Compare AM with FM with respect to following points: a) Definition. b) Modulation index. c) Bandwidth. d) Side band.

1 Answer

Parameters
AM
FM
Definition
It is the process in which the amplitude of carrier signal is varied in accordance with the instantaneous value of modulating signal keeping frequency and phase constant.
It is the process in which the frequency of carrier signal is varied in accordance with the instantaneous value of modulating signal keeping amplitude and phase constant.
Modulation index
The value of modulating index is less than or equal to 1
The value of modulating index is always greater than 1 
Bandwidth
Twice the highest modulating frequency. 
Twice the sum of the modulating signal frequency and the frequency deviation.
Side band
There are two sidebands
Infinite number of sideband
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