FFT of signal with starting value zeros

1. Does zero padding affect FFT?
2. Why zero padding is needed in FFT?
3. Does zero padding improve FFT resolution?
4. How many points do you need for FFT?

Does zero padding affect FFT?

Zero padding allows one to use a longer FFT, which will produce a longer FFT result vector. A longer FFT result has more frequency bins that are more closely spaced in frequency.

Why zero padding is needed in FFT?

In addition to making the total number of samples a power of two so that faster computation is made possible by using the fast Fourier transform (FFT), zero padding can lead to an interpolated FFT result, which can produce a higher display resolution.

Does zero padding improve FFT resolution?

Zero padding enables you to obtain more accurate amplitude estimates of resolvable signal components. On the other hand, zero padding does not improve the spectral (frequency) resolution of the DFT. The resolution is determined by the number of samples and the sample rate.

How many points do you need for FFT?

Because the FFT function uses a base 2 logarithm by definition, it requires that the range or length of the time series to be evaluated contains a total number of data points precisely equal to a 2-to-the-nth-power number (e.g., 512, 1024, 2048, etc.).