适用于低压电力线通信的BP译码优化方法

Decoding Optimization Method for BP in Low-Voltage Power-Line Communication

为提高低压配网电力线信道中的信息传输效率,提出一种优化BP译码的改进4折线算法。通过变换化简置信传播(belief propagation,BP)算法的校验节点信息更新函数,建立分段线性函数,并设计误差修正表对不同分段区间进行补偿,利用查表方法实现误差修正值,可降低解码实现复杂度。在Middleton A类电力线信道模型下的仿真结果表明,经分段线性函数优化后的译码算法与BP算法的误码率(bit error rate,BER)性能相近,而译码的复杂度却大大降低,有利于算法的软硬件实现,为电力线载波通信提供了一种高性能的信道编码方案。

In order to improve the information transmission efficiency in power-line channel of low-voltage distribution network, an improved 4-segment-line algorithm of channel decode was proposed, in which a piecewise linear function was established through transforming and simplifying the information update function of the check nodes of Belief Propagation（BP） algorithm, and error look-up table was designed to correct and reduce errors at different intervals, and therefore decrease the computation complexity. The simulation result under Middleton class-A model show that the bit--error-rate（BER） performance of the improved 4-segment-line algorithm is close to BP, meanwhile the decoding complexity of the proposed algorithm is greatly reduced, and it is easy for hardware and software implementatiOn. Thus the proposed decode approach can provide a high efficient ideal of channel codec for power-line communication in low-voltage grid.