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It operates by using a transducer to emit a pulse through the water and listen for echos to return. Using that data, it's able to determine the distance from the strongest echo, which can be the seafloor, a concrete structure, or other larger obstacle. [7] A fishfinder is an echo sounding device used by both recreational and commercial fishers.
Hydrographic survey is the science of measurement and description of features which affect maritime navigation, marine construction, dredging, offshore wind farms, offshore oil exploration and drilling and related activities. Surveys may also be conducted to determine the route of subsea cables such as telecommunications cables, cables ...
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 ...
The first commercial side-scan system was the Kelvin Hughes "Transit Sonar", a converted echo-sounder with a single-channel, pole-mounted, fan-beam transducer introduced around 1960. In 1963 Dr. Harold Edgerton, Edward Curley, and John Yules used a conical-beam 12 kHz side-scan sonar to find the sunken Vineyard Lightship in Buzzards Bay ...
NMEA 0183 is a combined electrical and data specification for communication between marine electronics such as echo sounder, sonars, anemometer, gyrocompass, autopilot, GPS receivers and many other types of instruments. It has been defined and is controlled by the National Marine Electronics Association (NMEA).
A multibeam echosounder is a device typically used by hydrographic surveyors to determine the depth of water and the nature of the seabed. Most modern systems work by transmitting a broad acoustic fan shaped pulse from a specially designed transducer across the full swathe acrosstrack with a narrow alongtrack then forming multiple receive beams (beamforming) that are much narrower in the ...
A transect spacing of 15 nautical miles (17.3 miles) was used. Data from the echo integrator were summed over a 15-min period (2.5n. miles at 10 knots; 1 knot=1.852 km/h). The echo sound provided approximately 2.5*10,000,000 measurements of fish density during acoustic survey of herring population. [2]
Single-beam echo sounders were used from the 1920s-1930s to measure the distance of the seafloor directly below a vessel at relatively close intervals along the line of travel. By running roughly parallel lines, data points could be collected at better resolution, but this method still left gaps between the data points, particularly between the ...