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8/14/2019 DIGITAL COMMUNICATION UNIT 1 GCT
1/46
PULSE CODE MODULATION (PCM)
Pulse code modulation (PCM) is producedby analog-to-digital conversion process.
As in the case of other pulse modulationtechniques, the rate at which samples aretaken and encoded must conform to theNyquist sampling rate.
The sampling rate must be greater than,twice the highest frequency in the analogsignal,
fs > 2fA(max) 1
DIGITALC
OMMUNIC
ATION-UN
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8/14/2019 DIGITAL COMMUNICATION UNIT 1 GCT
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3.6 Quantization Process
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