Given message signal m(t) = sin (2000 πt), Kf = 100 kHz/V

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Given message signal
m(t) = sin (2000 πt), K_f = 100 kHz/V and K_p = 10 rad/V. The bandwidth of FM and PM signals are respectively—

1. 204 kHz, 44 kHz
2. 202 kHz, 22 kHz
3. 402 kHz, 42 kHz
4. None of these

Correct Option: B

Given m(t) = sin (2000πt)
K_f = 100 kHz/V
K_p = 10 rad/V.
for FM: BW = 2 (Δf + f_m)
Δf = |K_f A_m|_max = 1000 × 1 = 100 kHz
f_m = 1000 Hz or 1 kHz
Now BW = 2(100 + 1) = 202 kHz
for PM:

Δf =	\|Kp d/dt m(t)\|	Hz
	2π

Δf =	10	× 2000π = 10kHz
	2π

BW = 2(Δf + f_m) = 2 (10 + 1) = 22 kHz
Hence alternative (B) is the correct choice.