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Media 可以承載的最大頻寬
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Nyquist理論 (沒有雜訊)
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D bps = 2 B log 2 K
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Shannon理論 (考慮雜訊)
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maximum number of bits/sec C = B log 2 (1 + S/N)
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| C | capacity (bps) | rate at which data can be communicated
| B
| bandwidth (Hz)
| the bandwidth of the transmitted signal as
constrained by the transmitter and the nature of the
transmission medium
| S/N
| Linear Signal-to-Noise Ratio
| |
|---|
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Evaluation of communication scheme performance
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How close to Shannon bound?
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Spectral efficiency (bit/s/Hz)
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