Power spectrum phase correction method in Fourier Transform

miguelG's picture

Hello everyone,

Has anyone heard of "power spectrum method". All that I have is that it is a phase correction in Fourier transform of interferograms. I cannot seem to figure out this procedure and a tough literature search has not helped. Any help would be appreciated.

Richard Jackson's picture

After the Fourier transform you have real and imaginary spectra. To get the final spectrum you have to use those to calculate the spectrum with the correct phase rotation. One way to do that is to calculate the square root of the real squared plus the imaginary squared (ie. SQRT(Re2+Im2) ). This is the magnitude spectrum, and this phase correction method is referred to as either magnitude or power (even though the latter is not really correct, because the power spectrum is the sum of the squares, with no square root).

miguelG's picture

Thank you very much @Richar Jackson! 

I was stuck because I could not find any text that would give me the procedure to the phase correction of the "power spectrum" method. Using the magnitude now is working perfectly!