(a) What is amplitude modulation? Draw a diagram showing an amplitude modulated wave obtained by modulation of a carrier sinusoidal wave on a modulating signal.
(b) Define the terms (i) modulation index, and (ii) side bands. Mention the significance of side bands.

Explanation

(b) (i) Modulation Index :
(ii) Side Bands : Side band is the portion of a modulated carrier wave that is either above or below the base band signal. `(w_(1)-w_(m))` is the lower side band `(w_(1)+w_(m))` is called the upper side band. Both side bands are used to carry a message.