University of Toronto – Connection 2006
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Fast Wideband Fast Wideband Electromagnetic Modeling of Electromagnetic Modeling of
Indoor Wireless ChannelsIndoor Wireless Channels
Abbas Alighanbari Abbas Alighanbari
Supervised by: Prof. Costas D. SarrisSupervised by: Prof. Costas D. Sarris
The Edward S. Rogers Sr. Department ofThe Edward S. Rogers Sr. Department ofElectrical and Computer EngineeringElectrical and Computer Engineering
University of TorontoUniversity of Toronto
University of Toronto – Connection 2006
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• Introduction:- Numerical Electromagnetics
• Methodologies: - High-order Time-Domain Techniques (S-MRTD v.s. FDTD)
• Applications to Wireless Communications: - Signal Fading Predictions
- Wideband Characteristics- Optimum Signal Transmission and Detection
• Future Work and Conclusions
OUTLINE
University of Toronto – Connection 2006
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Numerical ElectromagneticsNumerical ElectromagneticsNumerical ElectromagneticsNumerical Electromagnetics
Method of Moments and Finite Elements RF systems
wireless communications
EMC compliance
• Time-Domain: - Finite-Difference Time-Domain (FDTD)
- Multi-Resolution Time-Domain (MRTD)
• Frequency-Domain- Finite Element Method (FEM)
- Software: HFSS, FEMLAB
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MRTD vs FDTD : FormulationMRTD vs FDTD : Formulation
Spatial field expansion Spatial field expansion
F D T D F D T D
Galerkin method Galerkin method
Pulse basis Wavelet basis
Galerkin method Galerkin method
M R T D M R T D
Reference : Krumpholz et al, “A Field Theoretical Comparison of FDTD and TLM”, IEEE MTT-T, Sept. 1995
University of Toronto – Connection 2006
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Spatial Sampling FunctionsSpatial Sampling FunctionsSpatial Sampling FunctionsSpatial Sampling FunctionsOrder-7 Deslauriers-Dubuc Scaling Function
Smooth, Compact, Symmetric scaling functions
Deslauriers-DubucCoifman DaubechiesBattle-Lemmarie
High-order Families:
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ApplicationsApplicationsApplicationsApplications
• Microwave and Optical Circuits
- RF Circuits and Antenna Design
• Wireless Communications
- Mobile Communications
- Indoor Wireless Networks
- Ultra-Wideband Systems
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• Extremely narrow pulse width (less than 1ns)
•Low spectral power density ( Less than noise level)
• Low Interference to/from other wireless systems
• High speed multiple users
• High channel capacity
Ultra-Wideband Wireless
University of Toronto – Connection 2006
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• Introduction:- Numerical Electromagnetics
• Methodologies: - High-order Time-Domain Techniques (S-MRTD v.s. FDTD)
• Applications to Wireless Communications: - Accurate Signal Fading Predictions
- Wideband Characteristics and Channel Responses- Optimum Signal Transmission and Detection
• Future Work and Conclusions
OUTLINE
University of Toronto – Connection 2006
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Wideband Channel ModelingWideband Channel ModelingWideband Channel ModelingWideband Channel Modeling
P1
*
*
P2
Simulated Floor plan:
University of Toronto – Connection 2006
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Channel ResponsesChannel ResponsesChannel ResponsesChannel Responses
S-MRTD-5 : 3hrs/11min
S-MRTD-7.5: 11hrs/15min
FDTD-20: 4 days (92hrs/16min)
Receiving point P1
5/mindzdx : withMRTD-S
5.7/mindzdx: withMRTD-S
20/mindzdx : withFDTD
Receiving point P2
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Error-Time PerformanceError-Time PerformanceError-Time PerformanceError-Time Performance
4 times saving on: - CPU time - Cache Memory
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Signal Fading Profile Signal Fading Profile Signal Fading Profile Signal Fading Profile
Conductivity= 0.002 S/mRelative Permittivity = 3
FDTD-10 S-MRTD-5
Sinusoidal steady state
12 hrs/44min52 hrs/36min
University of Toronto – Connection 2006
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Signal Fading ProfileSignal Fading Profile Signal Fading ProfileSignal Fading Profile
Conductivity= 0.05 S/mRelative Permittivity = 3
FDTD-10 S-MRTD-5
Sinusoidal steady state
12 hrs/44min52 hrs/36min
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Signal Attenuation (Fading)Signal Attenuation (Fading)Signal Attenuation (Fading)Signal Attenuation (Fading)
LOS
NLOS
LOS
NLOS
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Power Profile 2Power Profile 2Power Profile 2Power Profile 2
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Wall Attenuation and Guiding Effects Wall Attenuation and Guiding Effects Wall Attenuation and Guiding Effects Wall Attenuation and Guiding Effects
010
010 10ˆ
ˆ10
d
dnLog
p
pLog
Path Loss Exponent (PLE)
University of Toronto – Connection 2006
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Fading Statistics - Rayleigh ModelFading Statistics - Rayleigh ModelFading Statistics - Rayleigh ModelFading Statistics - Rayleigh Model
Cumulative Density Functions
NLOS points 0)(r rr
rp
,2
exp)(2
2
2 σ= rms value of the received signal
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ConclusionsConclusionsConclusionsConclusions
• Performance Analysis and Applications of S-MRTD
• The application of S-MRTD to Wireless Channel Modeling
• Fading and Statistical Properties
• Optimized Signal Transmission and Detection
University of Toronto – Connection 2006
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Future WorkFuture WorkFuture WorkFuture Work
• Investigation of Antenna Patterns in Smart Antenna Applications
• Adaptive Mesh Refinement
• 3D Modeling of Wireless Channels
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Thank you !
Questions/Remarks ?Questions/Remarks ? Questions/Remarks ?Questions/Remarks ?
