CP3 Workshop Wideband Systems 18 June 2005

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CP3 WorkshopWideband Systems18 June 2005
UNCLASSIFIED

• William Prather
• HPM Technologies Branch
• AFRL/DEHP

UNCLASSIFIED
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Wideband vs. Ultra-Wideband HPM
Wideband
Ultra-Wideband
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Why Wideband?

• Measured Transfer Function for Coupling to a
  Typical System
• Low Frequencies Couple Most Effectively

Narrowband
Wideband
Ultra-wideband
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H-2 UWB Source

• Waveforms Typical of
• H-2, H-5
• Phoenix
• Thor (Navy)

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HPM Comparison

• Narrowband
• Electron beam tube technology
• Typically 900-1300 MHz
• Good power at a distance
• Advantages
• High Power at a distance
• Disadvantages
• Very narrow bandwidth
• Higher frequencies on (gt900 MHz)
• Single shot or very low PRF
• Weight, size, vacuum volume
• High power from single tube breakdown problems

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HPM Comparison

• Wideband
• High voltage switching technology (150 kV-1MV)
• 100-900MHz Damped Sine Wave (10 BW)
• Advantages
• High coupling to target, better penetration
  through walls, foliage
• 10 bandwidth ? less effected by target variation
• Disadvantages
• Long wavelength requires larger antenna for high
  gain
• Typically less range than NB

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HPM Comparison (Continued)

• Ultra-Wideband Sources
• Advantages
• Fast transient waveform
• 2 decades of BW
• Useful for target identification radar (PING)
• Disadvantages
• Low spectral density
• Leff effective for upset of electronics
• Require large, UWB antennas

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History

• 1990-1995 Developed WB and UWB Technology
• H-2 and Phoenix
• IRA I
• Effective, but needed waveform optimized
• 1995-1997
• H-5 Source, like H-2
• Jolt Source (UWB)
• 1997- 1999 China Lake
• Navy THOR
• IRA II
• 1999- Present
• MATRIX Source, WB
• Compact Source, WB
• Compact resonant Blumleins, WB
• Compact Marx generators

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Wideband Systems
Pulse Power
Prime Power
PFN
Antenna
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WIDEBAND RF PROGRAM
Basic Research Tech Dev
Applications
Basic Research Technology Dev
Applications

• Sources
• Tunable WB Source
• WB Array
• UWB Transient Source
• Modeling Simulation
• Trade Studies
• Target Response
• Platform Integration
• Feature Extraction
• Noise Reduction
• Clutter Penetration
• Identification

• Antenna Concepts
• EM Theory
• Propagation, Scattering
• Interaction Coupling
• Target ID Theory
• Precision Switching
• Solid State
• Gas
• Dielectrics
• High Voltage Insulation
• Lenses
• Artificial Dielectrics

• Target ID System
• Concealed Weapons
• Targets Under Trees
• Land mines
• C2W
• Airborne Source
• Munition
• Compact Source
• Intelligence
• Wideband Receive

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BASIC RESEARCH AFOSR Current Programs

• Carl Baum
• Electromagnetic Theory
• Target ID Theory
• WB Source Concepts
• Antenna/Mode Convertor Concepts
• Jeff Heggemeier
• Target ID Algorithms
• Noise/clutter
• Grekhov St Petersburg
• SiC Switches Electrically triggered
• U Missouri
• SiC Switches -- Laser triggered

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SMALL BUSINESS INNOVATIVE RESEARCH
(SBIR) Current Contracts

• Solid State Switching Technology
• Time Domain Corp
• Pulse Systems Group (Sysoev)
• High PRF Marx
• Tunable Mismatched Blumleins
• Conformal Wideband Antennas
• High Speed Digitizers

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Critical Wideband Technology Areas

• Antennas
• Wideband and UWB
• Sources/Pulse Power
• Compact
• New Switch technology
• Materials
• Modeling
• Air breakdown
• Rep rate
• Lifetime
• Prime Power
• Power supplies
• Batteries
• Other
• UWB T/R Switch
• Dir Cplr Limiter

• Target ID
• RF/HPM Effects
• Revolutionary Tech
• Compact Sources
• UWB Comm
• Rescue beacons

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Future Wideband Efforts

• Sources
• Higher Voltage
• Higher Rep Rates
• Tunability
• Refine Effects Assessment Methodology
• Optimize Waveforms
• Increase Effects Data Base

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Wideband Technology

• Pulsed Power
• Compact Marx
• Resonant Transformer
• PFNs
• Mismatched Blumleins
• LCO
• ¼ ? Shorted Transmission Line (Matrix)
• Pulse Compression Schemes

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Wideband Technology Needs

• Compact, High Power Sources
• Greater energy density
• High voltage
• Tunable
• Higher PRF
• Low Jitter to allow arraying

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Wideband Technology Needs

• Antennas
• Wideband and UWB
• Conformal
• Compact
• Arrays

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H-2 Source for Material Experiments

• The H-2 system has been returned to a reliable
  and safe operating state
• The mechanical safety factor was improved from
  1.0 to 4.0 for long term operation
• Recommended peak transformer output voltage of
  280 kV, but can be operate up to 460 kV
• System is ready for material experiments

Mechanical stresses in revised H2 design
E-Field magnitude plot for the revised H2 design
(kV/cm)