Hi friends,
Sorry for a strange question, but can anyone tell me where FFT is used?
I think it would be useful for all the beginners in digital signal processing.
Please everybody, give, maybe, some links or say (in two words) where you implemented your fft.
Any information will be useful.
I hope you know that FFT is 'only' a calculation method for the Discrete Fourier Transform. So where ever you have application of DFT, you can use FFT.
Some examples include Frequency Domain analysis, to make OFDM etc
What is the FFT? FFT = Fast Fourier Transform. The FFT is a faster version of the Discrete Fourier Transform (DFT). The FFT utilizes some clever algorithms to do the same thing as the DTF, but in much less time.
Ok, but what is the DFT? The DFT is extremely important in the area of frequency (spectrum) analysis because it takes a discrete signal in the time domain and transforms that signal into its discrete frequency domain representation. Without a discrete-time to discrete-frequency transform we would not be able to compute the Fourier transform with a microprocessor or DSP based system. It is the speed and discrete nature of the FFT that allows us to analyze a signal's spectrum with
Matlab or in real-time.
Added after 9 minutes:
also you can google it to find many resources for it
Frequency analysis means analysis of a TIME domain signal in the FREQUENCY domain. This is done because (generally) frequency domain characteristics give more precise results than their time domain counterparts.
Also, freq-domain characters tend to be more or less immune to noise (1 or 2 hz difference is virtually insignificant compared to a 10-20 mV change in the time domain).
In case you want to learn more about signal processing in the frequency domain, read Digital Signal Processing by Oppenheim & Schaffer.