具有快速译码收敛速度的LDPC码设计

为了提高非规则LDPC码译码的收敛速度，提出了一种具有快速收敛速度的LDPC码构造算法。该算法在原有非规则LDPC码的基础上，通过对校验矩阵进行列重排，来提升信息比特译码的可靠性，以此降低迭代次数，提高收敛速度。仿真实验表明，采用该算法设计的LDPC码，在采用基于变量节点的分层置信度传播（VL-BP）译码算法下，平均迭代次数有明显的降低。另外，对于置信度传播（BP）译码算法和VL-BP译码算法来说，设计的LDPC码具有更优的误码性能。

Design of LDPC codes with fast decoding convergence speed

Aiming at improving the convergence speed of irregular LDPC codes, a construction algorithm of LDPC codes with fast convergence was proposed in this paper. In this algorithm, by reordering the column of parity check matrix of the original irregular LDPC codes, the reliability of the information bits was enhanced, thus the average iteration times was reduced, and obtained an improvement of the convergence speed. Simulation result shows that, for LDPC codes which is designed using the proposed algorithm, the average iteration times is reduced significantly for variable-node-based layered belief-propagation(VL-BP) decoding algorithm. In addition, for both belief-propagation(BP) decoding algorithm and VL-BP decoding algorithm, the designed LDPC codes possess a better error performance.