Design Of Systematic Network Coding Algorithm For Wireless Multi-Hop Networks

Most of the existing delay-sensitive services,such as video streaming communication,use the TCP protocol combined with ARQ technology to ensure the reliable transmission of a single packet.Nowadays,5G wireless communication has high bandwidth and can bring high speed,but its weak anti-interference ability will cause a high packet loss rate,especially in the process of long-distance transmission.Network coding,as a fusion routing and coding technology,allows the intermediate nodes to operate on the received information and then forward it,which has huge potential advantages in terms of throughput,load balancing,reliability,security,and low complexity.In order to improve the throughput of network transmission and reduce the delay,the application of systematic random linear network coding(Systematic RLNC)combined with selective repeat ARQ(SR-ARQ)protocol in single-path multi-hop wireless networks is studied in this paper.Specifically including:(1)Considering the single-path multi-hop packet loss network model,this paper proposes a network coding algorithm based on the endurance of intermediate nodes.This algorithm allows the intermediate nodes to operate the error packets they received rather than discard them directly.If the intermediate node receives the correct packet,it will store it and then forward the packet to the next node.Otherwise,all packets of the group are extracted from the cache to code,and the encoded new packet is stored and forwarded down.Based on the systematic random linear network coding and the baseline random linear network coding scheme,combined with the endurance of intermediate nodes,the algorithm is applied to a single-path multi-hop wireless erasure network,and compared with baseline ARQ and HARQ scheme under the Bernoulli channel model simulation.The proposed algorithm can nearly reach the multi-hop network capacity,and the throughput and delay performance of the network coding scheme based on the continuation of intermediate nodes is better than that of the baseline ARQ and HARQ schemes in both low and high rate scenarios.(2)Considering the abrupt continuous error channel model which is closer to the actual communication,a systematic linear network coding algorithm based on error statistics is proposed in this paper.The algorithm allows the source to determine the number of redundant packets to be added to each group of packets according to the statistics of fault packets to adapt to different link states.Compared with the uniform error distribution channel,this algorithm is more suitable for the abrupt continuous error channel.The proposed algorithm is applied to a single-path multi-hop wireless network,and is simulated on Bernoulli channel and abrupt continuous error channel.Compared with the proposed algorithm with fixed rate,the performance advantage of the proposed algorithm based on error statistics is verified.Under the abrupt continuous error model,compared with the algorithm with fixed rate,the systematic linear network coding algorithm based on error statistics has a significant improvement in throughput and delay performance.