Solid medium: cable

Mixed Media: Optical Cable

Long wave, medium wave, short wave, ultra short wave

microwave

light wave

linear superposition interference

multiplicative interference

Binary Discrete Symmetric Channel BSC

Discrete Memoryless Channel DMC

Discrete input continuous output (transition probability of channel depends on noise)

Waveform channel (the input is an analog waveform, and the output is also an analog waveform)

If the input symmetry is satisfied and the output symmetry is satisfied, then H(Y|X)=H(Y|Xi) in the probability matrix (input equal probability distribution)

C=max{H(Y)-H(Y|X)}=max(H(Y)}-H(Y|Xi)=logs-H(Y|Xi) (the output is also equally likely to be distributed)

Only input symmetry is satisfied, but output symmetry is not satisfied

C=max{H(Y)-H(Y|X)}=max(H(Y)}-H(Y|Xi)=logs-H(Y|Xi) (both input and output are equally likely to be distributed)

The number of input and output symbols is the same (r=s); the diagonal of the transfer matrix represents the probability of correct transmission as (1-error probability), and the remaining equal probability distribution in each row (error probability/(s-1))

C=max{H(Y)-H(Y|X)}=max(H(Y)}-H(Y|Xi)=logs-H(1-error probability, error probability/(s-1), ..., error probability/(s-1)) (both input and output are equally likely to be distributed)