Communication Systems - Engineering

Q1:

For a FM wave carrier modulating frequency is 10 kHz and bandwidth is 2 MHz. If the modulating signal amplitude is doubled, the bandwidth will be

A 0.5 MHz

B 1 MHz

C 2 MHz

D 4 MHz

ANS:D - 4 MHz

D is correct because of frequency deviation= Kf * Vm.

So when Vm double then frequency deviation double so bandwidth is doubled.
Where Kf is a deviation sensitivity.