Using MATLAB, when you perform an FFT on a signal such as A sin( omega*t ), why is the amplitude of the FFT not A*n/2?
The magnitude of the FFT should be A*n/2, where "n" is the number of points used in the FFT.
I am using the following code to find the power spectrum:
t = 0:0.001:0.6;x = sin(2*pi*50*t);Y = fft(x,512);f = 1000*(0:256)/601;plot(f,abs(Y(1:257)))
In this absolute FFT plot, the peak occurs at the frequency 50, but the amplitude of the peak is NOT
1*512/2 (A*n/2)
as suggested by the formula, but much less.
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