Dft.txt

as the sampling frequency becomes high the distance betweenconcequtive descrite samples became small and easy to recover the original signal. if you sample below the fundamental frequency it is unable to recover the signal may be you recover somthing different which may be its integer multiple of the frequency. Nyquist theorm tells us the minimum allowable sampling frequency inorder to be sure to recover the signal which is FS =2FM where Fm is the the maximum signal frequency means for one complete cycle (f=1/T) we need to take 2 smples. nyquist rate refers to sampling rate required for a frequency to not alias nyquist frequency is the maximum freq that will not alias given a smpling rate Dft used for spectral analysis (example finding periodicity) denoising compression filtering fast convolution