摘要 |
A method for the acoustic surveying of the surface contours of the bottom of a body of water by means of a crossed fan beam echo sounding arrangement wherein, for the purpose of obtaining an accurate, unfalsified surface contour, the measured contours obtained by scanning the bottom of the body of water in a direction transverse to direction of the heading of the surveying ship are recalculated by means of a continuously checked and adapted correction value. The correction value is determined from deviations between a calibration contour and a test contour. The calibration contour is a longitudinal contour which is formed from measured contours lined up in the direction of the ship's heading and cover a strip on the bottom of the body of water extending perpendicularly below the path traversed by the surveying ship. The test contour is recorded in the same manner as the measured contour but with the echo sounder pivoted by 90 DEG about the elevation axis of the ship, i.e. from the same strip of ground perpendicularly below the fore-to-aft axis of the ship with which the calibration contour is associated.
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