Reson SeaBat 7125 SV2, Руководство оператора

Страница: 112 / 212

ACTIVE SONAR USAGE
SeaBat 7125 SV2 Operator‟s Manual
Page 96 July 25, 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
6.6 below
For instructions on how to adjust this setting, see
section 5.7.1.5 Set the Gain .
6.2.5 Vari-Swath
Vari-swath is a feature which allows the operator to select a swath width appropriate to
the application in addition to electronically steering the selected swath.
Vari-swath is available with both EA and ED beam spacing and may be used in
conjunction with roll stabilization (see
section 4.2.7 Motion ) and Flex mode (see section
5.7.1.3 Set the Beam Mode ). It does not work in conjunction with Wide mode.
For instructions on how to adjust this setting, see
section 5.7.1.7 Set Vari-Swath .
6.2.5.1 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.