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ANCHORSynergies with Global-scale efforts
Bruce M. Howe
Acoustic Navigation and Communication for High-latitudeOcean Research (ANCHOR) Workshop
Applied Physics Laboratory, University of Washington,
27 February – 1 March 2006
Outline of Talk
• A little history and background
• ASA Integrated Acoustics Systems for Ocean Observatories
• GPS
• ORION status
• ORION acoustics
• Connection to ANCHOR
History• Sun, moon, stars, terrain/feature tracking• Compass, sextant and variants• Time – longitude• Time standards – 1930s Einstein’s predictions of effect
of gravity on time. Nobel Prizes: Rabi 1944 atomic resonance; Ramsey 1989 hydrogen masers
• Radio, loran, mini-ranger, … • Satellites
– Sputnik – Doppler navigation– Transit satellites 1965 (a few fixes/day, 15 min integration) for
Polaris subs– GPS – one Sept weekend, 1973, full coverage time and space
• Deep space network – nav and comms -> deep space internet, infrastructure around Mars, occultations
• Underwater – SOSUS, Navy ranges, LBL, FLBL, Swallow/SOFAR/RAFOS/mobile/tomography
Acoustics in Ocean Observatories
• Acoustic methods will be ubiquitous in ocean observing– Ocean is transparent to sound, but largely
opaque to electromagnetic radiation– Provides synoptic, volumetric sampling
• Cross cuts across many disciplines – opportunities for synergies and integration
Integrated Acoustics Systems for Ocean Observatories (IASOO)
OceanAcoustics
GPS/cellConcepts
OceanObservatories
IASOO
Science Communication
Navigation
Unified architecture across all scales
ASA-AO committee
2003
IASOO Concepts• Acoustic sources act as “GPS satellites” underwater to
provide signals for – Navigation– Communication – Science
• Receivers on all platforms• Simultaneously
– Ambient sound (wind, rain, seismic, whales, shipping, …)– Tomography– Others
• 2-way communications as appropriate• Manage the acoustic spectrum – all users• Unified architecture across all scales
ORION Workshop
ice• Jan 2004 Puerto Rico
• Recognized as part of observing system
Projection slice theorem
Norton: – if sensors only on periphery, only get vorticity, not divergence
Global Navigation Satellite Systems
GPS GlonassGalileo
---------------
60–90sourcesin space
GEONET
Japanese Meteorological Agency, 2003
Maps of Precipitable Water (PW)
GPS Experience
• Huge user base has evolved• >3000 science receivers – international data
centers• GPS Navigation message
– 50 b/s, 20% parity bits, 1 of 10 words for sync, 30 s– Clock correction– Ephemeris (orbits/position/velocity)– Ionospheric correction parameters– UTC information– Almanac
• Differential measurements, WAAS, quality, …
Back to the ocean
• Major NSF Ocean Sciences Program started 2004
• Infrastructure MRE funds $309M in FY2007!!!
• PLUS all science, O&M, DMAS, E&O, … 30 years
• www.orionprogram.org
Elements• Sustained presence – research and operations
– power and comms (x,t)
• Three Components– Regional, cabled +– Coastal, cabled, moor, +– Global, Moorings NSF
ORION
IOOS
Distributed sensor systemNavy example
• Environmental assessment defines cluster topology and fixed/mobile mix
• Fixed and mobile sensor nodes deployed for optimum coverage. AUV’s enter semi-dormant state as temporarily fixed or drifting nodes
• Reconfigure mobile sensor nodes based on current environmental situation
• Event detection communicated to network (ACOMMS or RF)
• Mobile platforms respond
NEPTUNE – in progress• NEPTUNE
Canada• Install summer
2007• 2-4 nodes, to
Endeavor• Loop design• CDN$40M• With Alcatel
• Test beds• MARS and
VENUS
Mid-2006
Mid-2006
Late 2005
ORION RFA concept proposals• 5 major acoustic, 12 others, 17 acoustic out of 48 total –
ORION recognizes acoustic components• Worcester et al.: Thermometry, support navigation, ambient
sound, t-phase• Duda et al.: float tracking (process studies) and thermometry• Detrick et al: geophysical, called for bottom/sofar hydrophone,
Stephen et al – sofar t-phase• Daly et al., Barth et al.,: NEPTUNE/coastal multipurpose
mooring array, tomography• Horne/fish/mammals• Bioacoustics observatory/hawaii• 3 ambient sound (1 with CO2)• Small scale tomo/vents• Many with gliders and AUVs with navigation implied
Daly et al.
• Water column oceanography
Worcester et al• Thermometry
• Also navigation
Duda et al
• Precise float tracking
• Dispersion
• Meridional overturning
• Thermometry
Alternate Source Test (AST)
• 28 and 84 Hz• Simultaneous signals, phase locked (3rd harmonic)• Source from DP ship, DGPS• Deployed in deep water near Pioneer Seamount, 1995
Main Points• Applicable to all cases:
– Timing is fundamental– Navigation implies communications– Tomography results (sound speed and velocity)– All signal compatible– Ambient noise – spectrum, marine animals– GPS is a good analogy– Work to inexpensive receiver– Modeling and data assimilation crucial – start/continue now– Equipment needs (Arctic and lower latitudes) are similar
• Arctic Data N ~ S x R, say S = 5(6)– Fixed N = (5 x 4) / 2 = 10 (15)– Add 16 tethered (x,t known), add N = 5 x 16 = 80 (96)– Add 32 mobile (x,t unknown), add N = (5-3) x 32 = 64 (96)– Total – 154 (207) independent ocean samples each ping
Path
• Need roadmap
• More funding!
• Next MREs, other, …
• Expect 10 years for big chunks – BUT play up short, critical time frame