Question

The modulation index $\mu$ in amplitude modulating wave is :

• A. $\mu <1$
• B. $\mu >1$
• C. $\mu \ge 1$
• D. $\mu \le 1$

Answer 1

The correct option is D $\mu \le 1$

Modulation index is basically the ratio by which the modulated signal varies from the unmodulated signal and is given a percentage. The ideal index could be 100% which ensure a high signal to noise ratio in AM. a value higher than this would cause distertion by inclusion of side bands and a special circuit required at the receiver.

h=$\frac{\text{peak value of m(t)}}{A}$

=$\frac{M}{A}$

h=modulation index

M=Modulation Amplitude

A=carrier Amplitude