Q7 of 8 Page 530

For an amplitude modulated wave, the maximum amplitude is found to be 10V while the minimum amplitude is found to be 2V. Determine the modulation index, μ. What would be the value of μ if the minimum amplitude is zero volt?

Maximum amplitude, Amax = 10 V


Minimum amplitude, Amin = 2 V


Modulation index μ is given by the relation:




⇒ μ = 8/12


∴ μ = 0.67


(b)


If Amin = 0


Then μ = Amax/Amax = 1


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