Howtosignalprocessing
- What does DFT do to a signal?
- What are the limitations of discrete Fourier transform?
- Can a signal be causal?
What does DFT do to a signal?
The Discrete Fourier Transform (DFT) is of paramount importance in all areas of digital signal processing. It is used to derive a frequency-domain (spectral) representation of the signal.
What are the limitations of discrete Fourier transform?
These signals can be represented as the sum of a random discrete signal and harmonics of various frequencies. In the Fourier analysis of mixed-structure signals, the disadvantages of DFT are most significantly manifested. These disadvantages are picket-fence, leakage, aliasing effects and amplitude modulation spectrum.
Can a signal be causal?
A continuous time signal 𝑥(𝑡) is called causal signal if the signal 𝑥(𝑡) = 0 for 𝑡 < 0. Therefore, a causal signal does not exist for negative time. The unit step signal u(t) is an example of causal signal as shown in Figure-1.
