The major problems associated with implementing synthetic apertures in sonar may be overcome by applying the technique to sub-bottom imaging. The use of a low frequency aids both penetration of the sediment and the attainment of long coherent apertures. The implementation of synthetic apertures realises a narrow fan beam. By directing this beam out sideways, a more rapid survey rate is possible than that achieved by the normal echo-sounding mode used in sub-bottom profiling. The synthetic aperture technique appears to offer significant advantages over that of parametric arrays, for high resolution sub-bottom imaging. Synthetic apertures have been implemented in a laboratory tank, under controlled conditions at a fresh water reservoir, and under realistic operational conditions at sea. Encouraging results have been obtained.
Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:uct/oai:localhost:11427/21962 |
Date | January 1986 |
Creators | Dutkiewicz, Marek Karol |
Contributors | Denbigh, P N |
Publisher | University of Cape Town, Faculty of Engineering and the Built Environment, Department of Electrical Engineering |
Source Sets | South African National ETD Portal |
Language | English |
Detected Language | English |
Type | Master Thesis, Masters, MSc (Eng) |
Format | application/pdf |
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