Assignment:
A frequency downconverter is implemented using a square-law device as follows.
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The band-pass filter has a center frequency fi=|fc - ft| (also known as the intermediate frequency, IF). Assume that the message bandwidth of the input signal m(t) is equal to B Hz.
a) Determine the smallest possible IF frequency, so that there is no distortion in the output signal.
b) For a given IF frequency, what is the smallest bandwidth of the band-pass filter (BPF) so that there is no distortion in the output signal?
c) For a given IF frequency, what is the largest bandwidth of the BPF so that there is no distortion in the output signal?