Context
The RCG (Reverberation Controlled Gain) controls the receiver processing. The algorithm handles each receiver beam individually. The filter reduces the unwanted echoes from the bottom and from the sea surface. This enhances the visibility of schools.
NoteThe numerical settings do not express an increasing filter strength. They represent specific settings using different algorithms.
The algorithms in the filter may interpret scattered fish as reverberation. Use reverberation controlled gain carefully if you wish to detect scattered fish.
TipWe recommend that the reverberation controlled gain is active all the time, but be careful in the vertical presentation.The filter works best on small schools. This rough guide to the settings can be used as a starting point for own experiments.
|
2 |
Use for schools with higher density. |
|
3 |
Use for schools close to bottom. This setting will also reduce the bottom echoes. |
|
4 |
Use for scattered fish. |
|
5 |
Use for scattered fish. This setting uses a slightly different algorithm than the other scattered fish settings. |
|
6 |
Use for schools. This setting uses a slightly different algorithm than the other school settings. |
|
7 |
Use for schools. This setting uses a slightly different algorithm than the other school settings. |
|
8 |
Use for scattered fish. This setting uses a slightly different algorithm than the other scattered fish settings. |
|
9 |
Use for scattered fish. This setting uses a slightly different algorithm than the other scattered fish settings. |
The filters in the ST90 are implemented in “series”. The reverberation controlled gain adjustment is made late in the sequence, so any changes to the preceding filters may have
an effect on how it works.