. What is Pulse Width Modulation (PWM).Explain
The width or duration of the pulses of the carrier pulse train is varied in accordance with the instantaneous value of the modulating signal. It is also called Pulse Duration Modulation (PDM). This is shown in figure. As is clear from pulse width or pulse duration of the original unmodulated carrier is constant. In the PWM or PDM as shown in figure the pulse width/duration is large, when the amplitude of the modulating sinusoidal signal is large and vice-versa. Thus in PWM or PDM, information about the baseband signal lies in the trailing edge of the pulse.