Temporal waveform reconstruction from spectral magnitude only

I have spectral data that represents magnitude in frequency space. I'd like to convert this data into the time domain to produce a temporal waveform, but I have no phase data. Has anybody approached this problem in MATLAB, and if so how? I've read a bit about the cepstrum analysis in the Signal Processing toolbox (which I have) but it's not clear to me how that might help.

Answer 1

[Daniel kiracofe]

Without the phase data, it's basically impossible to reconstruct the original time domain signal. Sorry. Cepstrum analysis will not help you. Cepstrum is taking an FFT of an FFT. What you are thinking about is taking the inverse FFT, which is not the same as a cepstrum. But since you don't have the phase data, you can't do inverse FFT.