关键词: 喷泉码, 硬译码, 延时, 抖动

Abstract:

Due to high flexibility to different channels, fountain codes with hard-decoding algorithm are used in many applications such as the board-band Internet. However, hard-decoding suffers from the delay and jitter caused by the randomness of encoding. The delay and jitter were minimized with analysis and computational optimization. Firstly, expressions of delay and jitter determined by degree distribution were deduced under any erasure probability. Secondly, several short-length fountain codes with small delay and jitter were developed from previous work through simulation and optimization. As a significant improvement, two raptor codes with length at 1 024 will offer minimized delay and jitter as 9.56% and 3.22%.

Key words: fountain codes, hard-decoding, delay, jitter