EurOCEAN 2000 - Vlaams Instituut voor de Zee

Range finding can be attained by operation of either the dipole or loop antennae since both are
capable of operating in the near field over a distance of 50m and longer if the frequency is
reduced to below 1MHz. Propagation over shorter distances can be obtained by using higher
frequencies. These operating conditions are suitable for object recognition. The detection of
solid matter such as fish will also be observable either by interrupting the beam or by operating
in a radar manner with back-scatter from objects being detected.
REFERENCES
• S. Bogie, “Conduction and Magnetic Signalling in the Sea”, The Radio and Electronic
Engineer, 1972, 42, 447-452.
• D. Scott and G. S. Smith., “Measurement Techniques for Antennas in Dissipative Media”,
IEEE Trans. on Antennas and Propagation, 1973, 4, 499-506.
• M. Siegel and R. W. P. King, “Electromagnetic Propagation Between Antennas
Submerged in the Ocean”, IEEE Trans. on Antennas and Propagation, 1973, 4, 507-513.
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