An enhanced coding and decoding method for raptor codes over fading channels

Abstract

In this paper, an improved decoding algorithm is developed for Raptor codes in fading channels to enhance its error performance. As the classic decoding algorithm of the Raptor codes is designed for erasure channels and its error performance degrades severely over the fading channels, a modified coding and decoding algorithm is developed for Raptor codes with short codeword length in fading channels. A random interleaver is introduced between the inner LT code and the outer LDPC code, and then an iterative soft information upgrading and transferring-based decoding algorithm under Turbo principle is employed to combat the fading. Simulation results show the presented coding and decoding algorithm can enhance the bit error rate(BER) performance of Raptor codes in fading channels.