IMAGENEX DT101Xi, Техническое руководство

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Figure 3-6 Line spacing example [Manual on Hydrography]
For Special Order and Order 1a surveys, no recommended maximum line spacing is given as there is an
overriding requirement for full sea floor search and it is generally recommended that line spacing be such
that 100% overlap per swath is achieved. This is because outer beams on all MBES systems are prone to
anomalies and degradation [Grządziel, Wąż 2016], in all water depths. As a result of amongst others,
environmental issues like SV,
and reflective considerations like beam grazing on acoustically inert seabed’s,
outer beams can be rendered unusable. A large percentage overlap can allow trimming of offending outer
beams, and thus improve quality of acquired data. See Figure 3-7 100% Beam Overlap.
Figure 3-7 100% Beam Overlap
As a general guide, the equation below (Eq 2) may be used to approximate the line spacing:
𝐿𝑆 =
1 + 𝐴
2
. 𝑍. tan (
∅
2
)
(Eq 2)
Line 1 Line 2
Line 3
50%
50%