Power Line Communication Route Redundancy And Network Self-healing Method For Asymmetric Channel

Low-voltage power line carrier communication channel has obvious asymmetry.Neglecting the asymmetry problem will lead to irrational route selection,low channel utilization,and low communication success rate.This paper studies the route redundancy mechanism and network self-healing method of low-voltage power line carrier communication from the perspective of identifying and using asymmetric links.Firstly,this paper analyzes the current development of power line communication technology and summarizes the protocols and standards of narrowband communication and broadband communication respectively.On the basis of comparing and discussing the medium access control protocol in each communication standard,this paper puts forward the existing protocol problems.Secondly,the characteristics of low voltage power line network are studied,and the frequency attenuation effect,multipath effect and noise characteristic of power line are analyzed from the aspects of low voltage power line network structure and transmission characteristics.The possibility of cross-band communication is discussed with the relevant measured data,breaking the constraints of conventional broadband communications and narrowband communications.Then,the existing low voltage power line media access control protocols are summarized,and the advantages and disadvantages of each protocol are analyzed.On this basis,a new medium access control protocol design requirement for large-scale power line network is proposed,which is characterized by being able to adapt to large-scale network application.In the case of expanding the network size,new protocol can still maintain a high transmission efficiency and ensure high network throughput.At the same time,solve the exposed terminal and hidden terminal problems to a certain extent.Next,we design a new media access control protocol based on time period,which can effectively reduce the probability of collision between nodes and ensure the transmission efficiency of the network by means of periodic access mechanism,priority resolution mechanism and random back-off contention.The simulation results show that the proposed new medium access control protocol is more stable and efficient in large-scale network conditions,compared to the conventional protocols.Finally,This paper studies a network self-healing algorithm that adapts to the above routing redundancy mechanism.The algorithm is designed based on different abnormal behaviors of the nodes.It can effectively and quickly maintain the network on the basis of accurately determining the abnormal conditions of the network.Simulations verify the self-healing reliability under various network damage conditions.