8 Effects of over modulation?

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 Modulation index :-

It is defined as the ration of maximum amplitude of message signal to maximum amplitude of carrier signal .


                M= Vm / Vc

        M = modulation index

        Vm = maximum amplitude of message signal

      Vc = maximum amplitude of carrier signal


Effects of over modulation?

if M>1 it is called as over modulation ,due to this some problems will occurs in transmission .

  • transmission quality will be poor
  • envelop will occur in receiver(negative peak clipped off)
  • excessive bandwidth required
  • instability in carrier voltage,frequency
  • interference with neighboring station signal may occur

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