电力线传输特性和噪声干扰对通信性能的相对影响

电力线载波通信技术是支撑智能电网信息传输的重要技术之一，但是电力线作为信息传输通道时具有复杂的传输特性和较多的噪声干扰。为分析电力线信道的频率选择性对通信性能的影响及其和信道噪声的相对作用，设计滤波器模拟具有不同频率选择性的电力线信道，用米德尔顿A类噪声模拟信道中不同强度的噪声，采用基于OFDM技术的G3-PLC标准建立窄带电力线载波通信系统模型进行仿真分析。结果表明：电力线载波通信中，低速率传输数据或信号带宽较小时噪声干扰比频率选择性对系统性能影响大。随着数据传输速率或信号带宽增加，信道的频率选择性对系统性能的影响逐步增大。该结论为设计和研究电力线载波通信系统提供了理论分析基础。

Relative impacts of channel characteristics and noise characteristics on the performance of a power line communication system

Power line carrier communication (PLC) technology is one of the important technologies supporting information transmission for the smart grid. As an information transmission medium, however, a power line is complex in terms of its channel and noise characteristics. In order to disentangle the relative influence of channel frequency-selective fading and channel noise on the performance of the PLC system and the interaction between them, filters are designed to simulate power line channels with different frequency-selective fading and Middleton Class-A noise is used to simulate the noise of different intensities in the PLC system. Based on the G3-PLC protocol, which adopts OFDM technology, a whole model of the narrowband PLC system is built and simulation analysis is conducted. Results show that the noise characteristic has more influence on performance than frequency-selective fading in conditions of low transmission rate and/or small signal bandwidth. With the increase of transmission rate and/or signal bandwidth, the influence of channel frequency selectivity on the system performance becomes more significant. The results of this study provide a theoretical basis for designing and studying the PLC system. This work is supported by the National Natural Science Foundation of China (No. 51974151).