Research On The Key Techniques Of Power Line Multi-carrier Communication

Power Line Communication (PLC) is a kind of data transmission technology by usingdistribution network as medium. Compared to other communication networks, the widely andintensive distributed features of distribution network make PLC has the natural advantage ofconvenient and low-cost. However, the harsh power line channel seriously affects the reliability ofpower line communication, making the early PLC technology has been difficult to achievewidespread commercial use. Therefore, the research on PLC technology applicable to the channelenvironment has great significance both in theory and application.G3-PLC based on orthogonal frequency division multiplexing (OFDM) technology, combinedwith advanced forward error correction (FEC) technology, can effectively resist the harsh power linechannel, providing a very robust and reliable PLC technology. Based on the G3-PLC specification,this paper has a research on the key technologies of multi-carrier power line communication. Themain work is as follows:1. The multipath fading and noise characteristics of power line channel is studied and thecorresponding channel simulation model is established. The G3-PLC physical layer including theframe structure, the preamble and the OFDM symbol design is comprehensively analyzed to lay thefoundation for future work.2. A symbol timing synchronization algorithm based on the local first correlation and secondarycorrelation is proposed. Also a joint realization scheme of signal detection and synchronization isgiven and shows good performance in anti multipath fading and noise interference.3. Three improved methods which are called the modified time-domain least squares(LS)algorithm, the simplified time-domain linear minimum mean square error(LMMSE) algorithm and thealgorithm based on the correlation are proposed in this paper, and all achieve good estimationperformance in lower complexity.4. The forward error correction (FEC) technology of PLC based on OFDM is studied, includinginterleaving, convolution codes and Reed-Solomon (RS) codes, etc., and a large amount of systemsimulation with various FEC schemes are carried out in different channel environment. The resultsshow that the G3-PLC can be adapted to the harsh power line channel.