The Key Technology Research Of Broad Band Power Line Communications Based On OFDM

Access Network is used for the interconnection between terminal users and wide area communication network by which users can get various communication services. However, the cost of implementation, installation and maintenance of access network is quite high. Thus, in condition of ensuring the normal communication, network operating business always implements layout of the access network with low cost as they can to improve their competition capability.Techniques of Power Line Communication provide a very promising solution scheme for the implementation of access network. Technique of band access that is thought of having an optimistic prospect is a communication method that transfers high-speed data, voice and images through low-voltage lines of distribution network. With the fast development of Internet, it is attached more and more importance on the value of transferring high-speed data by 220V low-voltage lines. Because of its obvious characteristic such as no necessity to layout, wide coverage area and convenient connection, it is thought as one of the most competitive techniques among the solution schemes.First, this paper introduces the concept and application prospect of communication by power line carrier, and researches the basic features of power line communication channels and its module is established. Then based on the features of power line channels, a power line communication system based on OFDM is presented. In this system, reasons for high PAPR is analyzed emphatically and tone reservation, a controlled trimming algorithm is presented which is an improved carrier method for lowering PAPR effectively. By large amount of data simulation, the feasibility of the algorithm is proved.