claudiocamera
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Hi there!
Sorry for the simple question, I just can't figure out what is going on ... We know that the FT of a cosine is given by:
x(t) = cos(ωot) ----FT---- X(jω) =πδ( ω-ωo) + πδ( ω+ωo).
In this way, I would expect that in the plot given by the code below the amplitude value were 10π instead of 5 as it is showing. Someone can explain-me why this happen?
Fs =1000; % Sample Frequency
T=5;
t= 0:1/Fs:T ; % vector of time
s= 10*cos(2*pi*60*t); % signal itself
% FFT performing block
F=fft(s);
F1=fftshift(F);
F2= abs(F1)/(length(F1)-1);
w=(-2.5:1/Fs:2.5)*Fs/T;
plot(w,F2)
Sorry for the simple question, I just can't figure out what is going on ... We know that the FT of a cosine is given by:
x(t) = cos(ωot) ----FT---- X(jω) =πδ( ω-ωo) + πδ( ω+ωo).
In this way, I would expect that in the plot given by the code below the amplitude value were 10π instead of 5 as it is showing. Someone can explain-me why this happen?
Fs =1000; % Sample Frequency
T=5;
t= 0:1/Fs:T ; % vector of time
s= 10*cos(2*pi*60*t); % signal itself
% FFT performing block
F=fft(s);
F1=fftshift(F);
F2= abs(F1)/(length(F1)-1);
w=(-2.5:1/Fs:2.5)*Fs/T;
plot(w,F2)