PHYSICAL LAYER AND TRANSMISSION MEDIA
ANALOG TRANSMISSION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Reducing signal amplitude by equal proportions after demodulator in FM receiver
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Reducing frequency in fm
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Incerasing SNR
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Decreasing SNR
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Detailed explanation-1: -Pre-emphasis works by boosting the high-frequency portion of the signal. This compensates for the high-frequency loss in the cable. De-emphasis works by cutting the low-frequency portion of the signal. This may be coupled with an increased transmit voltage.
Detailed explanation-2: -Preemphasis increases the magnitude of the higher signal frequencies, thereby improving the signal-to-noise ratio. At the output of the discriminator in the FM receiver, a deemphasis network restores the original signal power distribution.
Detailed explanation-3: -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.