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Confused with Technical Note 1702 !!!
Posted:
Aug 8, 1996 8:56 PM


Hi everyone,
Some time ago, someone posted a news regarding the Mathworks technical note 1702. I read the technical note and got pretty confused. Could someone (may some Mathworks guy) answer the following questions :
(1) I can still understand why we want to throw out the second half of the FFT. But I don't understand why we need to multiply the FFT by 2.
(2) The technical note mentions that MATLAB doesn't scale the output of fft by the length of the input. According to the book "DiscreteTime Signal Processing" by Oppenheim and Schafer, pp. 532, 1989, there is no scaling factor in finding the Discrete Fourier Transform (which is the same as fft in MATLAB). So why do we need to scale the output of fft ? Is it because we are using slightly different definitions of Discrete Fourier Transform ?
Thanks for your time reading my news and hopefully you will answer my questions !!!
Kevin Hung



