Reson SeaBat 7125 ROV, Руководство оператора

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ACTIVE SONAR USAGE
SeaBat 7125 ROV Operator‟s Manual
Page 86 May 30, 2011
Version 3
6.2.4 Receiver Gain
The SeaBat system utilizes Time-Varied Gain (TVG) by applying a variable gain to the
signal, based upon the formula in
Table 1 .
Table 1: TVG Formula
Receiver Gain = 2 α R
km
+ Sp log R
m
+ G
Where:
α
= Absorption loss in dB/km
Sp = Spreading loss coefficient
R
km
= Range in kilometers
R
m
= Range in meters
G = Extra gain from RxGain menu item
For details on environmental conditions such as absorption and spreading, see section
6.5 below .
For instructions on how to adjust this setting, see
section 5.7.1.4 Set the Gain .
6.2.5 Variable Swath
The benefits of the variable swath feature are twofold:
Increased sounding density in a small sector may be used when tracking
pipes or other linear features, where the operator is not interested in data
outside a defined sector. The increased sounding density helps define small
targets.
A reduced swath width allows an increase in ping rate for any given depth.