NASA Search and Rescue Program
Dr Lisa Mazzuca
Dr.
NASA SAR Deputy Mission Manager
NASA Search and Rescue Mission Office
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NASA’s role in SAR
• GSFC is NASA’s Center of Excellence for Scientific Research
− world leader in satellite development and space communications
• NASA/GSFC has 30 years of SARSAT experience
−Developed existing and future SARSAT systems - LEO, GEO, now MEO
−Development
Development includes all segments of the SARSAT system
−User segment – emergency beacons
−Space segment – POES, GOES and GPS
−Ground segment – LEO, GEO, and MEO ground stations
− SARLab facility provides all infrastructure necessary for system development and
testing
−Copies of current operational systems (LEO and GEO)
−World’s first prototype of next generation MEO system (DASS)
−Beacon
Beacon simulators and test facilities
−Experienced staff with vast system design and test experience
• Support National Search and Rescue Committee (NSARC), Coast Guard, Air
Force and NOAA
Force,
• Support international COSPAS-SARSAT organization and partners
NASA Search and Rescue Mission Office
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System Overview
NASA Search and Rescue Mission Office
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SARSAT Timeline
Cospas-Sarsat
Program
established by
international agreement
(
(ICSPA)
)
 Establishes Council
and Secretariat
• Provides framework
for other countries to
join
• Provides framework
f system
for
t
management and
operation
LEOSAR
First save during
demonstration and
evaluation phase
using first low Earth,
polar orbiting
weather satellites,
(e.g. POES)
1979
System developed
under Memorandum
of Understanding
(MOU) between
agencies from
Canada
France
USSR
USA
1982
1985
1988
System operational
under MOU between
DND (Canada)
CNES (France)
MORFLOT (USSR)
NOAA (USA)
MEOSAR
Development begins
of next generation
system based on
use of constellation
of mid Earth orbiting
GPS satellites
1996
2000
GEOSAR
System augmented
by geostationary
satellites (GEO)
(e.g. GOES)
More than 32,000 lives saved worldwide
NASA Search and Rescue Mission Office
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COSPAS–SARSAT System
•
•
•
•
•
•
•
Established by the United States, Canada, France and the former Soviet Union
43 participating countries and organizations
Current Operational
p
SAR p
payloads
y
on 12 LEO and GEO satellites
Worldwide network of 77 Local User Terminals providing data to 30 Mission Control
Centers
Over 1,000,000 emergency beacons in use worldwide
-
Aircraft: Emergency Locator Transmitter (ELT)
Ship: Emergency Position Indicating Radio Beacon (EPIRB)
Personal: Personal Locator Beacon (PLB)
System credited for ~32,000 lives saved
Much more information about the system and its use is available at
www.cospas-sarsat.org
COSPAS – SARSAT
participating countries
highlighted in green
NASA Search and Rescue Mission Office
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U.S. National SAR Structure
Interagency MOU in support of National Search and Rescue Committee
• Inland SAR
• Maritime
SAR
• Oversees
SAR Policy
y
• Research &
Development
NASA Search and Rescue Mission Office
• Operations
• CospasSarsat
liaison
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NASA SARSAT R&D
p
Accomplishments
• Developed every generation of COSPAS-SARSAT distress beacon location
system
– Developed original LEO (POES) beacon (Doppler) location technology (1970’s)
(1970 s)
– Developed GEO (GOES) space and ground segment
– Developed prototype ground and space segment for MEO (GPS) multiple satellite
detection and location
• Developed numerous beacon improvements
–
–
–
–
–
–
Improved beacon with 406 MHz digital transmissions
Self-locating beacons (GPS encoded location in 406 transmissions)
First beacon with digitally compensated oscillator
First beacon with highly efficient RF transmitter components
Personal Locator Beacon (PLB)
Proposed 2-way (return) message link
• Currently
C
studying improved transmission protocols designed to maximize
MEO system performance
– New technology development in beacons and signal processing receiver
equipment to work with prototype spread signal
– If adopted by international community would improve location accuracy, time of
receipt of beacon signal, capacity of beacon population, new capabilities, lower
costs
NASA Search and Rescue Mission Office
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Next Generation
MEOSAR
• Current space-based system is 30 years old and technological antiquated!
– LEO and GEO weather satellites (not 24/7 full earth coverage)
– Availability of satellites can delay beacon location 1-2 hours
– Store and forward payloads necessary
• In 2000 NASA, with DoD, DoE, NOAA, and USCG conducted a Proof-of-
Concept (POC) GPS demonstration called Distress Alerting Satellite System
(DASS) using GPS II R and F satellites (non-operational for COSPASSARSAT mission)
- POC paved the way for a proposed new operational system – SAR/GPS
to be interoperable among International Partners
- EU – SAR/GALILEO
- Russian – SAR/GLONASS
• 2009: USAF approved request from U.S. civil SAR community to host SAR
repeaters on 24 GPS-III
GPS III satellites
NASA Search and Rescue Mission Office
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SAR/GPS Overview
SAR/GPS
• GPS-III (future) satellites with 406 MHz repeater (civilian payload)
• Continuous global coverage provides more accurate location within minutes (single burst –
5 km, 5 min – 1km, 30 min – 100m)
• Repeater allows future compatibility with improved civilian and military beacons (overt and
covert signal processing)
• Minimizes signal blockage by terrain features
GPS Constellation
Downlink:
S–Band for POC
1544 MHz for OPS
SAR Aircraft
RCC
Uplink:
406 MHz
(C/S T.001 beacons)
NASA Search and Rescue Mission Office
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Prototype Ground Station
Four 4.27 meter antennas
Four
independent
receivers
Control and Display Console
Compatible with GPS, Galileo and GLONASS satellites
Data collected independently from each satellite (antenna)
Located at NASA Goddard Space Flight Center in Greenbelt, MD
NASA Search and Rescue Mission Office
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Pulse Signals – Current & Proposed
Current C/S Pulse
Spread Spectrum C/S Pulse
Relative Magn
nitude (dB)
Standard PLB
Receiver
R
i
Noise
N i
Floor
Spread Signal
Offset Frequency (kHz)
NASA Search and Rescue Mission Office
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Spread Spectrum Testing
•
•
A real time receiver capable off processing a spread spectrum signal in real time has been
developed and integrated into the NASA MEOLUT.
First test results presented here under following conditions:
–
–
–
–
–
–
Signal uses much less than full bandwidth – 25 KHz instead of eventual 80 KHz
Only three satellites used for location processing
Beacon burst transmitted every 4 seconds
Beacon transmitted at minimum power (2W, 32 dBm)
Location p
process not optimized
p
for highly
g y accurate TOA data
Spread spectrum signal characteristics not yet fully optimized.
NASA Search and Rescue Mission Office
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Single Burst Location Accuracy Results
•
Location Errors:
– Average
– Median
– StdDev
1.05 km
0.97km
0.55 km
1km
2km
5km
NASA Search and Rescue Mission Office
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Next R&D Steps
• Have prototype beacon and receiver to process Spread signal
- Still refining
g receiver to meet C/S 2nd g
generation requirements,
q
in particular 100 m accuracy within 30 minutes
• Collaborating with France and ESA to mature Spread Signal
technology
• Ready to perform field tests using GPS-II spacecraft
- Full end-to-end test: set beacon off,
bounce signal to on-orbit repeater back
to GSFC SARlab and then to a laptop
with 3-D imagery showing the beacon
signal location
NASA Search and Rescue Mission Office
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