Dynamic Channel Allocation Method And Improvement For Power Line Communication

Power line communication uses the power line of power system as a communication medium,so its convenience is unparalleled.Meanwhile,it is considered to be one of the best communication technologies in smart grid.However,the whole network of PLC shares one channel,leading to shortage of channel resources.The prevailing problem of PLC is that low schedulable utilization and long transmission delay.In order to improve channel utilization and reduce transmission delay of PLC,this thesis will research on dynamic channel allocation method.Meanwhile,this article will improve the method.Firstly,this thesis will analyze the current development of power line communication technology and communication standards and channel allocation methods.On the basis of studying PLC standards and existing channel allocation methods,this paper will put forward a new way for allocating PLC channel.The new method will combine CSMA/CA with TDMA.This method will adapt dynamic change of network load.Meanwhile,this method will improve network performance.Secondly,this thesis will show compare of advantage and disadvantage of four classic channel allocation methods.Then,this paper will focus on PRIME,a PLC standard which is exclusively used in intelligent remote meter reading system.With PRIME as a template,this article will build PLC networks.Next,this thesis will put forward a new hybrid channel allocation method which is the combine of TDMA and CSMA/CA.This method is based on dynamic TDMA,using CSMA/CA as a subsidiary.At the same time,the idea of separately control will be used in this article.When it comes to a node's slot,if that node has no requirement of transmission,it will lead to a blank slot.The blank slot will cause a waste of channel resource.With hybrid channel allocation method,blank slots can be avoided effectively.The method will contribute to improve network throughput and reduce transmission delay.With the aid of OMNe T++,this paper will build some classical PLC network.The results of simulation will show validity of hybrid method.Finally,this thesis will improve the hybrid channel allocation method.The improvement will be carried out from network layer and data link layer.As to network layer,this paper will improve transmission ability of switch nodes,using the way of load balancing.As to data link layer,this paper will focus on the problem of transmission delay,using the way of reusing time slot.This article will simulate to verify the effectiveness of improve methods.The result of simulation will show excellence of improved hybrid channel allocation method.The improved method will perform well no matter in network throughput or transmission delay.Meanwhile,the improved method will perform better than TDMA or CSMA/CA.