chap. 2, 1956.
[6] M. Parrilla, J. J. Anaya and C. Fritsch, “Digital Signal Processing Techniques for High Accuracy Ultrasonic Range Measurements,” IEEE Transactions on Instrumentation and Measurement, Vol. 40. No. 4, 1991, pp. 759-769. doi:10.1109/19.85348
[7] J. Blitz, “Fundamentals of Ultrasonics,” Butterworths, London, Chap. 5, 1967.
[8] F. G. Stremler, “Introduction to Communication Systems,” 3rd Edition, Addison-Wesley Publishing Co., 1990, pp. 195-197.
[9] P. Z. Peebles Jr., “Probability, Random Variables, and Random Signal Principles,” 3rd Edition, McGraw-Hill Book Co., 1993.

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