Lecture 3: Characteristics of Wireless Medium

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(No Transcript)
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Performance in one location

• Multipath Fading causes variations on the data
  rate
• Shadow fading causes variations in average data
  rate
• How should we evaluate the performance?

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Performance in an area
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Performance comparison
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Lab Performance and Channel Model

• Why not just coverage performs?
• It is labor extensive
• Tests can not be repeated thoroughly again
• What is needed for laboratory test?
• Expensive measurement equipment
• Accurate channel models
• Expensive real-time channel simulators
• Who is doing the channel modeling?
• IEEE 802.11 for MIMO
• IEEE 802.15 for UWB
• DARPA for indoor positioning

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Multipath measurement
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Ray Tracing for Multipath Simulation
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Whats the difference for MIMO?
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IEEE 802.11 Model for MIMO
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Whats the difference for UWB?
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Whats the IEEE 802.15 model?
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What is the difference for positioning?
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Accurate positioning needs TOA
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What do we do with models?
Measurements
Ray Tracing
Statistical Models
Real Time Channel Simulator PROPSIM
Prototype Modem
Prototype Modem
Interference
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PROPSim Hardware Channel Simulator