Pre emphasis in FM
Q. Pre emphasis is done before- Published on 14 Oct 15a. Before modulation
b. Before transmission
c. Before detection at receiver
d. After detection at receiver
ANSWER: Before modulation
Pre-emphasis is done for boosting the relative amplitudes of the modulating voltages at higher audio frequencies. In this method, the artificial emphasis of high frequency components of message signal is done before modulation in the transmitter. As higher frequency signals are more prone to noise, the boosting of signals is done to avoid noise.