多层中继网络上的分布式LT码

目前对分布式LT码(DLT)的研究仅限于信源数量较少、且只有1层中继的情况，该文提出一种能够部署在多层中继网络上的分布式LT码，即多层分布式LT码(MLDLT)。该码将信源进行分组，将中继进行分层，通过分层后的中继群，可以将多达几十个乃至上百个信源连接到同一个接收端，从而实现众多信源通过多层中继对同一个接收终端的分布式LT码通信。通过对MLDLT码进行与或树分析，得出其中继度分布的线性优化方程。分别在无损和有损链路上计算该码的渐进性能并进行数值仿真，结果证明MLDLT码在无损和有损链路上的错误平台都比较低。MLDLT码非常适合于信源数量较多的多层中继网络。

Distributed LT Codes on Multiple Layers Networks

Present researches on Distributed Luby’s Transmission (DLT) codes are restricted on several-sources and one-layer-relay networks, thus the Multiple Layers Distributed LT (MLDLT) code for multiple-layers-relays networks is proposed. In MLDLT, sources are grouped and realys are layered in order that scores of sources can be connected to the only destination through the layered relays. By this scheme, the distributed communication between scores of sources and the destination can be performed. Through the and-or tree analysis, the linear procedures for the optimization of the relays' degree distributions are derived. On both lossless and lossy links, asymptotic performances of MLDLT are analized and the numberical simulations are experimented. The results demonstrate that MLDLT can achieve satisfying erasure floors on both lossless and lossy links. MLDLT is a feasible solution for the scores-sources and multiple-layers-realys networks.