DESCRIPTION

This ship's hull mounted sub-bottom profiler is EdgeTech's long running success story in providing Full Spectrum (“chirp”) imaging systems to customers who need the best in underwater acoustic imaging. Under any conditions when compared to other sub-bottom profilers, EdgeTech provides better images, more deployment options, and interface flexibility.

The 3300-HM Hull Mount System uses special design transmitters with low Q wideband characteristics best suited for “chirp” transmissions. If conventional off-the-shelf transducers are used then there is a need to compensate in software for the narrow band characteristics of the transmitters. The result is visible in the images created.

One of the key features is the ability to put more than one ping into the water column at the same time. The Full Spectrum (”chirp”) signal processing is used to discriminate which of the pulses has been received. Multiple pulses can be stacked up under user control.

Multiple pings maintain an almost constant resolution on the bottom regardless of the water depth.

Selection of array size depends on several factors. The important decision parameter is the water depth in which the system is to be used. For most deployments to full ocean depth a 4 x 4 array will provide the needed performance. A 2 x 2 array should be considered only for coastal applications and water depths to 300 meters.

Several other variables should also be taken into consideration. They include hull type and thickness, shelf-noise, variations in flow noise, ship's speed, sea states, and pitch and roll.

EdgeTech separates the Full Spectrum (‘chirp”) signal processing and the signal amplifier out into separate housings. This lets a user interface to his own or a 3rd party topside display processor for command, control, display, printing and data storage.