REMOTE GEODETIC OBSERVATORIES

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REMOTE GEODETIC OBSERVATORIES

• L.D. Hothem
• U.S. Geological Survey
• Reston, Virginia USA
• Lhothem_at_usgs.gov
• Lhothem_at_erols.com

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SCAR WG-GGI GIANT ProjectREMOTE GEODETIC
OBSERVATORIES
GOAL To identify technology for the deployment
of Global Navigation Satellite Systems (GNSS)
equipment, tide gage instrumentation, and other
geodetic sensors at unattended remote Antarctic
localities for regional densification of the
geodetic infrastructure, and for scientific
studies of surface geodynamics, ionospheric and
tropospheric refraction models, and
meteorological forecasting models.
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SCAR WG-GGI GIANT ProjectREMOTE GEODETIC
OBSERVATORIES
Activities 1.) Monitor and report on Status
of GNSS and other geodetic sensors Solar, wind
and other methods of power generation Data
communications satellite and terrestrial 2.)
Status report on activities from US
Australia Japan Netherlands New
Zealand Italy Germany Other countries?
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SCAR WG-GGI GIANT ProjectREMOTE GEODETIC
OBSERVATORIES
In past two years, substantial progress has been
made in technology developments, both for sensors
and ancillary support equipment. Experiences
under Review 1) Deployment of GPS or GPS/GLONASS
permanent observatories 2) Tide gage
instrumentation 3) TransAntarctic Mountains
SEISmic experiment (TAMSEIS) 4) Automatic Weather
Stations (AWS) 5) Automated Geophysical
Observatories (AGO)
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SCAR WG-GGI GIANT ProjectREMOTE GEODETIC
OBSERVATORIES
Objectives in Planning New Deployments 1) Keep
it simple - no mechanical devices, if
possible. 2) Option should be available to
collect data at high sample rate in support of
special studies or investigations. 3) Co-locate
with high quality and accurate meteorological
instrumentation 4) If possible, avoid using
wind powered generators. 5) Replace mechanical
hard disk devices for storage media with PC
Flash Cards to help reduce amount of power
required.
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SCAR WG-GGI GIANT ProjectREMOTE GEODETIC
OBSERVATORIES
Geodetic Sensors 1) GPS 2) GNSS integrated
receiver systems In December 2000, installed
GPS/GLONASS dual frequency observatory, TOPCON
Legacy-E, with solar-battery power system, and
hard disk controller. Battery supply
500 amp-hours Solar panels 4ea 40
watt panels for a total of 160 watts Maximum
power required 6.5 watts. Hard disk storage
20 Mb, requires about 3 watts Legacy-E
receiver 3.5 watts Data sampling rate 15
sec. Mask angle 5 degrees 3) Tide gage
Instrumentation
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SCAR WG-GGI GIANT ProjectREMOTE GEODETIC
OBSERVATORIES
Power 1) Batteries 2) Power generation
Wind Solar panels Fuel cells
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SCAR WG-GGI GIANT ProjectREMOTE GEODETIC
OBSERVATORIES
Communication (In cooperation with Mr. Pat
Smith, NSF Coordinator, Electronic Communication
Systems) 1) ARGIS 2) IMARSAT 3) IRIDIUM 4)
Terrestrial systems (may require repeaters)
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SCAR WG-GGI GIANT ProjectREMOTE GEODETIC
OBSERVATORIES
Engineering Factors (1) (Ref RPSC Presentation
August 2000, "Unattended Sensors in
Antarctica") Electronics Electrolytic
capacitors freeze at -56C Heating needed for
some outside electronics Dry environment is a
static discharge hazard Lower power means
lower logistic impact Power Electricity can
be provided by solar, wind or generators
Reliable power requires redundant generation
techniques
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SCAR WG-GGI GIANT ProjectREMOTE GEODETIC
OBSERVATORIES
Engineering Factors (2) (Ref RPSC Presentation
August 2000, "Unattended Sensors in
Antarctica") Fuel Most hydrocarbon fuel
mixtures turn to syrup in Antarctic winter
temperatures. Fuel is heavy - needs airborne
transport to deliver it. Heating structures in
the winter requires large amounts of fuel
Solar Reliable and lightweight, but only
useful when the sun is up. Mounting options
include facing the ground. Not adequate for
heating large structures Wind Riskiest
alternative, problems include turbine icing,
blade fractures, and the need for special low
temperature lubricants.
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Station COAT Established by Carol
Raymond, JPL/NASA, January 1997
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Station COAT
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Station MTCX Established by Carol
Raymond, JPL/NASA, January 1998
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Marie Byrd Land Remote GPS Stations
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Marie Byrd Land Remote GPS Stations
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Mt. Erebus Remote GPS Stations
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Cape Roberts Tide Station, Antarctica, Established
1991 TAMDEF Station ROB0 Established November
1996 Remote GNSS Station ROB1 Established Decembe
r 2000
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Cape Roberts Tide Gage
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Cape Roberts Tide Gage Station
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Calibration of Tide Gage
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TransAntarctic Mountains SEISmic
experimentTAMSEIS
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TransAntarctic Mountains SEISmic
experimentTAMSEIS
This seismic experiment consist of three
elements 1. A 1400 km linear array of 17
broadband seismic stations extending
from the high central regions of the East
Antarctic craton to the TransAntarctic
Mountains (TAM) (Array 1) 2. An intersecting
400 km linear array of 16 broadband seismic
stations crossing the TAM (and array 1)
nearly perpendicular to the first array
(Array 2) 3. 11 broadband stations in the
coastal regions along the TAM and on
Ross Island and Franklin Island (Array 3).
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TAMSEIS Station at Cape Roberts
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CONSTRUCTION OF A LOW POWER CONTINUOUS OPERATING
REMOTE GPS/GLONASS OBSERVATORY IN SOUTHERN
VICTORIA LAND
L.D. Hothem and M.J. Willis US Geological
Survey Reston, Virginia USA
Acknowledgements Land Information New
Zealand JPL/NASA
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Overview (1)

