How to separate real and imaginary part of a complex FFT?

1. What is the real and imaginary part of FFT?
2. What is the imaginary part of a Fourier transform mean?
3. What are the two types of FFT?
4. What is the FFT of a complex number?

What is the real and imaginary part of FFT?

The real portion of an FFT result is how much each frequency component resembles a cosine wave, the imaginary component, how much each component resembles a sine wave.

What is the imaginary part of a Fourier transform mean?

If you consider the input as current, the transfer function or Fourier transform as impedance then the output is potential. If Fourier transform is impedance, then the real part of FT is resistive part of the impedance and imaginary part is the reactive part of the impedance.

What are the two types of FFT?

These are called the radix-2 and mixed-radix cases, respectively (and other variants such as the split-radix FFT have their own names as well).

What is the FFT of a complex number?

The FFT provides you with amplitude and phase. The amplitude is encoded as the magnitude of the complex number (sqrt(x^2+y^2)) while the phase is encoded as the angle (atan2(y,x)). To have a strictly real result from the FFT, the incoming signal must have even symmetry (i.e. x[n]=conj(x[N-n])).