Question:
Given below are two statement :
Statement-I: A speech signal of $2 \mathrm{kHz}$ is used to modulate a carrier signal of $1 \mathrm{MHz}$. The band width requirement for the signal is $4 \mathrm{kHz}$.
Statement-II : The side band frequencies are $1002 \mathrm{kHz}$. and $998 \mathrm{kHz}$.
In the light of the above statements, choose the correct answer from the options given below:
Correct Option: , 3
Solution:
$f_{m}=2 k H z$
$f_{c}=1 M H z=1000 \mathrm{kHz}$
Band width $=2 \mathrm{f}_{\mathrm{m}}=4 \mathrm{kHz}$
$\therefore$ Side frequencies will be
$=\mathrm{f}_{\mathrm{c}} \pm \mathrm{f}_{\mathrm{m}}$
$=(1000 \pm 2) \mathrm{kHz}$
$=998 \mathrm{kHz} \& 1002 \mathrm{kHz}$
So statement-I \& statement-II both are correct.