Multifunction Phased Array Radar

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MultifunctionPhased Array Radar
3rd National Surface Transportation Weather
Symposium 26 July 2007 Colonel Mike
Babcock Deputy Director of Weather for Federal
Programs HQ US Air Force
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Overview

• What is phased array radar?
• Why Multifunction Phased Array Radar (MPAR)?
• Potential Benefits
• Surface Transportation Applications
• MPAR Working Group and Way Ahead
• Summary

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What is Phased Array Radar?
Planar phase front
Electronically added phase delay
Mechanically Steered, Rotating Reflector
Electronically Steered, Fixed Phased Array
VS
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RF Solid-State T/R Module Trends
Cost
Estimated Production Cost (K) per module
Power
System costs substantially reduced operation
costs lower every year
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MPAR Origin

• In FY 2000 Congress mandated research and
  development of phased array radar technology to
  improve aircraft tracking and weather information
  for civilian use (Tri-Agency FAA, NOAA, DOD)
• NRC report Beyond NEXRAD (2002), recommends PAR
  technology be developed as replacement for legacy
  weather radars
• In 2004 Federal Committee for Meteorological
  Services and Supporting Research (FCMSSR)
  directed an interagency Joint Action Group be
  convened to assess RD priorities for MPAR

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MPAR Technology Motivation
Federal Research and Development Needs and
Priorities for PAR (2006) FCMSSR Joint Action
Group
Beyond NEXRAD (2002) National Research Council
National Weather Radar Testbed (2005)Norman, OK
http//www.ofcm.gov/r25-mpar/fcm-r25.htm
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MPAR Programmatic Motivation

• MPAR can enable a 35 reduction in the number of
  radars needed to provide the current domestic
  weather and aircraft surveillance coverage
• MPAR can save 1.8 billion in replacement
  acquisition costs
• MPAR can save an additional 3 billion in life
  cycle costs over 30 years

PLUS
PLUS
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MPAR Approach
Today
Single System
Seven System Types
Multi-Mission
Single Mission
Non-Scalable
Scalable to Mission Needs
Consolidated Maintenance,Logistic and Training
Prgms
Multiple Maintenance, Logistic and Training
Prgms
Mechanically Rotating
Electronically Steered
5000 ft AGL, Blue, weather only
Future Concept
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Potential Benefits

• Weather sensing
• Rapid temporal sampling full volume scan periods
  lt 1 minute
• Adaptive antenna tilts reduce ground clutter
• Adaptive dwell times/beam steering selective
  target revisit in seconds rather than minutes
• Split aperture correlation to estimate crossbeam
  wind component
• Dual polarization for hydrometeor discrimination
• Increases safety and capacity in severe weather
  conditions
• Increased lead time for tornado warnings
• Increased lead time for flood and severe weather
  warnings
• Improved initialization of numerical weather
  prediction models leading to improved forecasts
• Support for research on other severe storm
  phenomena

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Potential Benefits (continued)

• Aviation Terminal Enroute surveillance
• Significant reduction in false track probability
• Vertical position measurement
• Dedicated track modes
• Sub-second track update rates in terminal area
• Hazardous weather monitoring
• Homeland security
• Non-cooperative air target tracking
• Wind field mapping for dispersion models
• Nuclear biological chemical (NBC) trackingRD
  needed
• Volcanic ash, airborne debris

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Surface Transportation
Major Weather Impacts
Roadways
Precipitation
Railroad
Winds
Transit
Visibility
Pipeline
TemperatureVariation
Models Forecasts
Maritime
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New paradigms

• A future with MPAR
• Wide deployment to match or exceed todays
  coverage, and possibly smaller systems to fill
  gaps
• Potential major economies and efficiencies
• Collaborative Adaptive Sensing of the Atmosphere
  (CASA)
• Ubiquitous smaller radars on cell towersfill
  gaps and provide higher resolution coverage in
  the atmospheric boundary layer
• Natural emphasis on key surface transportation
  activities

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MPAR Working Group

• Recommendation 3 from JAG report Working Group
• Identify agency contributions to risk reduction
• Establish cost basis for near-term agency
  contributions, sufficient to support budget
  development
• Explore options to foster interagency cooperation
  and collaboration on risk reduction activities
• Develop specific program progress metrics
• Prepare/publish annual report on progress and
  next-year objectives and activities
• Identify opportunities for review by appropriate
  boards and committees of the National Research
  Council
• Prepare/publish an education and outreach plan
• Recommendation 4 from JAG report
• Undertake a cost-benefit analysis

