Research On Key Technologies Of Low-voltage Powerline Carrier Communication System

Power-line carrier communication system can make full use of the existing power infrastructure, and thus has been paid extensive attention for its low construction costs, high reliability and wide coverage. With these advantages, it has been a necessary part of electric power communication. However, with the increasing number of users and the continuous expansion of new services and applications, the reliability of the power-line communication system is in great need to be improved.Based on the research and analysis of domestic and foreign scholars' study on the power-line channel model, we can see that the key to improving communication network reliability is to maintain the connectivity between source and destination despite of the dynamic channel environment.Therefore, in this paper, the following two points are put forward to settle the problem:To improve the reliability of communication between source and destination through noise suppression working on the physical layer. Based on the modeling of noises attached with the power-line, a low-complexity noise suppression algorithm using jointed blanking and robust channel estimation is proposed. The pre-blanking provides a good initial environment for the channel estimation and on the other side, the robust channel estimation helps to lower the sensitivity of blanking non-linear processing to the configuration of the threshold value. The simulation results show that, the proposed de-noising algorithm can effectively reduce the transmission bit error rate, and thus ensure the transmission success rate of the point-to-point links.To ensure the network connectivity through routing algorithm design on the network layer. Adopting the clustering routing in the Ad-hoc network, a clustering routing algorithm based on node connectivity is put forward to apply in the low-voltage power-line carrier communication system. Specifically, it includes cluster head election with nodes connectivity calculation and compare, clusters initialization, the route maintenance to update the state of connectivity among nodes, and the corresponding route reconfiguration strategy. Finally, it's verified by simulation that the proposed routing algorithm can work well to plan the path and thus reduce the packet loss rate in the network.