Research On Protocols Of The Data Link Layer For Broadband PLC Networks

Broadband power line communication(BPLC)is a wired communication technology that uses low-voltage power distribution lines as an information transmission medium and can transmit voice or data at a rate of up to Mbps.The network using BPLC technology has the natural advantage of not needing to re-establish the network infrastructure.The basic frequency band of BPLC network is 1MHz ～ 20 MHz.Compared with the traditional narrowband power line carrier communication,the BPLC network has a wider communication bandwidth,higher transmission rate and stronger anti-interference performance.At present,based on the international standard IEEE 1901.1 in the field of BPLC and standard documents such as Q/GDW 11612 of the State Grid Corporation of China,BPLC technology has been developed by leaps and bounds.At present,BPLC has been widely used in various occasions such as energy internet,automatic meter reading,intelligent power system,street light control,charging pile construction and so on.First of all,this thesis introduces the research background and current research status of power line communication networks,as well as the concept,characteristics and application scenarios of BPLC networks.Afterwards,this thesis introduces the principles of BPLC network data link layer networking,network maintenance,and channel access.Then,this thesis classifies and narrates the existing BPLC network networking protocols,and also analyzes the challenges faced by the current BPLC network networking protocols.Secondly,in view of the redundancy problem in the number and time of the existing BPLC network networking protocol in reply to the association confirmation message,combined with the characteristics of the BPLC network access protocol,an efficient networking protocol based on adaptive multicast is proposed.By adaptively aggregating association confirmation messages and sending them in a multicast manner,the protocol reduces control overhead while speeding up the sending of partial association confirmation messages.Theoretical analysis proves the validity of the agreement.OPNET software simulation results show that compared with the existing BPLC network networking protocol,this protocol can reduce the control overhead by more than 5.88%and the network access delay by more than 5.53%.Then,aiming at the problem of the unbalanced topology of the existing BPLC network,an optimal relay selection algorithm for broadband power line communication networks is proposed.Firstly,the algorithm selects a path with the highest success rate from all paths from the network application node to the central controller,so that the node selects the most reasonable relay node.Then,the algorithm uses the beacon message delivery rate to record the communication status between nodes,so that the distribution of nodes is more balanced.Finally,the algorithm establishes an inverted V-shaped transfer strategy with a public relay node as the top node,which improves the efficiency of data transmission.The simulation experiment results show that the algorithm is superior to the existing technology in terms of average end-to-end delay,data transmission success rate,and network throughput.Finally,this thesis summarizes the full text of the work,and looks forward to the direction that the BPLC network can break through in the future.