基于信道认知在线可定义的电力线载波通信方法

On(Power-) Line Defined Power Line Communication Solution Based on Channel Sensing

常规的电力线载波技术在规定的频带范围采用固定的工作频率通信,不能适应复杂、时变、差异性的电网信道特性,通信性能和业务保障差。为提高面向智能电网应用的电力线载波通信技术的可靠性、灵活性与覆盖率,满足智能配用电业务通信需求,提出一种基于信道认知在线可定义的电力线载波通信方法,使载波通信可根据中低压配电网电力线信道实际情况,在150 k Hz^10 MHz跨频带范围内自适应选择合适的工作频率和通信带宽。从而打破传统电力线载波通信工作频率窄带和宽带的分割,实现基于信道认知结果的电力线载波通信参数"在线定义"。在给出所提出方法实现架构的基础上,着重探讨基于等效复数基带和收发端双加窗的数字前端、基于无线电信号接收因子的中短波电台检测、以及前导序列辅助下的频率选择等关键技术。仿真和现场实际测试证明了所提电力线载波通信方法的有效性,通过节点自主认知信道环境并自适应选择工作频率,提高了载波通信链路的可靠性和单跳覆盖率,对未来电力线载波技术在智能电网中的应用具有推动作用。

Conventional power line communications （PLC） use the fixed working frequencies in the pre-defmed spectrum band. It ignores the complicated, time-varying and differential power line channel characteristics, which leads to the low communication performance and weak service assurance. For smart grid applications, PLC needs to improve its reliability, flexibility and coverage in order to satisfy the emerging communication requirements. This paper proposed an on （power-） line defined PLC solution based on channel sensing, which entails PLC nodes to on-line determine their proper working frequency and communication bandwidth within 150 kHz-10 MHz that fit their specific channel conditions. The proposed solution exceeds the traditional narrowband and broadband frequency separation of PLC, and makes the communication parameters be efficiently on-line defined according to the channel sensing results. Apart from its implementation architecture, this paper mainly discussed its key components, including the digital front-end （DFE） design combined with equivalent complex base-band （ECB） and windowing technique, the detection method of medium/short wave radio stations based on radio reception factors, as well as the preamble assisted frequency selection scheme. Simulations and field tests confirmed the effectiveness of the proposed solution. By sensing the channel autonomously and selecting the working frequency adaptively, the proposed solution can establish reliable communication links and enhance the single-hop coverage, which will promote the future applications of PLC in smart grid.