Multiple Configurations LT Codes

This paper introduces a new scheme of LT codes, named multiple configurations. In multiple configurations LT codes (MC-LT codes), multiple sets of output symbols are simultaneously provided to receivers for recovering the source data. Each receiver, without the need to send information back to the sender, is capable of receiving the output symbols generated by some configuration chosen according to its own decoding phase. Aiming at the broadcasting scenarios without feedback channels, the proposed MC-LT codes are shown to outperform the optimal pure LT codes at the cost of encoding and transmitting units. In this paper, the inspiration of MC-LT codes is presented, how MC-LT codes work is described by giving examples, in which the optimal pure LT codes are outperformed, and a practical design of MC-LT codes, which is analytically proved to have at least the same performance bound as the pure LT codes, is proposed. The results of numerical simulation experiments demonstrate that the proposed practical design of MC-LT codes can deliver better performance than the LT codes in comparison. In summary, this paper creates new potential research directions for LT codes, and MC-LT codes are a promising variant of LT codes, especially for broadcasting scenarios. Index Terms Forward error correction, channel coding, fountain codes, LT codes, multiple configurations, broadcasting.