What is meant by pre-emphasis and
de-emphasis?

• pre-emphasis means boosting the received signal before given it into amplifier of for working.by donig this noise signal & msg signal both boost to a high frequency and now we do de-emphasis by this we remove that contains high frequency so noise signal of high frequency is removed.so that is why we do pre-emphasis and
  de-emphasis.
• 10 years agoHelpfull: Yes(10) No(1)
• high frequency message signals are affected by the noise the most.So we amplify the high frequency components at the transmitted and then do the reverse of it at receiver(attenuate at receiver)
  
  Note:In case of fm transmitter noise is directly proportional to the square of
  frequency.
• 10 years agoHelpfull: Yes(3) No(0)