adc notes 2010 cs2204 subject notes

UNIT I FUNDAMENTALS OF ANALOG COMMUNICATION

UNIT II DIGITAL COMMUNICATIONINTRODUCTION:

FREQUENCY SHIFT KEYING:

UNIT III DIGITAL TRANSMISSIONINTRODUCTION:

Delta Modulation (DM) :

Delta Modulation (DM) :

The modulator consists of a comparator, a quantizer, and an accumulator. The output of the accumulator is

Differential Pulse-Code Modulation (DPCM):Usually PCM has the sampling rate higher than the Nyquist rate .The encode signal

contains redundant information. DPCM can efficiently remove this redundancy.

Figure 3.28 DPCM system. (a) Transmitter. (b) Receiver.

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