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Shannon's Formula c = b log2 (1 + s)

  1. Apr 17, 2003 #1
    im trying to understand shannon's formula for some time now. i have tryed to theorise if this is correct the way i have worked out an example using the formula below.

    c = b x log2 (1 + s)

    for example

    signal to noise ratio 127
    b = 3000 b = bandwidth
    as shannon's formula states to add one to the signal to noise ratio to make it 128

    Log 2 = 27= 128

    then we multiply the log2 by the bandwidth to get

    21000 Bps


    in formula the answer

    21000 = 3000 x log2

    is that correct?
    Last edited by a moderator: Apr 17, 2003
  2. jcsd
  3. Apr 21, 2003 #2


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    You get the right answer, but your presentation is confusing. You should state clearly that the log of 128 to the base 2 is 7, and then show the multiplication of that 7 by 3000 to give the answer 21000.

    The way you have it now gives a first impression of being wrong.
  4. Apr 26, 2003 #3
    128 = log to the base 2 is 27

    7 x 3000 = 21000bps
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