How Exactly Does MATLAB Zero Pad Signal?

1. How does zero padding work?
2. How does zero padding increase frequency resolution?
3. How does zero padding affect FFT?

How does zero padding work?

In zero padding, you add zeros to the end of the input sequence so that the total number of samples is equal to the next higher power of two. For example, if you have 10 samples of a signal, you can add six zeros to make the total number of samples equal to 16, or 32, which is a power of two.

How does zero padding increase frequency 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 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.