Howtosignalprocessing
- What is the magnitude in FFT?
- What does magnitude of FFT tell you?
- How is FFT magnitude calculated?
- How do you normalize FFT magnitude?
What is the magnitude in FFT?
Basically, the magnitude of the FFT is the amplitude of the associated frequency component. When you're using the FFT function in MATLAB you probably also want to use the fftshift function to center the results around 0. Hope that helps.
What does magnitude of FFT tell you?
The output of the FFT is a complex vector containing information about the frequency content of the signal. The magnitude tells you the strength of the frequency components relative to other components. The phase tells you how all the frequency components align in time.
How is FFT magnitude calculated?
1) Division by N: amplitude = abs(fft (signal)/N), where "N" is the signal length; 2) Multiplication by 2: amplitude = 2*abs(fft(signal)/N; 3) Division by N/2: amplitude: abs(fft (signal)./N/2);
How do you normalize FFT magnitude?
Normalise the fft by dividing it by the length of the original signal in the time domain. Zero values within the signal are considered to be part of the signal, so 'non-zero samples' is inappropriate. The length to use to normalise the signal is the length before adding zero-padding.
