When I plot the frequency domain the power is not 3 and 5 as I expect. I read the documentation for fft() and cannot figure out how to normalize my fft properly. Can someone explain the procedure to normalize the cosines and a Gaussian wave? Thanks
clear all;%generate the signal
t = 0:1/2000:.02;x = 3*cos(2*pi*60*t) + 5*cos(2*pi*200*t);%sample the signal
fs = 1000;t1000 = 0:1/fs:.02; % number of sample points
n1000 = 0:length(t1000)-1; % number of intervals
x1000 = 3*cos(2*pi*60*n1000/1000) + 5*cos(2*pi*200*n1000/1000) ; %cos(2*pi*60*n*ts);
%Compute FT
z = fftshift(fft(x1000));f = -fs/2: fs/(length(n1000)-1): fs/2 ;%plot time domain
figuresubplot(2,1,1)plot(t,x)hold on;grid on;stem(t1000, x1000, 'filled', 'r', 'LineWidth', 2);%plot freq domain
subplot(2,1,2);plot(f,abs(z)); %normalization??
grid on;xticks(-500:50:500);xlim([-300 300]);
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