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  • Question

  • c(t) and m(t) are used to generate an FM signal. If the peak frequency deviation of the generated FM signal is three times the transmission bandwidth of the AM signal, then the coefficient of the term cos [2p(1008 x 103t)] in the FM signal (in terms of the Bessel Coefficients) is


  • Options
  • A. 5 J4(3)
  • B. c(t) and m(t) are used to generate an FM signal. If the peak frequency deviation of the generated FM J8(3)
  • C. c(t) and m(t) are used to generate an FM signal. If the peak frequency deviation of the generated FM J8(4)
  • D. 5 J4(6)

  • Correct Answer
  • 5 J4(6) 

    Explanation
    As, we known FM, s(t)

    c(t) and m(t) are used to generate an FM signal. If the peak frequency deviation of the generated FM

    ⟹ Frequency deviation = 3 . (AM Bandwidth) = 6 fm

    c(t) and m(t) are used to generate an FM signal. If the peak frequency deviation of the generated FM

    and ?= 6 is given in (d) only.

    ?c + n ?m = (1008 x 103)2p

    ⟹ 2p x 106 + n. 4p x 103 = (1008 x 103).2p

    ⟹ n = 4

    So, ? = 6, n = 4 hence answer is 5j4(6).

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