How to rebuild a signal after a FFT?
Rebuilding original signal from frequencies, amplitude, and phase obtained after doing an fft. I’m trying to rebuild a signal from the frequency, amplitude, and phase obtained after I do an fft of a signal, but when I try and combine the fft data (frequency, amplitude, and phase) back to see if I get a similar signal, the pattern is a little off.
How is each point in a FFT a complex number?
So each point in an FFT is a complex number that contains information about the phase and amplitude at that frequency. You’re extracting this information with these lines: You’re getting the magnitude and phase of each complex number, converting from rectangular complex number to polar form.
How is the amplitude spectrum obtained from fftshift?
The amplitude spectrum is obtained For obtaining a double-sided plot, the ordered frequency axis (result of fftshift) is computed based on the sampling frequency and the amplitude spectrum is plotted. 3b. Extract phase of frequency components (phase spectrum) Extracting the correct phase spectrum is a tricky business.
How to obtain a double-sided plot using FFT?
For obtaining a double-sided plot, the ordered frequency axis (result of fftshift) is computed based on the sampling frequency and the amplitude spectrum is plotted. 3b. Extract phase of frequency components (phase spectrum) Extracting the correct phase spectrum is a tricky business. I will show you why it is so.
How to get the original signal from two Mags?
You’d do this for each mag, phase pair in the two vectors, combining them back into a single vector of the original length, made up of complex numbers. Then feed this to the IFFT. If you hadn’t made any changes, it should return the original signal.
Do you have to re-implement Ifft when you don’t have to?
This is what the IFFT is for. Do your modifications to the spectrum, and then get them back into the form IFFT expects, and then do an IFFT. Don’t bother trying to re-implement the IFFT when you don’t have to. It will be slower and more error-prone.