Question

why zero padding is used in linear convolution

Answer 1

Zero-padding for cross correlation is used to not mix convolution results (due to circular convolution). The full result of a linear convolution is longer than either of the two input vectors.

Answer 2

Concept:

Linear convolution is a mathematical procedure that determines the output of any Linear-Time Invariant (LTI) system based on its input and impulse response.

Given:

Zero padding in linear convolution.

Find:

The reason for the usage of zero padding in linear convolution.

Solution:

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. In order to employ an extremely efficient FFT implementation.