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Dr. Keith GrovesInstitute for Space ResearchBoston CollegeChestnut Hill, MA [email protected]
SCINDA Status & Plans
LISN WorkshopSao José dos Campos
S.P., Brasil7-10 November 2011
Acknowledgments to the Team
Santimay Basu Ronald Caton Charlie Carrano
Chris Bridgwood Isseyas Mengistu John Quinn
Robert Livingston Stephen Jimenez Cesar Valladares
Randy Cicale Ben Heruska Peter Ning
Mike Verlinden Dean Anneser Rui Fernandes
Patrick Roddy Nelson Bonito Ted Erickson
AND a long list of instrument hosts!
• SCINDA Purpose & Status− Equipment Description− Global Scintillation & Ionospheric Monitoring
• African Initiative • Plans & Summary• A bit about COPEX…
OUTLINE
PRN 7
Scintillation: Why we care
• Regional UHF SATCOM outages for extended periods (hours)• Increased Global Positioning Satellite (GPS) navigation errors• Degraded High Frequency (HF) radio communication
Scintillation = Rapid amplitude and phase fluctuations ofradio signals from space due to turbulence generated by Ionospheric Irregularities
SCINTILLATION NETWORK DECISION AID(SCINDA)
• Ground-Based Sensor Network– Passive UHF / L-Band /GPS
Scintillation Receivers– Measures Scintillation Intensity,
Zonal Drift Velocity and TEC– Automated Real-time Data Retrieval
Via Internet
• Data Drives Equatorial Scintillation Model Providing Simplified Visualizations for users
• TEC data available for ambient ionosphere models
A regional nowcasting system to support basic research and users of
space-based comm/nav systems
SCINDA Sensor Suite
GPS Antenna
UHF Antenna
Tri-band Beacon System
GPS Receiver
UHF SATCOM Receiver
Typical Hardware Configuration
cable out to
antennas
Shared Monitor
VHF Computer GPS Computer
VHF Receiver
Internet / Local
Network
GPS Receive
r
KVM Switch
Keyboard
GPS Antenna
West Receiver East Receiver
50-150 meters
2 meters
RG9913 Coaxial Cable(180 meters max.)
Magnetic E-W Baseline
Figure 5. VHF (250 MHz) Receiver Chain and Data Acquisition System
Antenna Layout
Receivers Set-Up
Software Digital Radio Technology
Example of good agreement with the old system (red) and the software digital radio (green) during a strong scintillation period.
Software-based system exhibits lower noise floor
• Measures full spectrum of satellite channels simultaneously
• 1/10 the cost of existing UHF SATCOM monitoring systems
– Enables sensor proliferation for data-starved models!
• Real-time processing capability being tested now for field deployment in FY10
SDR captures entire UHF SATCOM spectrum; collectively a good channel is always available
Any single channel subject to satellite modulation
Present and anticipated thru 2012
SCINDA Ground Stations
30N
0
30S
210E 240E 270E 300E 330E 0 30E 60E 90E 120E 150E
Existing Sites Future UN ISWI Sites Other collaboration
LISN DomainRecent
SCINDA Focus
Scintillation Activity in Africa
• Scintillation activity across Africa assumed high based on satellite observations, but ground-based measurements are needed
• C/NOFS sees similar maximum in activity over Africa
• Leveraged UN-sponsored workshops to identify host nation partners & collaborators (2005-09)
• Goal is to establish robust monitoring network with scientific collaboration across Africa, Asia and South America
Strength of scintillations over Africa unknown
Adapted from S.Y. Su, 2005
• 1st Workshop: 10-14 Jul 2006, Espargos, Sal Island, Cape Verde– 20 African participants, installed full SCINDA sensor suite, outlined plan for new sites– As a result, established 3 SCINDA sites in Nigeria (2) and Ivory Coast in 2007
• 2nd Workshop: 11 Nov 2007, Addis Ababa, Ethiopia– More than 50 participants representing 12 nations – Results of initial research on SCINDA data from and presented by African hosts– Established 3 SCINDA sites in Ethiopia (2) and Kenya in 2008
• 3rd Workshop: 7-12 Jun 2009, Livingstone, Zambia– More than 100 participants representing 25 nations!– Presentations and discussions of research on SCINDA data led by African scientists!– Deployed 5 systems to Uganda, Egypt, Liberia, Nigeria & Kenya and plans for future
deployment of up to 10 more systems in Africa
• 4th Workshop 6-10 Nov 2010 in conjunction with Workshop on International Space Weather Initiative (ISWI), Helwan, Egypt
SCINDA-IHY Workshops in Africa
11
Purpose: To train participants in equatorial Ionospheric physics and SCINDA sensor installation, operation and maintenance
10-14 Jul 2006 – Espargos, Cape Verde
1st SCINDA-IHY Workshop in Africa
11 Nov 2007 – Addis Ababa, Ethiopia
2nd SCINDA-IHY Workshop in Africa
Bigger…
7-12 Jun 2009, Livingstone, Zambia
3rd SCINDA-IHY Workshop in Africa
Still Growing…
2011-2013 Plans (unofficial)
• Install an additional 4-5 sites in Africa, 2-3 other locations in S.E. Asia/Pacific
• Improve infrastructure/capability at functional sites in Africa
– Solar panels, robust power systems, mobile data transfer
– Add VHF scintillation/drift sensors
• Develop improved multi-frequency LEO beacon receiver systems focused on next-generation beacon design (still TBD); up to six equatorial satellites in constellation (2015)
– New sensors useful throughout SCINDA & LISN networks
Basic Infrastructure NeedsCongo Brazzaville, 2-6 Nov 2011
VHF & GPS Sensor DataNairobi, Kenya, 01 Oct 2011
2011-2013 Plans (unofficial)
• Exploit data for more scientific studies on both local and global scintillation phenomena
– Storm-time behavior, 4-cell pattern in TEC/scintillation, local gradients, anomaly characteristics
– Ultimate goal is to forecast equatorial Spread F
Mla
t
VTEC
Meridional Structure & Evolution: COPEXTEC Central Brazil Oct-Nov 2002
• Combined data from three (3) stations reveals dramatic low latitude density structure and variation
• Asymmetric anomaly structure driven by inter-hemispheric neutral wind
• Scintillation characteristics symmetric
Local Time
VTEC
Mla
t
Local Time
VTEC
13-19 October
3-9 November 1-7 December
Longitudinal Variations: Continental Scale
Synoptic scale features can be resolved with current network, but better resolution is needed
ASI
KIN
ZNZ ZNZ ZNZ ZNZ
ASI ASI ASI
KIN KIN KIN
EA
ST
WE
ST
CE
NT
RA
L
14 Oct 15 Oct 16 Oct 27 Oct
2011-2013 Plans (unofficial)
• Continue to support LISN initiative—South America is critical region and offers excellent observing opportunities
Recent SCINDA Installations
GPS site established in Zanzibar, Tanzania July 2010VHF system installed in Nairobi, Kenya
GPS sites established in Kinshasa & Kisangani, DRC May 2011
More SCINDA Site Photos
TIA (This is Africa)
TIB (This is Brasil)
Obrigado