JPL GNSS RO Instrument Technology Update

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JPL GNSS RO InstrumentTechnology Update
Tom Meehan, Stephan Esterhuizen Larry
Young Jet Propulsion Laboratory California
Institute of Technology Pasadena, CA USA
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Intention

• A little about current instrument and how it
  relates to GPS Limb Viewing
• Things expected of a new instrument in terms of
  CPU DSP and better observations
• Additional Possibilities from Recent NASA/JPL
  Technology

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Global Atmospheric Refractivity
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Observing Scenario

• Spacecraft Provides Point of View and Ray
  Motion Through the Atmosphere
• The Purpose of the GPSRO Instrument Is to Record
  the Ray Motion (and Amplitude) and Position

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Current Scenario(The COSMIC Setup)
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Observing Geometry
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The nature of onboard occ processing
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Data Collection Options(Downlink forces mode 3)

• Very Wideband Digital Recording
• No OL Model, Simple HW, but... 800 GBytes/Day
  Intensive Ground Based Processing
• Moderate Wideband Digital Recording
• Needs Only Geometric Model, Special DSP HW, 450
  MBytes/Day
• Narrowband Digital Recording ( BlackJack)
• Needs Accurate Model ( 10 Hz) but only
  50MBytes/Day

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The Nature Real-time Occ Processing
?
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The problems of real-time occ processing
?
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Current Scenario(The COSMIC Setup)
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TriG Scenario(The COSMIC-II Setup)
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What Do We Want?

• Very Wideband Digital Recording
• Moderate Wideband Digital Processing/Recording
• Narrowband Digital Formatting ( FFT?)

Also

• Digital Beam Forming for Better SNRNew GPS and
  Galileo SignalsMore Flexibility for Future Stuff

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A slightly different architecture
TriG
RF from Antenna
Climate, Weather, Iono
New Obs Types
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GPSRO Opportunities
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Wrapping Up

• Next Gen Instrumentation (TriG) Provides New
  Science Options
• Science Processor is Linux based File system
  Scriptable interface
• COSMIC-I level of observation can be kept safe
  while new observations tested
• Benefits of standard test apparatus ITAR?
• NOT Requirement Driven but HW Provides For
  Discovery of Future Requirements

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Thank You