Performance of an absolute velocity profiler based on acoustic doppler and electromagnetic principles
Citable URI
https://hdl.handle.net/1912/10600DOI
10.1575/1912/10600Abstract
This report describes the performance of a freely-falling velocity
profiler called the Absolute Velocity Profiler (AVP) . The AVP is
distinguishable from our previously developed velocity profiler the
Electro-Magnetic Velocity Profiler (EMVP) in that acoustic Doppler
measurements are used, to determine the reference velocity for the
EMVP profiles. The AVP contains the essential measurements of the
motional electric currents in the sea as implemented in the EMVP and
in addition, collects acoustic Doppler measurements of frequencyshifted
bottom echoes. The former measurements yield a profile of
the horizontal components of velocity relative to a reference velocity,
independent of depth, while the latter measurements determine the absolute
velocity of the AVP vehicle with respect to the sea floor.
The EM profile is obtained from the sea surface to bottom, and the
acoustic Doppler measurements are made within about 300 m of the sea
floor. The combination of the EM and acoustic Doppler measurements
yields an absolute velocity profile throughout the water column. Performance
analyses included in this report set method uncertainties of
between 1 and 2 cm/s r.m.s. Measurements of temperature and its gradient
are also made.
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Suggested Citation
Technical Report: Dunlap, John H., Sanford, Thomas B., Drever, Robert G., "Performance of an absolute velocity profiler based on acoustic doppler and electromagnetic principles", 1978-03, DOI:10.1575/1912/10600, https://hdl.handle.net/1912/10600Related items
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