Echo Sounders

Echo Sounders are used to measure water depth by sending an acoustic pulse to the seafloor and measuring how long it takes to be reflected back to the surface. Single beam echo sounders have a single transducer to transmit and receive sound. Multi-beam echo sounders have many transmit/receive hydrophones and thus cover a much larger area on the seafloor. This greater coverage makes it much quicker to survey a given area. Interferometry based swath bathymetry survey systems offer wide area, high data density coverage and are particularly suited to surveys in shallow coastal regions

The term "interferometry" is generally used to describe swath-sounding sonar techniques that use the phase content of the sonar signal to measure the angle of a wave front returned from a sonar target. This technique may be contrasted with multibeam (and single beam) systems which look for an amplitude peak on each beam in order to detect the sea-bed, or other targets, across the swath. More information may be found here.

For commercial information on a portable single beam echo sounder click here.

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