• During 2000-2001 austral summer, installed
  low-power GPS/GLONASS reference station system at
  Cape Roberts
• Station is TAMDEF project benchmark ROB1
• System Design objectives
• Demonstrate and evaluate latest in technology for
  high quality low-power instrumentation
  GPS/GLONASS receiver and storage media
• TOPCON Legacy-E GPS/GLONASS receiver, 3.5 watts
• Demonstrate and evaluate feasibility for
  continuous operation without requiring wind
  generating power system
• Demonstrate future power management and
  upgradability for remote GPS observatories

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Overview (2)

• Station site objectives
• Monitor relationship of Cape Roberts site over
  McMurdo Sound and southern end of the Terror Rift
  relative to IGS station MCM4 on Ross Island
• Data supports research to evaluate tropospheric
  refraction effects
• Supports goals of the SCAR GIANT program and
  ANTEC objectives for optimally spaced GPS
  stations around Antarctica
• Station is co-located with and tied to other
  geodetic observatories (tide gage, seismic
  station, and absolute gravity station)

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Batteries, cables, controller, GPS/GLONASS
receiver, and HD
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Wiring the solar panels
Solar panel installation complete
Complete station installed
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Future Strategies for Remote GNSS Systems

• Reduce power of Cape Robert system by at least
  50 to 3 watts maximum
• Expand battery capacity from 500 amp-hours to
  1000 amp-hours
• Install high-capacity hard storage devices (2Gb
  Flash Disks)
• Install Dorne-Margolin type antennas with SCIGN
  radome
• Install IRIDIUM satellite transceiver for two-way
  communication and daily upload/download capability

SCIGN - Southern California Integrated GPS Network
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Javad Navigation SystemsDual frequency L1/L2
GPS/GLONASS Receiver
EuroCard
Legacy-E
Legacy-H
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Thank you