Reson SeaBat 7125 ROV, Руководство оператора

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SYSTEM PERFORMANCE AND DATA TYPES
SeaBat 7125 ROV Operator‟s Manual
Page 105 May 30, 2011
Version 3
7.2 Equidistant Beamforming
As the beam steering angle increases from nadir, the number of beams per degree of
swath stays constant for equiangular spacing while it increases for equidistant spacing.
Figure 43 presents the number of beams as a function of steering angle for a 1° nadir
beam spacing.
Figure 43: Beam Density
Assuming a flat bottom and using the beam footprint generated by the nadir beam, it
may be seen that the center-to-center spacing for each beam successively reduces as
the departure from nadir increases until at ±65° the beam density is approximately 2.5
times greater than at nadir.
Assuming one sounding is generated from the intersection of the beam center with the
seafloor, in equidistant mode, the appropriate number of beams is formed to maintain
this nadir sounding spacing across the entire swath. See also
Figure 44 .
Reduced Center-to-Center Spacing
at Large Steering Angles
Wider Center-to-Center
Spacing at Nadir
Figure 44: Beam Spacing