Howtosignalprocessing
- What does zero padding do?
- What does zero padding do to FFT?
- Why zero padding is used in linear convolution?
- Is zero padding is mandatory for both linear and circular convolution?
What does zero padding do?
Zero padding is a technique typically employed to make the size of the input sequence equal to a power of two. 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.
What does zero padding do to 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 used in linear convolution?
Zero padding enables the use of a longer FFT, resulting in a larger FFT result vector. The frequency bins of a lengthier FFT result are more closely spaced in frequency. It can quickly compute linear convolutions using the FFT. It's used to make the FFT bigger for a power of two.
Is zero padding is mandatory for both linear and circular convolution?
The linear convolution of an N-point vector, x , and an L-point vector, y , has length N + L - 1. For the circular convolution of x and y to be equivalent, you must pad the vectors with zeros to length at least N + L - 1 before you take the DFT.
