radio transmission in which the carrier wave is modulated by changing its phase to transmit the amplitude and pitch of the signal.
Origin of phase modulation
First recorded in 1925–30
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a type of modulation, used in communication systems, in which the phase of a radio carrier wave is varied by an amount proportional to the instantaneous amplitude of the modulating signal
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
A method of transmitting signals in which the value of the signal is proportional to the phase angle of a carrier wave. It is often combined with amplitude modulation to transmit digital information via modems.
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