Kongsberg EM 3002, Product Description

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Product description
7
855-164929 / A
The acrosstrack sounding density will limit the usability of the
outer beams in a multibeam echo sounder, unless the beam
spacing is equidistant and the beam pointing angles are roll
compensated, which is the case for the EM 3002. It is common
practice to run a survey with overlap between the neighbouring
lines for quality control purposes. For a high resolution survey it
is recommended that the spacing between neighbouring survey
lines for EM 3002 is limited to about 3 times water depth and at
least twice that with the EM 3002D. These line spacing
recommendations will give an excellent sounding density and
also a good swath overlap between neighbouring lines.
At high frequencies the range performance of any sonar system
is strongly dependent upon water temperature and salinity in
addition to bottom reflectivity.
→
Refer to figure 2.
(CD3209)
Figure 2 Attenuation in water surface. The depth dependence is
negligible except for the temperature reduction with increasing
depth.
The next three figures show the achievable swath width for
different absorption coefficients and bottom types as a function
of depth beneath the transducers for both single and dual head
versions.