Define modulation index. Why is it generally kept less than one ?

Explanation

(i) Mosulation index : The degree to which the carrier wave is modulated, is called madulation index. It is given by
`m=A-m/A_i`
Where `A_m` is the amplitude of modulated wave and `A_c` is the amplitude of carrier wave.
(ii) The amplitude of modulating signal is less than the amplitude of carrier wave. Detection is the process of recovering the modulating signal from the modulated carrier wave.