Doped LT Decoding with Application to Wireless Broadcast Service

In this paper, we consider the doped decoder for Luby-Transform (LT) codes, where based on the decoder feedback, the decoding process is revived by retransmission of the in formation packet. We propose several improved doping methods to reduce the average doping rate. We then provide an analysis of the proposed doping methods based on the study of the decoding ripple evolution. Both analytical and simulation results show that the proposed doping approaches provide significant performance gain over the existing random doping strategy. We then apply the doped LT decoding to the wireless broadcast system in which limited feedback is allowed. We propose a majority vote based doping selection and demonstrate the efficiency of the proposed doping selection through simulations.