Study On Network Coding-based Routing Algorithms For Wireless Sensor Networks

Wireless sensor networks as one of the research hotspots today,it can collect,process and transmit all kinds of information in the network monitoring area,and finally transmit the information to the owner of the network.However,in the process of data transmission,due to the limited energy of wireless sensor nodes and the instability of wireless links,the performance of wireless sensor networks is greatly affected.The technology of network coding was first proposed by R.Ahlswede and others at the beginning of this century.Network coding is a new way of data transmission,nodes in the network can first encode the received packets into a coding package,and then forward them to the next hop node,increasing the throughput of the entire network by increasing the amount of information in single forwarding.Therefore,the application of coding technology to wireless sensor networks can enhance the effectiveness of data packet transmission,reduce energy consumption and prolong network lifetime.This article first summarizes the related research background and technology of the subject,then introduces and analyzes the current routing algorithms of WSN based on network coding,and put forward two kinds of wireless sensor network routing algorithms based on network coding,the main work and achievements are as follows:1.To deal with the problems that how to balance the energy consumption of nodes and prolong the lifetime of network in energy-efficient reliable opportunistic routing algorithm which based on network coding(EROR)for wireless sensor networks,an optimized opportunistic routing algorithm based on network coding(ORNC)was proposed.In the ORNC algorithm,mainly proposed four kinds of improved mechanism:Firstly,taking the channel bit error rate and packet loss rates to calculate the failure probability of nodes receive the encode packets,reducing the retransmitted number of encode packets;Secondly,the node in the forwarding set broadcast the cost packet directly instead of ACK packet when it collect enough encode packets,reducing the network overhead and the waiting time of primary forwarding nodes.Thirdly,the neighbors of the primary forwarding nodes update their own forwarding cost based on the received cost packet,then decide whether to become assistant forwarding node,this scheme can prevent the neighbors with large forwarding cost from forwarding encode packets;Fourthly,the cooperative nodes will use its cached information to calculate the number of sending coded packets,reduce the extra cost.2.To solve the problems of cluster-level multipath routing algorithm based on network coding(NCCM)in the process of forming forward node set,including excessive judgment messages sent by nodes,which causes excessive network overhead.as well as in the selection of cooperative nodes without considering the link quality between cooperative nodes and the downstream nodes,it will result in too many retransmissions of data packets,this paper proposes an efficient cooperative routing algorithm based on network coding(ECNC).In the route discovery phase,this algorithm not only refers to the link quality but also considers the residual energy of each node on the link,prevent the nodes with low energy from sending data packets frequently,prolong the lifetime of network.In addition,the cooperative forwarding node will be determined according to the link quality of upstream routing node neighbors and downstream routing nodes,reducing the number of packets retransmission and nodes energy consumption.Finally,summarize this thesis and give the further research directions.