(a) Explain amplitude modulation of a sinusoidal carrier wave using a modulating signal, with the help of necessary diagrams.
(b) For a given amplitude modulated wave, the maximum amplitude is 20V and minimum amplitude is 5V. Calculate the modulation index.
Amplitude modulation is the process of varying the magnitude of a carrier wave in accordance with respect to the instantaneous variation of the signal that is audio frequency signal.
Audio frequency signal
fs = frequency of signal
For amplitude modulated wave
(B) Given,
the maximum amplitude of the wave,
minimum amplitude of the wave,
We know that,
modulation index,
hence the modulation index of given amplitude wave is 0.6.