Explain the concept of De-emphasis with neat diagram.

Explain the concept of De-emphasis with neat diagram. 
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In the De-emphasis circuit, by reducing the amplitude level of the received high frequency signal by the same amount as the increase in pre-emphasis is termed as De-emphasis. The pre-emphasis process is done at the transmitter side, while the de-emphasis process is done at the receiver side. Thus a high frequency modulating signal is emphasized or boosted in amplitude in transmitter before modulation. To compensate for this boost, the high frequencies are attenuated or de-emphasized in the receiver after the demodulation has been performed. Due to pre-emphasis and de-emphasis, the S/N ratio at the output of receiver is maintained constant. The de-emphasis process ensures that the high frequencies are returned to their original relative level before amplification. Pre-emphasis circuit is a high pass filter or differentiator which allows high frequencies to pass, whereas de-emphasis circuit is a low pass filter or integrator which allows only low frequencies to pass. 

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