An Advanced Relaying Scheme for Distributed LT Code Systems

This paper describes a new relaying scheme to reduce overhead of LT coded networks. The most popular degree distribution of LT codes is robust soliton distribution (RSD) which has low decoding complexity and decoding failure probability. This paper proposes a relaying scheme that makes degree distribution of encoding symbol at the sink equal to RSD, under the assumption that the each source generates encoding symbols according to RSD. The proposed relaying scheme and the assumption are appropriate for the network model organized by two sources, one relay and multiple sinks which receive data from one source or two sources. In this paper, four operations of relay are defined and class is introduced to determine which operation is used to generate output symbols. Moreover class distribution is defined and derived to make the statistical degree distribution at sink equal to RSD. From the simulation results, it can be confirmed for ARS to reduce the overall data traffic of the network model.