EM710 Water Column Sonar Data Collected During SKQ201507T
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title: EM710 Water Column Sonar Data Collected During SKQ201507T
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abstract: Transit (SKQ201507T, EM710)
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positionName: Water Column Sonar Data Manager
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keyword: Earth Science > Oceans > Ocean Acoustics > Acoustic Scattering
keyword: Earth Science > Oceans > Aquatic Sciences > Fisheries
keyword: Earth Science > Oceans > Ocean Acoustics
keyword: Earth Science > Biosphere > Ecosystems > Marine Ecosystems > Pelagic
keyword: Earth Science > Biosphere > Ecosystems > Marine Ecosystems
keyword: Earth Science > Biosphere > Ecosystems > Marine Ecosystems > Benthic
keyword: Earth Science > Biosphere > Ecosystems > Aquatic Ecosystems
keyword: Earth Science > Oceans > Bathymetry/Seafloor Topography > Bathymetry
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keyword: In Situ/Laboratory Instruments > Profilers/Sounders > Acoustic Sounders > WCMS > Water Column Mapping System
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otherConstraints: Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.
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useLimitation: These data are considered raw and have not been subjected to the NOAA's quality control or quality assurance procedures. They are released for limited public use as preliminary data to be used only with appropriate caution. NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.
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beginPosition: 2015-07-05T02:41:33
endPosition: 2015-07-07T21:32:12
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orderingInstructions: Contact the NCEI Water Column Sonar Data Manager to order data.
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name: Kongsberg EM710 water column data (.wcd) format
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specification: Kongsberg/Simrad .raw files are generated by ME70, EK60 or ES60 instruments. They contain power and optionally angular position data with each beam/frequency identified by an independent channel. See the Simrad interface specification manual for further information. The .wcd files are generated by Kongsberg EM302 or EM122 instruments. See Kongsberg documentation for more information.
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description: The EM 710 multibeam echosounder is a high to very high resolution (up to 800 soundings per ping) seabed mapping system capable of meeting all relevant survey standards. The system configuration can be tailored to the user's requirement, allowing for choice of beam widths as well as transmission modes. The minimum survey depth is from less than 3 meters below the transducers, and the maximum depth is approximately 2000 meters, somewhat dependant upon array size. Across track coverage (maximum swath width 140ú) is up to 5.5 times water depth, to a maximum survey depth more than 2000 meters. The along track beamwidth depends upon the chosen transmit transducer configuration with 0.5ú, 1ú and 2ú available as standard. The receive beam width is either 1ú or 2ú depending on the chosen receive transducer. The EM 710 operates at sonar frequencies in the 70 to 100 kHz range. The transmit fan is divided into three sectors to maximize range capability, but also to suppress interference from multiples of strong bottom echoes. The sectors are transmitted sequentially within each ping, and uses distinct frequencies or waveforms.
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code: Kongsberg EM710
type: Multibeam Echosounder
description: The EM 710 multibeam echosounder is a high to very high resolution (up to 800 soundings per ping) seabed mapping system capable of meeting all relevant survey standards. The system configuration can be tailored to the user's requirement, allowing for choice of beam widths as well as transmission modes. The minimum survey depth is from less than 3 meters below the transducers, and the maximum depth is approximately 2000 meters, somewhat dependant upon array size. Across track coverage (maximum swath width 140ú) is up to 5.5 times water depth, to a maximum survey depth more than 2000 meters. The along track beamwidth depends upon the chosen transmit transducer configuration with 0.5ú, 1ú and 2ú available as standard. The receive beam width is either 1ú or 2ú depending on the chosen receive transducer. The EM 710 operates at sonar frequencies in the 70 to 100 kHz range. The transmit fan is divided into three sectors to maximize range capability, but also to suppress interference from multiples of strong bottom echoes. The sectors are transmitted sequentially within each ping, and uses distinct frequencies or waveforms.
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deliveryPoint: P.O. Box 483
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country: Norway
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code: Kongsberg EM302
type: Multibeam Echosounder
description: The state of the art 30 kHz EM 302 deep water multibeam sonar is manufactured by Kongsberg, Inc of Norway. The EM 302 transducers are modular linear arrays in a Mills cross configuration with separate units for transmit and receive. This sonar offers significantly larger swath width, increased data density and resolution. Beam focusing is applied both during reception and transmission. The system has up to 288 beams / 432 soundings per swath with pointing angles automatically adjusted according to achievable coverage or operator defined limits. In multi-ping mode, 2 swaths are generated per ping cycle, with up to 864 soundings. With multi-ping the transmit fan is duplicated and transmitted with a small difference in along track tilt. The applied tilt takes into account depth, coverage and vessel speed to give a constant sounding separation along track. The beam spacing can be adjusted as equi-distant or equi-angular. EM 302 uses both CW pulses and FM sweep pulses with pulse compression on reception, in order to increase the maximum useful swath width. The transmit fan is split in several individual sectors with independent active steering according to accomplish compensation for the vessel movements: yaw, pitch and roll. The high density, high resolution, large coverage and water column capability makes EM 302 an ideal system to explore the sea bed and the water column for detection and characterization of a broad spectrum of features.