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pulse-code modulation

American  
[puhls-kohd] / ˈpʌlsˌkoʊd /

noun

Telecommunications.
  1. a form of modulation that transforms a wave-form, as an audio signal, into a binary signal in which information is conveyed by a coded order of pulses for transmission, storage on a disk, or processing by a computer. PCM


pulse code modulation British  

noun

  1.  pcmelectronics a form of pulse modulation in which the information is carried by coded groups of pulses

"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

Etymology

Origin of pulse-code modulation

First recorded in 1945–50