Using FEKO for Electromagnetic Simulations in the...
Transcript of Using FEKO for Electromagnetic Simulations in the...
Copyright © 2008 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
Using FEKO for Electromagnetic
Simulations in the Automotive Environment
Dr. Ulrich Jakobus
EM Software & Systems
www.emss.de / www.feko.info
Copyright © 2008 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
Contents
Introduction
• Electromagnetic environment
Computational methods
• Overview
Application Examples
Summary and Conclusion
Copyright © 2008 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
Introduction
Antenna analysis in complex environments.
Copyright © 2008 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
3D EM Simulation Map
Complexity of Materials
Electrical Size
Copyright © 2008 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
3D EM Simulation Map
Complexity of Materials
UTD
PO/GO
MOM
FEM
MLFMM
Electrical Size
Copyright © 2008 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
Analysis of vehicle-mounted antennas
Fender antenna for VW Beetle
Creation of a computational model
Details that can be included:• Transition resistances at hinges and
door locks
• Lossy dielectric ground (wet, dry)
• Plastic parts (e.g. bumper, seat)
• Glass windscreen
CAD model
Mesh
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Analysis of vehicle-mounted antennas
Surface current distribution
Horizontalfar-fieldpattern
• Fender antenna for VW Beetle• Transmitting case (same patter as
receiving due to reciprocity)
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Analysis of vehicle-mounted antennas
MeasurementComputation
• Rod antenna at 100 MHz
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Analysis of vehicle-mounted antennas
GPS Antenna
Radiation Pattern
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Analysis of vehicle-mounted antennas
GPS Antenna
Radiation Pattern
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Effect of Conducting Windows
Conductive layer for thermal protection
Effect modelled using thin dielectric sheet
formulation
Far Field Gain vs Angle
Phi [Deg] at Theta = 90.00 [Deg]
With windows No Windows
0º 345º330º
315º
300º
285º
270º
255º
240º
225º
210º195º180º165º
150º
135º
120º
105º
90º
75º
60º
45º
30º15º 0º
0
-2
-4
-6
-8
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ICNIRP Compliance for TETRA Radio System
Low current density
High current density
Maximum localised SAR
High E-field values
Low E-field values
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Tire Pressure Sensor Radiation Analysis
Front tire antenna excitation Rear tire antenna excitation
Opposite side -53.8 dBV/m
True side -49.7 dBV/m
Opposite side -61 dBV/m
True side -55 dBV/m
Y. Yamada, K. Tanoshita, K. Nakatani, S. Horiuchi, “FEKO Simulations and Measurements of Electrical Field Distributions around a Car,” ACES 2007, Verona, Italy, March 2007
Copyright © 2008 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
Optical Controller
Spectrum Analyser
Field Distributions Inside a Vehicle - Verification
Measured
Simulated
Y. Yamada, K. Tanoshita, K. Nakatani, S. Horiuchi, “FEKO Simulations and Measurements of Electrical Field Distributions around a Car,” ACES 2007, Verona, Italy, March 2007
Copyright © 2008 Altair Engineering, Inc. Proprietary and Confidential. All rights reserved.
EMC Coupling Problem (Exhaust Pipe)
Coupling between engine area and
the receiving antenna at the rear of
vehicle (resonance on exhaust at 24 MHz).
f = 24 MHz
f = 27 MHz
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Aircraft Antenna Placement: Validation
M. V. T. Heckler* and A. Dreher,
Analysis of Monopoles Installed on
Airframes, 2005 IEEE APS
Symposium, Washington DC, July 2005
VHF Com Antennas – 126MHz
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Aircraft Antenna Placement: Validation
Air Traffic Control Antenna at 1GHz λ/5 Mesh with 193,212 trianglesMoM/PO Hybrid Technique
Measurements – 1/12th scale model
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Aircraft Antenna Placement: Validation
Air Traffic Control Antenna at 1GHz
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Summary and Conclusion
Introduction• Antenna Design
• Electromagnetic Environment
Computational methods• Overview
Application Examples• Different Antennas
• Tyre Pressure System
• EMC Applications