Application of Chaos in Digital Fountain Codes

Fountain codes provide an efficient and reliable way to transfer information over erasure channels like Internet. LT codes are the first practical realization of Fountain codes. Implementation of fountain codes usually realizes the randomness in the encoding through pseudo-random number generator. We apply chaotic sequence in the implementation of LT codes to determine the degree and neighbour(s) of each encoding symbol. It is shown that the implemented LT codes based on chaos can perform better than the LT codes implemented by the traditional pseudo-randomness number generator. Receiver and sender can communicate neighbor information by sending the initial conditions of Kent maps, which greatly reduces the transmission consumption. LT codes with our revised Robust Soliton distribution are shown to have comparable decoding efficiency with the Robust Soliton distribution. Moreover, they reduce the symbol operations numbers in the decoding, which can make the decoding more efficient.