Study On PLC-based Information Transmission Of Intelligent Uptown

With the rapid development of the techniques of the computers, communication and networks, a low-voltage power line as the medium of information transmission is paid more attention to. Combined the techniques of the power line communication modulation and the computer networks building, a new method of low-voltage power line communication (PLC) is proposed. Its reliability and validity have been tested. The main studying aspects are the followings:1. Through the investigations and studies on the present status of the PLC application to the intelligent uptown, the feasibility and practicality of using the low-voltage power lines as the medium of information transmission have been proved. The power lines of uptown compose a self-governed power supply network that transfers energy between tenements. The network can also be regarded as a physical platform of information communication. It is a good solution to some problems that can't be solved by other networks.Because the low-voltage power lines are designed for power delivery but not for information communication, the carrier communication environment is very bad. To enlarge the signal-noise ratio (SNR), improve the information transmission reliability and reduce the pollution of the signals of the high frequencies in an electric uptown network, the advanced carrier techniques, data transmission modes, credible network structure and protocol must be adopted. Based on the studies of present power line carrier communication techniques, a modified OFDM is presented in this thesis. Through considering the uneven transmission characteristics, its impedance, noise and attenuation characteristics of a power line, an improved power line carrier communication transmission model and channel model are proposed.The network scheme and protocol, and the monitoring protocol of low-voltage power line transmission are devised, which provide certain academic and theoretical basis to the application of the PLC.A practical example validates application of the presented PLC methods in an intelligent uptown. The communication system, the management information system and the safety system of the uptown are analyzed and programmed in details. The task of the low-voltage powerline communication of intelligent uptown is significative and of long term. With the progress of society, the perfect home life of people's dream is intelligent and humanity.