11 Define pre-emphasis and de-emphasis ?

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 PRE-EMPHASIS:

Artificially increasing the strength of amplitude & frequency components of a message signal before modulation process is called pre-emphasis .

or

Strengthening the message signal before modulation process is called pre-emphasis

 DE-EMPHASIS:

Artificially reducing the strength of amplitude & frequency components of a message signal after de-modulation process is called de-emphasis .

or

reducing  the strength message signal after de-modulation process is called de-emphasis


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