The FFT Excel program is updated to v2.0. You can download it on the bottom of this page or the new page. The new version performs FFT for 64 kBytes data in 1 second. (235ms for 16 kBytes data) FFT(Fast Fourier Transformation) can be done in the Excel's internal function. However it has limitation of data size 4096 and it works a little slow. Therefore, I decided to make FFT code with Excel VBA...
