Search results
Results From The WOW.Com Content Network
Echo sounding or depth sounding is the use of sonar for ranging, normally to determine the depth of water . It involves transmitting acoustic waves into water and recording the time interval between emission and return of a pulse; the resulting time of flight , along with knowledge of the speed of sound in water, allows determining the distance ...
Lead and line sounding. A sounding line or lead line is a length of thin rope with a plummet, generally of lead, at its end. Regardless of the actual composition of the plummet, it is still called a "lead". Leads were swung, or cast, by a leadsman, usually standing in the chains of a ship, up against the shrouds. [4]
Traditionally conducted by ships with a sounding line or echo sounding, surveys are increasingly conducted with the aid of aircraft and sophisticated electronic sensor systems in shallow waters. [citation needed]
Echo sounding is a process used to determine the depth of water beneath ships and boats. A type of active sonar, echo sounding is the transmission of an acoustic pulse directly downwards to the seabed, measuring the time between transmission and echo return, after having hit the bottom and bouncing back to its ship of origin.
Acoustic wayfinding, the practice of using auditory cues and sound markers to navigate indoor and outdoor spaces; Animal echolocation, animals emitting sound and listening to the echo in order to locate objects or navigate; Echo sounding, listening to the echo of sound pulses to measure the distance to the bottom of the sea, a special case of sonar
Systems typically use a transducer that generates sound waves in the ultrasonic range, above 20 kHz, by turning electrical energy into sound, then upon receiving the echo turn the sound waves into electrical energy which can be measured and displayed. This technology, as well, can detect approaching objects and track their positions. [2]
Echo sounding was introduced in the 1920s, and Percy Douglas, hydrographer from 1924 to 1932, was a strong advocate of this method. As well as increasing productivity, it enabled continuous monitoring along a sounding line, reducing the chance of a hazard being missed.
The basic components of the scientific echo sounder hardware function is to transmit the sound, receive, filter and amplify, record, and analyze the echoes. While there are many manufacturers of commercially available "fish-finders," quantitative analysis requires that measurements be made with calibrated echo sounder equipment, having high ...