MATLAB: How do we apply Discrete Time Fourier Transform (DTFT) to the signal? what is the difference between DFT, DTFT and FFT

Question

I am now doing my research on vibration analysis. throughout my research, Ive found that Dirichlet fourier transform is refering to DTFT. but still I do not understand on how to apply DTFT to the signal? is it same function like DFT and FFT?

please help me. I am new in Matlab and signal processing.

Answer 1

I’m not certain how you’re applying the Dirichlet kernels (I’ve never used them), but the MATLAB fft function should do what you want. I always considered ‘DTFT’ to be the ‘discrete time Fourier transform’, the Fourier transform applied to discretely-sampled signals of the sort that you will be dealing with in your research.