In real time processing we obviously can't use DFT because it is slow in processing due to lots of calculations. So we use FFT which is Fast Fourier Transform. An FFT is a way to compute same result more quickly : computing the DFT of N points in naïve way, if we go by the definition of DFT it will take N*N arithmetic operations while FFT can compute the same DFT in only NlogN operations. We implemented this using Cooley and Tukey's radix-2 DITFFT algorithm. DITFFT stands for Decimation In Time Fast Fourier Transform. Signal is decimated in time domain so as to reduce no. of calculations, reducing calculations means increase in speed.
Decomposition reduces calculation.
ReplyDeleteYes that is why it widely used.
DeleteFFT is faster than DFT
ReplyDeleteCorrect
DeleteFFT reduces the calculations hence increases the speed
ReplyDeleteYes that true
DeleteHow is it faster?
ReplyDeleteBecause in this method we decompose the input signal and decomposition reduces calculation
Delete