Back The information‑carrying capacity of a communications system is directly proportional to the bandwidth of the signals it carries. The greater the bandwidth, the greater the information‑carrying capacity. An important parameter for determining the capacity of a channel is the signal‑to‑noise ratio (SNR). This is normally defined, in decibels, as:

\(S/N(dB)= \log_{10}\frac{S}{N}\)

In a digital system, Nyquist predicted that the maximum capacity, in bits/sec, of a channel subject to noise is given by:

\(C= B.\log_{2}(1+S/N)\)