harrison@sunwhere.DAB.GE.COM (Gregory Harrison) (08/24/90)
Hi: are you familiar with FLAT TOP WINDOWS? Applied to an FFT, I believe that they greatly reduce the scalloping loss. The way I understand it is that when a frequency component is reflected in the FFT generated spectrum, unless the frequency is directly aligned with the frequency corresponding to an FFT bin, there will be a loss associated with that frequency's reflected power. At a Spectral Dynamics seminar, someone mentioned that poeple are using the flat top window more and more, because it minimizes the power loss for signals that aren't directly on top of a bin. This seems to correspond with a minimum scallop loss as presented in Frederic J. Harris' fine paper "On the Use of Windows for Harmonic Analysis with the Discrete Fourier Transform", Proc. IEEE, V66 No. 1 Jan 1978. Supposedly, Harris also came up with the flat top window, but I'm not sure. Do you have any more information that you could please relay? Thank You, Greg Harrison GE Daytona