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Current MPAR WG Activities

• Developing a joint Concept of Operations (CONOPS)
  for MPAR
• Collecting, developing, and analyzing agency
  operational requirements (driven by CONOPS)
• Continuing technology research program initiated
  with MIT/LL
• Evaluating affordability, performance and
  multifunctional capability
• Developing preliminary architecture and design
  for MPAR, including cost model
• Initiating NRC Board on Atmospheric Sciences and
  Climate (BASC) study to assess methodology and
  cost estimates

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Future Efforts

• Continue to assess development of low cost,
  critical component technologies
• Transmit/receive modules
• Focus on additional MPAR research
• Continue exploring improved solid state
  technologies
• Continue research to improve multiple
  missions/functions
• Solidify key technical requirements for objective
  system
• Number of independent channels
• Number of concurrent beams per channel

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Future Efforts (continued)

• Develop a technology demonstration program
• Analyze critical technologies
• Develop a pre-prototype
• Develop full MPAR prototype
• Demonstrate affordability
• Test MPAR in an operational environment

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Summary

• Phased array offers significant benefits and
  costs are coming down
• Faster scans, higher resolution, dwell time,
  multifunction capabilitytransportation
  advantages
• Learning from National Weather Radar Testbed
• Potential 5B savings over life cycle
• Interagency effort to reduce risk, draft Concept
  of Operations, define requirements, refine
  cost-benefit analysis BASC study--validation
• Push technology, solidify technical requirements
  and demonstrate capability and affordability

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Questions
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BACKUP SLIDES
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Phased Array Radar Evolution
1991
1989
1992
2000
1996
1997
1993
1994
1995
1990
1998
1999
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Phased Array Radar Evolution (continued)
2002
2000
2003
2007 2008 and beyond
2004
2005
2006
2001
2001-2005 Natl Wx Radar Testbed
2006 - 2010 MPAR Pre-Prototype
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National Weather Radar Testbed
National Severe Storms Laboratory Norman, Oklahoma
BACKUP SLIDES
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MPAR vs. NEXRAD Scan Rate Microburst Event

• MPAR captures 29 clear images and more data
  during the time it takes NEXRAD for 4, the result
  is better forecasts and earlier warnings

MPAR
Strong updraft indicated by weak echo region
Rapid descent of high reflectivity core
NEXRAD
194005
194457
MPAR
Strong outflow at 195600
Weak outflow in corresponding velocity field at
195103
NEXRAD
194949
195442
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MPAR Pre-Prototype Demo System
4.2 m
16 Subarray Phase Centers
4.2 m
Subarray

• Pre-Prototype radar demonstrates two simultaneous
  modes
• Beamwidth 2º az by 2º el (broadside)
• Two independent beam clusters
• Electronic steering 45º az, 40º el
• Up to 8 beams in each 1D cluster
• Provides terminal area coverage to 210 km
• _at_10 W per element

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MPAR Pre-prototype Development Schedule
Year 1 Year 2
Year 3 Year 4
CDR
PDR
Testing CDR
Concept Development, Design, and Subsystem
Prototyping
System Fabrication and Assembly
Experimental Testing and Evaluation
Brick
Sub array
Array
Data Collection

• 16 Element Brick
• Transceiver
• Waveform Design
• Systems Analysis

• 80 Element Sub array
• DBF Dev
• Algorithm Dev
• System Simulation

• 4544 Element Array
• 16 Channel DBF
• System Simulation
• Test Planning

• Collect Multimode Data
• Process Data
• Report Results

Hardware
Systems Signal Processing
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Technology Advancements

• Leverage research in semiconductors for PAR
• Increased power density
• Increased power efficiency
• Improved thermal management
• Leverage Defense Advanced Research Projects
  Agency (DARPA) wide bandgap Gallium Nitride (GaN)
  effort
• Awards Total 144.5M over five years (began in
  March 2005)
• Wide bandgap semiconductor (WBGS) for radar
  application
• Q band Solid State Power Amplifiers(Northrop
  Grumman/Emcore)
• X band T/R module (Raytheon/Cree)
• Wide band High Power Amplifier (Lockheed
  Martin/TriQuint)

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S-band Power Amp Cost by Output Power
Packaged ICs in 2 - 3 GHz Band
Manufacturers APT Analog Devices Cree Eudyna Hitti
te Infineon Motorola M/A Com RF
MicroDevices Triquint
LDMOS
GaAs MESFET
GaAs/InGaP HBT
SiGe HBT
Si BJT
IC cost dominates
Package cost dominates

• Optimal choice of HPA cost vs power is in 1W
  10W range

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T/R Module Designs
SMALLER, HIGHER POWER, MORE EFFICIENCY
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MPAR Development Timeline
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U.S. Surveillance Radar Networks Today
NEXRADs