Abstract Fountain codes provide an efficient way to transfer information over erasure channels like the Internet. LT codes are the first codes fully realizing the digital fountain concept. They are asymptotically optimal rateless erasure codes with highly efficient encoding and decoding algorithms. In theory, for each encoding symbol of LT codes, its degree is randomly chosen according to a predetermined degree distribution, and its neighbours used to generate that encoding symbol are chosen uniformly at random. Practical implementation of LT codes usually realizes the randomness through pseudo-randomness number generator like linear congruential method. This paper applies the pseudo-randomness of chaotic sequence in the implementation of LT codes. Two Kent chaotic maps are used to determine the degree and neighbour(s) of each encoding symbol. It is shown that the implemented LT codes based on chaos perform better than the LT codes implemented by the traditional pseudo-randomness number generator.
Received: 02 April 2008
Revised: 14 April 2008
Accepted manuscript online:
(Telecommunications: signal transmission and processing; communication satellites)
Fund: Project supported in
part by the National Natural Science Foundation of China (Grant Nos
60774088 and 10772135), the Program for New Century Excellent
Talents in University of China (NCET), and the Foundation of the
Application Base and Frontier Technology Research Project of Tianjin
(Grant Nos 08JCZDJC21900 and
07CYBJC05800).
Cite this article:
Zhou Qian(周茜), Li Liang(李亮), Chen Zeng-Qiang(陈增强), and Zhao Jia-Xiang(赵加祥) Implementation of LT codes based on chaos 2008 Chin. Phys. B 17 3609
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