Pulse Code Modulation (PCM) is a digital representation of an analog signal. The signal is sampled at a sampling frequency f
s. This means the value of the signal, a sample, is captured at uniform distances T (= 1/f
s). Every sample is quantised to a discrete number of possible values.
PCM is used in digital telephone systems or for digital audio recording on compact discs CD.
See modulation for other examples of modulation techniques.
/Talk