Question

For an amplitude modulated wave, the maximum amplitude is found to be 10 V while the minimum amplitude is 2.V. Calculate the modulation index. Why is modulation index generally kept less than one?

Answer 1

Here, A_max = 10V and A_min = 2 V

Modulation index = A_max -A_min/A_max +A_min = (10-2/10+2) = 8/12 = 0.67

Generally, the modulation index is kept less then one to avoid distortion.