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JEE Main20199 Apr 2019Morning ShiftPhysicsCommunication SystemActual

A signal A c o s ω t is transmitted using ν 0 s i n ω 0 t as carrier wave. The correct amplitude modulated ( A M ) signal is:

Options

  1. Aν 0 s i n ⁡ [ ω 0 1 + 0.01 A s i n ω t t ]
  2. Bν 0 + A c o s ω t s i n ω 0 t
  3. Cν 0 s i n ω 0 t + A c o s ω t
  4. Dν 0 s i n ω 0 t + A 2 sin ⁡ ω 0 - ω t + A 2 sin ⁡ ω 0 + ω t

Correct answer

D. ν 0 s i n ω 0 t + A 2 sin ⁡ ω 0 - ω t + A 2 sin ⁡ ω 0 + ω t

Step-by-step solution

y m = A c o s ω t y c = V 0 s i n ω 0 t Modulated signal = V 0 + A c o s ω t s i n ω 0 t = V 0 s i n ω 0 t + A c o s ω t s i n ω 0 t = V 0 s i n ω 0 t + A 2 s i n ω 0 - ω t + A 2 s i n ω 0 + ω t

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