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Unformatted text preview: Use max(abs(mn)) to verify that the maximum absolute value of mn is 1. We want to create an AM signal with carrier frequency fc = 12 kHz. Say that we set the AM modulation index to a = 0.85. We can use the commands a=0.85; N=length(xi); n=[0:1:N 1]; fi=88200; Ti=1/fi; xAM=(1+a*mn’).*cos(2*pi*12000*Ti*n); %Note: need to convert mn to a row vector using mn’ Plot xAM vs. time – comparing this to the plot of xi from part (b), you should see that xi forms the upper envelope of xAM. Also plot the positive frequency part of the magnitude of the DFT of xAM vs. CT frequency f. You should see that the message Fourier Transform (as found in part (b)) has been shifted to a center frequency of 12 kHz. You should also see a...
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This homework help was uploaded on 03/06/2014 for the course ECE 563 taught by Professor Goeckel during the Fall '11 term at UMass (Amherst).
 Fall '11
 Goeckel
 Signal Processing

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