Define pulse modulation. State its types.

Define pulse modulation. State its types. 
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2 Answers

Answer :

Pulse Modulation: It is defined as the modulation technique in which the various parameters of carrier signal which is the train of periodic rectangular pulses changes in accordance with the instantaneous value of modulating signal.

Types of Pulse Modulation:

Analog Pulse modulation 

PAM

PWM

PPM

Digital Pulse Modulation 

PCM

DM

ADM
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Answer :

Pulse Modulation - consists essentially of sampling analog information signals and then converting those samples into discrete pulses. OR It consists essentially of sampling analog information signals and then converting those samples into discrete pulses and transporting the pulses from a source to a destination over a physical transmission medium. OR Pulse modulation is a technique in which continuous waveforms are sampled at regular intervals. i.e. carrier is a train of discrete pulses. 

Types:- i) Analog Pulse modulation - PAM - PWM – PPM

 ii) Digital Pulse Modulation - PCM - DM – ADM 
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