DIGITAL SENSOR – ECHO SOUNDER

Echo sounder is a type of SONAR (originally an acronym for SOund Navigation and Ranging) used to determine the depth of water by transmitting sound pulses into water. The time interval between emission and return of a pulse is recorded, which is used to determine the depth of water along with the speed of sound in water at the time.

The echo sounder is used in confined waters for navigation purposes for which the echo sounder frequency is set to 50kHz. At this frequency the level of detection of the seabed is about 90-150m, depending on the salinity and temperature of the seawater. However, depths above these levels are not detected. 

Did You Know?

After the disaster of the Titanic in 1912, German Physicist Alexander Behm discovered the technique of echo sounding to find a way to detect icebergs. However, through echo sounding, he failed to detect icebergs but instead it turned out to be a great tool to measure depth of the sea.

The following are the environmental factors that can affect the measurement:

• The state of the sea
• Increase in water temperature in several sea areas
• Noise from bow thrusters, vibration of main engine and reverse rotation of the propeller.