JEE Main · 2022 · 28 Jul 2022 · Shift 2 · Semiconductors

A FM Broad cast transmitter, using modulating signal of frequency 20 kHz has a deviation ratio of 10. The Bandwidth required for transmission is :

Answer: (D)

Solution

The deviation ratio is defined as

\frac{Δ f}{f}

, where

Δ f

is the frequency deviation and

f

is the modulating frequency.

Given deviation ratio = 10 and

f = 20

kHz:

Δ f = 10 \times 20 = 200

kHz.

Bandwidth for FM is given by Carson's rule:

B W = 2 (f + Δ f) = 2 (20 + 200) = 440

kHz.

JEE Main · 2022 · 28 Jul 2022 · Shift 2 · Single correct option