Fast Fourier Transforms How engineers do it Watch the video

Fast Fourier Transforms. How engineers do it! Watch the video at: https://www. youtubecom/watch?v=dM1 y6ZfQkPU Execute the code for the example in the video in MatLab and printout the time domain, magnitude spectra, and phase spectra for the FFT. Also, use Matlab to find the phase of the 3 frequency components and include those values in your answer.

Solution

fs=1000;
t=0:1/fs:1.5-1/fs;
f1=20;
f2=30;
f3=40;
x=3*cos(2*pi*f1*t*+0.2)+1*cos(2*pi*f2*t-0.3)+2*cos(2*pi*f3*t+2.4);
X=fft(x);
Xmag=abs(X);
Xphase=angle(X);
plot(Xmag);
Xphase(31)
Xphase(46)
Xphase(61)