DISCRETE FOURIER TRANSFORM
Discrete fourier transform(DFT) gives periodic results.It is frequency sampled version of discrete time fourier transform.DFT is a slow algorithm.
In this experiment,initially a 4 point sequence was taken and it's DFT was found out using C program.Then this same sequence was appended by 4 zeros to form a 8 point sequence.It's DFT output was found out.Then magnitude spectrum was plotted for both output sequence.It was observed that the magnitude spectrum of 8 point input sequence was more accurate than 4 point input sequence.It was because the resolution of magnitude spectrum of 8 point sequence was higher.
This method takes more computing than Fast Fourier Transform
ReplyDeleteDFT is obtained by sampling of DTFS
ReplyDeleteFFT is more faster than DFT
ReplyDeleteDFT requires more computations
ReplyDeleteDFT is computationally less efficient than FFT as DFT requires more number of multiplications and additions
ReplyDeleteDFT is a discrete version of DTFT which is continuous
ReplyDeleteDFT assumes input signal to be periodic and hence gives discrete spectrum
ReplyDelete