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For Amplitude Modulation, it is understood that the bandwidth of a

  1. Jul 21, 2011 #1
    For Amplitude Modulation, it is understood that the bandwidth of a passband signal is always twice as much as that of a baseband signal, for example
    if the bandwidth/max frequency of a message/baseband signal is 1 kHz and a carrier of 1 MHz is modulated with this baseband, then a "sum" frequency is produced at 1 MHz + 1 kHz, and a difference frequency is produced at 1 MHz - 1 kHz. Hence, the passband bandwidth is 2 KHz.
    Now, My question is what would have been the bandwidth of the baseband signal, if it were a Frequency Modulation (FM)? Consider the frequency remains same, i.e. Baseband signal is 1 KHz and Carrier signal is 1 MHz.

    Thanks in Advance.
     
  2. jcsd
  3. Jul 21, 2011 #2

    Averagesupernova

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    Re: bandwidth

    For FM the bandwidth is not quite as clear cut. If the modulation index is high, then the bandwidth will be what the frequency swing is, which is double of what the deviation is. Not familiar with these terms? Wiki should clue you in a bit.
     
  4. Jul 21, 2011 #3

    Averagesupernova

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    Re: bandwidth

    I also seem to recall explaining it on this forum a while ago. You may want to do a search.
     
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