Shannon Channel CapacityMutual Information · Noisy Channel Theorem

Channel Parameters

AWGN Cap (bps)
BSC Cap (bits)
I(X;Y) bits
H(X) bits
Shannon-Hartley: C = B·log₂(1+S/N)
BSC capacity: C = 1 − H_b(ε)
where H_b(ε) = −ε log₂ε − (1−ε)log₂(1−ε)

Mutual information:
I(X;Y) = H(X) − H(X|Y)
= Σ p(x,y) log₂[p(x,y)/p(x)p(y)]

Capacity = max over input distributions p(X).