Audio sine waves of 3 kHz frequency are used to amplitude modulate a carrier signal of 1.5 MHz. Which of the following statements are true?

Options

A. The size band frequencies are `1506 kHz and 1494 kHz`
B. The bandwidth required for amplitude modulation is `6 kHz`
C. The bandwidth required for amplitude modulation is `3 kHz`
D. The size band frequencies are `1503 kHz and 1497 kHz`

Answer

B, D

Explanation

`omega_(m) = 3 kHz , omega _( c) = 1.5 MHz = 1500 kHz`
Side band frequencies ` = ( omega _(c) - omega _(m)) and ( omega_(c ) + omega _(m)) = ( 1500 - 3 ) kHz and ( 1500 + 3 ) kHz`
`= 1498 kHz and 1503 kHz`
Band width ` = 2 omega _(m) = 2 xx 3 = 6 kHz`