Pulse-amplitude modulation, acronym PAM, is a form of signal modulation where the message information is encoded in the amplitude of a series of signal pulses. It is an analog pulse modulation scheme in which the amplitude of train of carrier pulse are varied according to the sample value of the message signal.
Example: A two-bit modulator (PAM-4) will take two bits at a time and will map the signal amplitude to one of four possible levels, for example −3 volts, −1 volt, 1 volt, and 3 volts.
Demodulation is performed by detecting the amplitude level of the carrier at every symbol period.
Read more about Pulse-amplitude Modulation: Generation of PAM, Types, Use in Ethernet, Use in Photobiology, Use in Electronic Drivers For LED Lighting
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