OVERVIEW: Echo sounders are sonar-based systems used for measuring water depth and mapping the seafloor. They are essential for hydrographic survey, navigation safety, and seabed classification.

GENERAL DESCRIPTION: Echo sounders emit acoustic pulses downward and measure the time taken for the echo to return after hitting the seabed, calculating depth based on sound velocity in water. Single-beam echo sounders emit one narrow beam and provide depth along a single line beneath the vessel, ideal for basic navigation or point-based surveys. Multi-beam echo sounders, in contrast, emit multiple beams to cover wide swaths, producing high-resolution bathymetric maps of the seafloor. They are used extensively in hydrographic mapping, mine countermeasures, underwater construction, and scientific research.

ROLE SUMMARY:
Category: Underwater Mapping / Navigation Aid
Primary Use: Depth sounding and seafloor mapping
Function: Emission of acoustic pulses and measurement of return time
Platform: Survey vessels, submarines, unmanned surface vehicles, AUVs
Integration: Often used alongside GPS, INS, and onboard sonar suites

See Specific information under [Sensors/EW] section.

SOURCE:
International Hydrographic Organization (IHO) Publications
https://en.wikipedia.org/wiki/Echo_sounding