Question 10

A carrier wave of peak voltage 15 V is used to transmit a message signal. Find the peak voltage of the modulating signal in order to have a modulation index of 60%.

Answer

It is given that peak voltage of carrier wave, A_{c} = 15V

and, Modulation index, m_{u} = 60% = 60/100

Then, peak voltage of the modulating signal (A_{m}) will be given by relation,

m_{u} = A_{m}/A_{c}

60/100 = A_{m}/15V

A_{m} = 60/100 x 15V

A_{m } = 9V

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