A carrier wave of peak voltage 24 V is used to transmit a message signal. What should be the peak Voltage of the modulating signal in order to have a modulation index of 70%?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 16.8V
The modulation index (m) for amplitude modulation (AM) is given by -
$m=\frac{V_m}{V_c}$
where,
$V_m$ = Peak voltage of modulating signal
$V_c$ = Peak voltage of carrier signal
$V_m=24V$ [given]
$m=70\%=0.70$ [given]
$V_m=m.V_c$
$=(0.70×24)V$
$=16.8V$