Monitoring of ocean current perturbations using acoustic phase variations

• Autorzy: Zieliński A. , Butowski M. , Kraeutner P.
• Języki publikacji: EN

Abstrakty

EN

In this paper, we review an acoustic method for measuring both average ocean current speed and sound speed along an acoustic path. The method requires two or more stations on the sea floor, synchronized through a connecting underwater electric cable, that can transmit and receive an acoustic signal and The method is based on reciprocal acoustic transmissions to determine time of flight in both the forward and reverse directions. A specific implementation of this method is proposed. We also consider a novel method for monitoring ocean current perturbations through acoustic phase measurements. In simplest form, a continuous sinusoidal signal is transmitted from one station to a second station. Any variations in ocean current speed will introduce a phase shift in the received signal proportional to the time derivative of the current speed. This effect has been demonstrated through ultrasonic in-air experiments. Finally, the two methods are combined into a single system that continuously measures small-scale ocean current velocity changes.

Słowa kluczowe

EN

ocean current perturbations; acoustics phase variations; hydroacoustics

• Wydawca: Polskie Towarzystwo Akustyczne. Oddział Gdański
• Czasopismo: Hydroacoustics
• Rocznik: 2009
• Tom: Vol. 12
• Strony: 237--248
• Opis fizyczny: Bibliogr. 11 poz., rys., tab., wykr.

Twórcy

autor

Zieliński A.

autor

Butowski M.

autor

Kraeutner P.

• Department of Electrical and Computer Engineering, University of Victoria, Victoria, B.C. V8W 3P6 Canada,

Bibliografia

• [1] Knauss, J., Introduction to Physical Oceanography. Upper Saddle River, NJ: Prentice Hall, 1997, pp. 138.
• [2] Zheng, H., Gohda, N., Noguchi, H., Ito, T., Yamaoka, H., Tamura, T., Takasugi, Y., Kaneko, A., “Reciprocal Sound Transmission Experiment for Current Measurement in the Seto Inland Sea, Japan.” Journal of Oceanography, vol. 53, 1997, pp. 117-127.
• [3] de Coulon, F., Signal Theory and Processing. Dedham, MA: Artech House, 1986, p. 249.
• [4] Carlson, A., Communication Systems. 2nd ed. New York: McGraw-Hill, 1975, pp. 156-158.
• [5] Liu, H., Ghafoor, A., Stockmann, P.H., “A New Quadrature Sampling and Processing Approach.” IEEE Transactions on Aerospace and Electronic Systems, vol.25, no.5, pp.733-748, Sep 1989.
• [6] Xiong, X., Zielinski, A. “An Adaptive Algorithm for Amplitude and Phase Measurements Based on Multiple Sampling.” Oceans 2007 Conference, Vancouver, September 29 - October 4, 2007, 6 pages, paper 070426-014 (on CD).
• [7] Weisstein, E., “Nonlinear Least Squares Fitting.” MathWorld: A Wolfram Web Resource. http://mathworld.wolfram.com/NonlinearLeastSquaresFitting.html.
• [8] Alexandrov, T., Bianconcini, S., Dagum, E.B., Maass, P., McElroy, T., “A Review of Some Modern Approaches to the Problem of Trend Extraction.” Statistical Research Division U.S. Census Bureau, March 2008.
• [9] IXSEA, “GAPS – Portable, Calibration Free USBL.” http://www.ixsea.com/pdf/2008-01-ps-gap.pdf.
• [10] Spectracom, “Epsilon Clock Model EC1S.” http://www.spectracomcorp.com/Portals/0/products/pdf/Epsilon_Clock_Model_EC1S.pdf.
• [11] Zielinski, A., Zhou, L., Butowski, M., “Ocean Average Current Measurement Using Acoustic Phase Monitoring.” Hydroacoustics, Vol. 11, Gdansk, May 2008, pp. 459-466.