DSPRelated.com
Forums

Re: AW: Real Symmetric FFT

Started by Jeff Brower December 9, 2003
Andor-

> > > the source code for the Real FFT can be downloaded from ADI. It
> > > implements a real N-point FFT using a N/2-point complex FFT, plus
> > > some signal reassembling.
> > >
> > > If the input signal is however real _and_ symmetric (as is the case
> > > for a linear-phase frequency response), additional speed-up can be
> > > achieved as compared to the Real FFT, because the resulting
> > imaginary
> > > part does not have to be calculated.
> >
> > Just curious, but how can a real signal in time domain be
> > symmetric?
>
> Hi Jeff,
>
> the signal is not in time domain. The application is frequency sampling
> FIR design (I mentioned this in the original post).

That application does not do "FFT of an FFT", so your explanation is still not
clear.

-Jeff