06 PowerPoint Briefing style

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Formosat-3 COSMIC Campaign Observations at
Kwajalein Atoll October 18, 2006
Chin S. Lin Space Vehicles Directorate Air Force
Research Laboratory
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Outline

• Introduction
• Formosat-3 COSMIC Campaign Study
• Kwajalein Campaign
• SCINDA Ground Network
• Conjunction Observations of Scintillations
• Conclusion
• Kwajalein Campaign Study Participants
• AFRL/SCINDA Keith Groves, Isseyas Mengistu, Chin
  Lin, Michael Starks, David Hatcher, Santimay Basu
• KRS/ALTAIR Dale Sponseller
• NSPO Tie-yue Liu, Cheng-Yung Huang
• UCAR Stig Syndergaad
• NCU Yen-Shyang Chu

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Formosat-3 COSMIC Campaign Study

• Campaign planning meeting at Baltimore, MD on May
  24, 2006
• Campaign Study Meeting Participants
• COSMIC (Rocken, Syndergaard)
• TIP (S. Basu, Dymond, Coker, Sa. Basu, Budzien)
• TBB Ground receivers (Bernhardt)
• Jicamarca ISR (Hysell)
• Arecibo ISR (Kelley)
• ALTAIR ISR (Groves, Lin)
• SCINDA Network (Groves)
• South America GPS stations (Abdu)
• Pacific Ground Network (Chu, Su)
• Modeling Analysis
• C/NOFS (de la Beaujardiere)
• GAIM (Mannucci)
• RO (Straus)

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Kwajalein Campaign Study

• Objective To study radio occultation and
  scintillations of GPS signals passing through
  equatorial density bubbles
• Campaign study periods
• September 10 22, 2006
• Ground Observations
• ALTAIR ISR
• SCINDA Network (UHF and GOS scintillation
  monitors)
• All sky imager
• Digisonde

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ALTAIR Radio Occultation Scanning Experiment
Problem Variation of electron density along
radio occultation path has unknown effects on
excess phases Abel inversion of electron density
profiles assumes a spherical symmetry in
ionospheric density. Horizontal density gradient
effects unclear.
Proposed Solution Investigate electron density
variation along radio occultation path using
VHF/UF ALTAIR radar at Kwajalein
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ALTAIR VHF Radar Scan Quick Look Plot
Time
Range
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ALTAIR Radar Wide Band Scintillation Echo
Quick Look Plot
18 Mhz Frequency Bandwidth
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Radio Occultation Ray Paths Over ALTAIR
Radio occultation Perigee path
ALTAIR
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(No Transcript)
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Kwajalein Allsky Imager630 nm
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Kwajalein Imager Intensity Along
Formosat-3/COSMIC Track
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SCINTILLATION NETWORK DECISION AID(SCINDA)
A regional nowcasting system to support research
and users of space-based communication and
navigation systems

• Ground-based sensor network
• Passive VHF / L-band /GPS scintillation receivers
• Measures scintillation intensity, eastward drift
  velocity, and TEC
• Automated real-time data retrieval via internet
• Data supports research and space weather users
• Understand on-set, evolution and dynamics of
  large-scale ionospheric disturbances
• Empirical model provides simplified
  visualizations of scintillation regions in
  real-time

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SCINDA Ground Stations
Present and anticipated thru 2008
30N
0
30S
0
210E
240E
300E
330E
60E
90E
120E
150E
270E
30E
Future sites shown represent approximate desired
locations actual sites TBD
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SCINDA Ground Sensor Data at Kwajalein
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Scintillation Index at Kwajalein
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Formosat-3/COSMIC Observations of Scintillations
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Formosat-3/COSMIC Observations
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Ionospheric Electron Density Profile
Inversion from Formosat-3/COSMIC Radio
Occultation
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Kwajalein Digisonde
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Conclusions

• On-going study of scintillations using
  conjunction observations from Formosat-3/COSMIC
  observations, ALTAIR and SCINDA network of
  monitors.
• SCINDA data from a network of 15 stations around
  the globe in conjunction with Formosat-3/COSMIC
  observations are useful for studying the
  characteristics and climatology of equatorial
  scintillation.
• Locations of ionospheric scintillations are to be
  estimated by triangulation from Formosat-3
  satellite and SCINDA ground station.
• Electron density profiles deduced from
  ionospheric radio occultation are to be used to
  examine the relationship between the
  scintillation altitude and the F layer peak
• Electron density distributions from ALTAIR radar
  scatter are to be used to study the impact of
  density gradients on profile inversion techniques