Power lines present a more challenging communication environment compared to other media. Impedance mismatches and network branches render the channel frequency‐selective, leading to strong inter‐symbol interference (ISI). Moreover, devices connected to the power grid introduce impulsive noise on the network. Such factors may degrade the system performance drastically. Therefore, robust coding and modulation schemes are required to increase the communication reliability. Furthermore, multiple access communication allows many users to share a common medium to enhance the systems' throughput. This paper examines the behaviour of two schemes, turbo codes and multi‐fold turbo codes, against a two‐user adder channel under power‐line conditions operating below 500 kHz. Both schemes employ distinct codes for each user and make use of orthogonal frequency‐division multiplexing (OFDM) to cope with the ISI. Three configurations of a low‐voltage (LV) power‐line outdoor network are considered. Results obtained through simulations show that a gain, up to 3 dB, can be obtained for both users using the multi‐fold turbo coding over the conventional turbo coding. The effect of iterative decoding on the performance of both schemes is also reported.

中文翻译：

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在两个用户的窄带电力线二进制加法器通道上使用多重Turbo码减轻循环平稳噪声

与其他媒体相比，电力线呈现出更具挑战性的通信环境。阻抗不匹配和网络分支使信道具有频率选择性，从而导致强烈的符号间干扰（ISI）。此外，连接到电网的设备会在网络上引入脉冲噪声。这些因素可能会严重降低系统性能。因此，需要鲁棒的编码和调制方案来增加通信可靠性。此外，多址通信允许许多用户共享一个公共介质，以提高系统的吞吐量。本文研究了在低于500 kHz的电力线条件下，针对两个用户加法器通道的两种方案的行为，即Turbo码和多重Turbo码。两种方案都为每个用户使用不同的代码，并利用正交频分复用（OFDM）来应对ISI。考虑了低压（LV）电力线户外网络的三种配置。通过仿真获得的结果表明，与传统的turbo编码相比，使用多重turbo编码可以为两个用户获得高达3 dB的增益。还报告了迭代解码对两种方案的性能的影响。