利用空间耦合LDPC码的双向软信息中继方案

Bidirectional soft information relaying scheme via spatial coupling LDPC coding

摘要:

为研究低信噪比区域中继节点解码过程的误差影响，提出一种基于空间耦合低密度奇偶校验 (SC-LDPC) 码的双向软信息中继方案，以及一种精确度更高的模型以描绘软符号上的残留噪声特征.提出的方案在目的节点使用了一个预先计算的查找表，使得残留噪声比例因子和软误差方差的计算更加简便.与以往的软噪声建模技术相比，提出的方案降低了信令开销.另外，为修正目的节点处的等效噪声方差，引入了方差修正因子.仿真结果表明：与其他同类方案相比，提出的中继方案在误比特率方面取得了明显改善.

Abstract:

In order to study error influence of relaying nodes decoding process in which the signal to noise ratio is low, bidirectional soft information relaying scheme based on spatially coupled low density parity check (SC-LDPC) is proposed, and a more accurate model is also presented to describe the residual noise characteristics of the soft symbol. The proposed scheme adopts a pre-computing look-up table at the node of destination, which makes the calculation of the residual noise scale factor and the soft error variance more convenient. Compared with the previous soft noise modeling techniques, the proposed scheme reduces the signaling cost. In addition, the variance correction factor is introduced to correct the equivalent noise variance at the destination node. Simulation results show that, compared with other similar schemes, the proposed scheme achieves a significant improvement in bit error rate.