中文摘要：

电力线通信中的A类噪声模型使用LDPC码不仅可以有效抑制窄带脉冲噪声，还能通过简单有效的译码算法降低实现复杂度，提高数据传输质量。经过对LDPC的几种常用译码方法进行了分析研究，发现归一化最小和算法中的修正因子在电力线信道下是可以进行优化选择的。通过系统仿真和数据比较，结果表明，在对A类噪声模型的参数Г和A取值合理的情况下，优化后的归一化最小和算法在误码率上性能接近标准BP算法，复杂度得到了降低。

英文摘要：

By using LDPC in the class A Middleton＇ s model for the power line communications, the narrowband impulse noise could be effectively suppressed, the implementation complexity reduced, and thus the quality of data transmission improved with simple and efficient decoding algorithm. Based on analysis of several common LDPC decoding algorithms in the power line channel, it is found that the correctional factor of normalized minimum-sum algorithm in the power line channel could be optimized and selected. Simulation results show that the optimal normalized minimum-sum decoding algorithm is quite close to the standard BP decoding algorithm in performance with properly-selected values of A and Г.