Operation Manual
FarSounder, Inc.
F31552 (Rev. 3.8.0)
Page 39 of 69
5. The 3D Sonar Display
5.1. Overview
The 3D Sonar Display is the window where FarSounder's 3D forward-looking sonar information is shown.
In this view, the user is given a 3-dimensional picture of the seafloor ahead of the vessel along with in-
water targets. FarSounder's processing algorithms use spatial classification techniques which are used to
differentiate between the seafloor and in-water targets. The sea floor is displayed as a smooth continuous
surface while in-water targets are displayed as small spheres, also known as voxels, which represent the
target's 3D location.
All FarSounder sonars are specified as 8 water depth sonars. This means that they can map the seafloor out
to a distance of at least 8 times the depth of water in which the sonar is operating. Beyond their water depth
capabilities, the products can still detect in-water targets out to the full range of the system. See Appendix A,
Understanding Water Depth Performance for more information.
All echoes classified as in-water targets are tracked from ping to ping by the signal processing algorithms
in FarSounder's software. If a target is only detected on a single ping, it is hidden from display. This
minimizes false alarms from reflections off of waves and other transient clutter. If a target is tracked across
multiple pings but is not detected on a subsequent ping, the target is shown on the screen at the predicted
location (based on previous target locations and vessel movements). See Appendix B, Ping-to-Ping Target
Stabilization for more information.
The user can select between the 3D volumetric display, which allows the user to rotate the 3D image with
real-time perspective, and the standard display, which shows the 3D information in a look-down display
(much like a radar view, except below the water).
The Sonar View consists of three main components: the 3D volumetric/standard views, the profile view,
and the menu bar. These are shown in the figure below. Additionally, the user can set an alarm, display 2D
depth profiles ahead of the vessel at a user selected bearing, and configure other advanced options in the
display. This display also has various settings available in the Configuration Manager.
5.2. 3D Volumetric/Standard View
This view shows the data in either 3D Volumetric or Standard modes. To switch between these modes,
click the mode button in the menu bar.
In the 3D volumetric mode (see figure 37), the data is shown with shading and perspective. Color can be
mapped to depth (where blue is deep and yellow is shallow) or signal level (where dark brown is quiet and
light copper is loud) as defined in the color scale. Any mouse movement while clicking and holding the left
mouse button will rotate the entire 3D volume of data.
