logo

CuriousTab

CuriousTab

Discussion

Home ‣ Electronics and Communication Engineering ‣ Communication Systems Comments
  • 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).

    Communication Systems problems

    Search Results

    • 1. When the channel is noisy, producing a conditional probability of error p = 0.5; the channel capacity and entropy function would be, respectively,

    • Options
    • A. 1 and 1
    • B. 1 and 0.5
    • C. 0.5 and 1
    • D. 0 and 1
      • Discuss
    • 2. If the bandwidth is increased by 2, the ?FM ?AM (where ? is the ratio of SNR of output to SNR at input, FM is frequency modulation and AM is amplitude modulation) is increased by a factor of

    • Options
    • A. 2
    • B. 3
    • C. 4
    • D. 6
      • Discuss
    • 3. Space wave may be a direct wave or wave reflected from earth.

    • Options
    • A. True
    • B. False
      • Discuss
    • 4. Degaussing in a picture tube means

    • Options
    • A. Adding magnetism in mask and mounting frame
    • B. Removing residual magnetism in mask, shield etc...
    • C. Increasing resistance of coils to decrease time constant
    • D. Decreasing resistance of coils to increase time constant.
      • Discuss
    • 5. Which of the following has the highest input impedance?

    • Options
    • A. CE
    • B. CB
    • C. CC
    • D. Push pull
      • Discuss
    • 6. A carrier is simultaneously modulated by two sine waves having modulation indices of 0.4 and 0.3. The total modulation index will be

    • Options
    • A. 0.1
    • B. 0.7
    • C. 0.5
    • D. 0.35
      • Discuss
    • 7. In radar systems PRF stands for

    • Options
    • A. Power Return Factor
    • B. Pulse Return Factor
    • C. Pulse Repetition Frequency
    • D. Pulse Response Factor
      • Discuss
    • 8. In a fascimile reproduction time to scan one line is 2 ms. If it has 4% blanking, the visible trace time is

    • Options
    • A. 1.92 ms
    • B. 2.08 ms
    • C. 50 ms
    • D. 0.08 ms
      • Discuss
    • 9. The rate at which information can be carried through a communication channel depends on

    • Options
    • A. carrier frequency
    • B. bandwidth
    • C. transmission loss
    • D. transmitted power
      • Discuss
    • 10. A telephone exchange has 9000 subscribers. If the number of calls originating at peak time is 10, 000 in one hour, the calling rate is

    • Options
    • A. 0.9
    • B. 10/9
    • C. 0.81
    • D. 0.1
      • Discuss

    Comments

    There are no comments.
Enter a new Comment




Aptitude

Engineering

Programming

Reasoning

Links

Copyright ©CuriousTab. All rights reserved.