Overview of Electromagnetics Research

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Overview of Electromagnetics Research

• Weng Cho Chew
• Director, Center for Computational
  Electromagnetics
• Department of Electrical and Computer
  EngineeringUniversity of IllinoisUrbana, IL
  61801USA
• Deans Visit
• August 21, 2001

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Faculty in the EM Area

• Jennifer Bernhard
• Wireless antennas
• Andreas Cangellaris
• EM for circuits
• Weng Chew
• CEM (computational EM), fast algorithms, inverse
  scattering
• Shun-Lien Chuang
• Optics, lasers
• Jianming Jin
• CEM, bioelectromagnetics, finite elements
• Eric Michielssen
• CEM, fast time-domain solvers, genetic algorithms
• Jose Schutt-Aine
• EM for circuits, computer clusters, computer
  visulization

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Areas of Research

• Computational electromagnetics
• Fast algorithms
• Inverse scattering and imaging
• Genetic algorithms
• Computer chip simulation
• Antennas, reconfigurable antennas
• Wireless communication
• Bioelectromagnetics
• Subsurface sensing, remote sensing
• Radar cross section
• Electromagnetic compatibility/electromagnetic
  interference
• Optoelectronics and lasers
• Computer visualization

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IMPACT OF ELECTROMAGNETICS
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VFY218 at 3 GHz (W. Chew)
Bistatic RCS of VFY218 at 3 GHz 8 processors of
SGI Origin 2000 of Unknowns N 2 millions
5 0.1
9 32,000 600.0 200 4 32,000
600.0 500
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83 Camaro at 1 GHz by FISC (W. Chew)

• Irradiation of a 83 Camaro at 1 GHz by a Hertzian
  dipole.

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3D Layered Medium Problems - Numerical Results
(W. Chew)

• Underground Bunker

f 300MHz N 100,314 6 level ML-FIPWA
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Luneburg Lens Scattering (J. Jin)
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Inlet Scattering (J. Jin)
Simulation
Measurement
2,000,000 unknowns
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Corrugated Horn Antenna (J. Jin)
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Corporate-Fed Antenna Array (J. Jin)
Radiation patterns
Current distribution
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EM Interaction (J. Jin)
Magnetic field
SAR at 171 MHz
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EM VFY218 Current distribution (snapshots in
time) (E. Michielssen)

• .

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Broadband Analysis of Wave Interactions with
Nonlinear Electronic Circuitry
PWTD solvers permit analysis of wave broadband
EMC/EMI phenomena, and the assessment of
electronic upset and terrorism scenarios
20 cm
10 cm
5 cm
1 cm
17.5 cm
Voltages on the varistors
0.5 cm
6 cm
4.5 cm
25 cm
25 cm
Voltage (kV)
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Broadband Analysis of Antennas, Scattering, and
Radiation Phenomena
PWTD solvers are used to fully characterize a
25-88 MHz log-periodic monopole array mounted on
a C-12 aircraft. The array serves in foilage
penetration radar studies.
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Reconfigurable Antennas for Wireless
Communication(Jennifer Bernhard)

• Planar and microstrip antenna development
• Reconfigurable in frequency, bandwidth, and/or
  radiation pattern
• Linear and circular polarization
• Patch, spiral, sinuous
• For applications in
• Planar phased arrays and reflectarrays
• Single element wireless communication
  implementations

Courtesy NASA GRC
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Advanced Electromagnetic Modeling of Mixed-Signal
Systems (A. Cangellaris)

• Objective
• Establish a comprehensive modeling capability
  with electromagnetic accuracy and simulation
  efficiency necessary for virtual prototyping of
  multi-functional, mixed-signal, multi-GHz
  (digital/RF/microwave/opto -electronic)
  integrated systems
• Impact
• Global modeling and simulation environment that
  comprehends the temporal and spatial multi-scale
  features of mixed-signal, multi-GHz, integrated
  electronic subsystems and systems
• Comprehensive electromagnetic modeling at the
  chip, package, board and system level
• Enable a universal computer-aided design
  environment for multi-physics (electrical,
  optical, thermal, mechanical) modeling
  simulation aimed at the virtual prototyping of
  tomorrows integrated systems

A.C. Cangellaris Research Group Modeling from
dc to light!
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Advanced Electromagnetic Modeling of Mixed-Signal
Systems (A. Cangellaris)

• Specific Research Tasks
• Electromagnetic (EM) modeling of on- and off-chip
  electronic and optical interconnects
• EM modeling of passive digital/RF/microwave
  signal processing components (filters, couplers,
  power dividers, etc.) integrated in a 3-D
  substrate
• Comprehensive modeling of power distribution
  networks for mixed-signal systems
• Behavioral modeling of non-linear digital,
  analog/RF, and optical devices
• Methodologies for EM complexity abstraction and
  model order reduction that lead to compact and
  accurate macro-models for complex EM and
  opto-electronic devices and functional blocks
• Methodologies for the incorporation of EM
  macro-models in a universal, state space- based,
  non-linear simulation environment
• Sponsors
• DARPA (Automated Design Tools for Integrated
  Mixed-Signal Microsystems-NEOCAD)
• Intel, Motorola, IBM, Texas Instruments,
  Semiconductor Research Corporation
• NSF
• Army Research Office (MURI Program on
  Quasi-Optical Power Combining Systems)

A.C. Cangellaris Research Group Modeling from
dc to light!
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Optical Communication (S. Chuang)

• The exploding demand for Internet access,
  telecommunications, and broadband services has
  led to a push for greater lightwave transmission
  capacity.
• Optical fiber networks now carry a large amount
  of voice and data traffic all over the world.
• Improving the high-speed performance of
  semiconductor lasers benefits the
  telecommunication industry and society.

Modulated optical signal
Laser
Photodetector
Fiber cable
(Installed on land, under the ocean, and in the
walls of buildings)
Electrical data source
Electrical data recovered
Location 1
Transmitter
Receiver
Location 2
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Four-channel Wavelength Division Multiplexing
(WDM) integrated laser source (S. Chuang)

• This device consists of four wavelength-tunable
  three-electrode DFB lasers which are coupled into
  a single waveguide, optical amplifier, and
  modulator.
• Professor S. L. Chuangs group conducts research
  on high-speed semiconductor optoelectronic
  devices, fiber optics, and optical transmission
  characteristics. Both theory and experiment are
  researched.

Optical amplifier
s-bends
Star coupler
Electroabsorption
Distributed-
feedback
modulator
lasers