8/11/2019 lab_fm

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8/11/2019 lab_fm

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(c) FM demodulation based on the FM-AM conversion method: For this part you mayassume the message signal to be any time-limited signal. You may assume the (essential)bandwidth of the message signal to be 100 Hz. The carrier frequency can be taken to be400 Hz. The peak frequency deviation of the corresponding FM signal can be assumed tobe 100 Hz.

i. Plot the corresponding FM signal and its magnitude spectrum.

ii. Demodulate the FM signal by using a combination of bandpass differentiator and anenvelope detector. Plot the corresponding output signal after passing through the dif-ferentiator and envelope detector respectively. Compare the final demodulated outputsignal with that of the original message signal.

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