A sinusoidal carrier voltage is amplitude modulated. The resultant amplitude modulated wave has maximum and minimum amplitude of 120 V and 80 V respectively. The amplitude of each sideband is :

Question

A sinusoidal carrier voltage is amplitude modulated. The resultant amplitude modulated wave has maximum and minimum amplitude of 120 V and 80 V respectively. The amplitude of each sideband is : (A) 10 V (B) 5 V (C) 20 V (D) 15 V

Tardigrade Admin · Accepted Answer

A c + A m =120 Ac-Am=80 ∴ overline A c =100 Am=20 Modulation index =(20/100)=(1/5) Amplitude of each sideband = A c (( text mod ulation index )/2) =100 × (1/10)=10 volt

Q. A sinusoidal carrier voltage is amplitude modulated. The resultant amplitude modulated wave has maximum and minimum amplitude of $120 V$ and $80 V$ respectively. The amplitude of each sideband is :

$10 V$

$5 V$

$20 V$

$15 V$

$A_{c} + A_{m} = 120$
$A_{c} - A_{m} = 80$
$∴ \overline{A_{c}} = 100$
$A_{m} = 20$
Modulation index $= \frac{20}{100} = \frac{1}{5}$
Amplitude of each sideband
$= A_{c} \frac{( mod ulation index )}{2}$
$= 100 \times \frac{1}{10} = 10 v o lt$

Q. A sinusoidal carrier voltage is amplitude modulated. The resultant amplitude modulated wave has maximum and minimum amplitude of 120V and 80V respectively. The amplitude of each sideband is :

10V

5V

20V

15V