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Harbin Institute of Technology (Weihai) 1 Chapter 3 Channel Modeling Large-scale effects Small-scale effects Undesired signals (noise and interfering signals)
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Harbin Institute of Technology (Weihai) 2 3.3 Large-Scale Channel Modeling The signal attenuation with distance (Path Loss) 3.3.1 Free-space path loss modeling: the Friis Transmission Formula( 功率传播方程 ) Flux density( 流量密度 )
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7 Conclusion: The path loss, or more accurately the spreading loss, in free-space is not frequency dependent.
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10 3.3.2 Path Loss Modeling for Non-Free-Space Environments Average Path Loss of a Narrow band system For UWB, n is almost constant with frequency.
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Harbin Institute of Technology (Weihai) 12 Small-scale channel modeling Include the small-scale fading in a local environment as well as the distortion of the transmitted waveform due to multipath. Statistical modeling needed for proper receiver design. (evaluation of the receiver, diversity mechanisms, and potential multiple antenna applications)
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Harbin Institute of Technology (Weihai) 13 Statistical modeling of the channel impulse response
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Harbin Institute of Technology (Weihai) 14 Saleh-Valenzuela Model L is the number of paths per cluster and K is the number of clusters. The basic assumption behind this model is that the multipath components arrive in clusters. The cluster arrivals are described by a Poisson process.
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Harbin Institute of Technology (Weihai) 15 Other models Delta-K model Single Poisson model Modified Poisson model Split-Poisson model
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Harbin Institute of Technology (Weihai) 16 Chapter4 Antennas
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Harbin Institute of Technology (Weihai) 17 Resonant monopole
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Harbin Institute of Technology (Weihai) 20 Archimedean Spiral- a frequency independent antenna
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Harbin Institute of Technology (Weihai) 23 TEM Horn- a UWB antenna
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Harbin Institute of Technology (Weihai) 26 summary
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