Second-Order Memory Based LT Encoder Design
Second-Order Memory Based LT Encoder Design
复制标题
基于二阶存储器的 LT 编码器设计
DOI：
--
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
E. Perrins
中科院分区：
文献类型：
--
作者：
Luyao Shang;E. Perrins
提高通信可靠性和降低时延是无线多跳网络中日益增长的需求。在这方面，喷泉码已经在协作传输中被广泛采用。Luby变换(LT)码被认为是一种用于提高喷泉码族性能的基本喷泉码。以往的LT码设计工作主要集中在输出符号的度分布上，使得输入符号服从泊松分布。事实证明，通过在编码器中引入记忆，可以设计输入符号的度分布，从而提高编码性能。然而，现有的工作主要集中在基于一阶记忆的LT编码器(MBLTE)上，对于存储阶数较高时的性能没有进行研究。因此，本文研究了在二进制擦除信道(BEC)上采用BP译码的二阶MBLTE，证明了它在译码收敛速度、误码率(BER)和误码平台等方面都优于一阶MBLTE。
Increasing communication reliability and decreasing latency is an increasing demand in wireless multihop networks. In this regards, fountain codes have been widely adopted in cooperative transmissions. The Luby transform (LT) code is considered as a fundamental fountain code that is used to improve the performance of the fountain code family. Previous work on LT code design has focused mainly on the degree distribution of the output symbols, leaving the input symbols as being Poisson distributed. It has been proved that by introducing memory to the encoder, the degree distribution of the input symbols can be designed to improve the code performance. However, existing work focuses only on first- order memory based LT encoders (MBLTEs); the performance with higher memory orders is not investigated. Therefore, in this paper we study the second-order MBLTE with the belief propagation (BP) decoder over the binary erasure channel (BEC) and show that it outperforms the first-order MBLTE in terms of the decoder convergence speed, the bit error rate (BER) and the error floor.