Operation Manual
FarSounder, Inc.
F31552 (Rev. 2.6.1)
Page 36 of 56
Figure 26. Color mapped to signal strength with "poor" settings
Figure 26, “Color mapped to signal strength with "poor" settings” shows the same ping with "poor" processor
settings. In this image, color has been mapped to signal strength. Red shows that a target is highly reflective,
where blue shows that a target is less reflective. One can clearly see that there is a nice regular looking
sea floor, but there is a lot of in-water target clutter. In this test case, we know that there should be a single
in-water target that is a strong reflector; the piling. In the figure, one can clearly see that there is a single very
reflective in-water target (the red blip). Its position corresponds precisely to where the piling was visually
sighted. All of the other in-water targets are most likely noise blips caused by poor settings. Certainly, there
may be other legitimate in-water targets that are in the water column and not visible to the eye above the
water. However, they would likely be much louder than the sea floor, and nearer to the signal level of the
piling.
Proper adjustment of the Squelch level will remove false in-water targets and clutter.
Noise blips are spurious and are not generally consistent from ping to ping. If an in-water target is detected
on multiple pings, even if it is of a lower signal strength, it is probably a legitimate target. Before changing
the settings too much, look at multiple pings for consistent, low signal strength targets. From this single
image, it is clear that the in-water target cutoff needs to be increased.
Hint: Map color to signal strength in order to identify a single target against noise blips
