Simrad ES80 Reference Manual page 305

Noise estimate
For every transmission ("ping") the ES80 measures the echo levels along the
chosen range. Typically, these measurements are made every five meters, even for
long ranges.
All echoes and noise in the water are recorded. This includes noise generated by
your own vessel (electric, propellers, machinery etc), water flow, cavitation and
interference. Echoes from fish and other species, as well as from the bottom, are
detected and added to the equations.
By comparing these measurements, the ES80 calculates a noise estimate.
Tip
If you set the ES80 to Passive mode, all echoes from the transmissions are removed
from the equations. This gives you with better information about the actual noise.
If you wish to switch to Passive mode, use the
Normal Operation
This information is also provided on the
Equipment) dialog box. You open the
Equivalent ambient noise
The noise estimate provided by the ES80 includes all noises. This includes noise
generated by your own vessel, for example electric noise, propellers, machinery
and mechanical vibrations. By means of additional equations, the noise values are
compensated for the bandwidth. The equivalent ambient noise value attempts to
present the total noise as if it was all from ambient sources.
This information is also provided on the
Equipment) dialog box. You open the
Related tasks
Selecting Normal mode, page 81
Selecting Inactive mode, page 82
Selecting Replay mode, page 83
Selecting Passive transceiver mode, page 159
Adjusting the output power, page 160
Adjusting the pulse duration, page 160
Defining the frequency sweep (chirp) within each transmission, page 161
Defining the pulse type for the ES80 transmissions, page 162
Related functions
Operation function, page 315
406273/C
dialog box is located on the
BITE
BITE
Normal Operation
menu.
Operation
page in the
Noise BITE
dialog box from the
page in the
Noise BITE
dialog box from the
Menu system
dialog box. The
(Built-In Test
menu.
Setup
(Built-In Test
menu.
Setup
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