Unequal Error Protection Source–Channel Coding
Andres Kwasinski, Vinay Chande · 2022
While an error in one part of the bit stream may add little distortion to the source reconstruction, an error of the same magnitude may have a devastating effect on a different part. This is a case where following Shannon's source–channel coding theorem would result in a performance penalty. A sensible approach is to apply error protection of different strength to the different parts of the bitstream, based on each part's impact on distortion. This approach exemplifies a class of joint source–channel coding techniques known as unequal error protection (UEP) source–channel coding. A number of techniques that apply UEP can be seen as derived from the concept of priority encoding transmission . Digital fountain codes, also known as rateless codes , allow for low complexity encoding and decoding and require almost no feedback.