Fft magnitude units

1. What is the unit of FFT magnitude?
2. Does FFT have units?
3. How is FFT magnitude calculated?
4. What does magnitude of FFT tell you?

What is the unit of FFT magnitude?

It is expressed in units of dBm/Hz. The frequency spectrum produced by the FFT is discrete; it has valid amplitude data only at k uniformly spaced frequency values.

Does FFT have units?

The FFT calculates sum of its input sampled at discrete time points multiplied by dimensionless values; the units of the result of the FFT are those of its input; there is no scaling by time or frequency in the process.

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);

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.