Research On Transmission Mechanism In Deep-Space Network Based On Network Coding And Dynamic Redundancy

Due to the characteristics of high bit error,extreme long time delay and bursty packet loss,which are different from terrestrial network,the existing transmission mechanisms are difficult to meet the requirements of high efficient transmission in deep space network.To deal with the characteristics of the deep space network,this paper studies the deep space network transport mechanism by introducing network coding technology,and due to the bursty packet loss characteristic in deep space network,this paper also propose a block coding combination mechanism,our work is as follows:First,we make a comprehensive analysis on research status in deep space network transmission,summarize the transmission optimization technology to deal with the problems of bit error and long transmission delay,discuss the research status of deep space network transmission protocols and analyze their shortcomings,which lead to the research of our work.Secondly,we apply network coding technology to deep space network transmission and propose a deep space network transmission mechanism NCSTP.In NCSTP,the sender side adds redundant coded packets in the sending sequence of original packets in a reasonable manner according to the packet error rate,and the receiver side generate the lost original packets by decoding the redundant coding packets.In this way,it can avoid the time consuming of retransmission.Thirdly,because of the characteristics of bursty packet loss in deep space network,this paper propose a block coding combination mechanism by combining coding blocks in a reasonable manner.In this mechanism,we calculate the block coding coefficient 9)according to the link error rate,which is the number of blocks need to be grouped together,the sender side combine 9)coding blocks into one combination block based on the block coding coefficient 9),and generate corresponding 8)(8)>= 9))redundant coding packets.When bursty packet loss happens in a combination block and some packets are lost in a short time,as long as the number of lost packets is smaller than 8),the receiver side can generate the lost packets using the 8)coding packets of the block,so as to deal with bursty packet loss problem.Finally,we test and analyze the performance of the mechanism on a simulation platform.In this paper,we build a network topology simulating the deep space network on the simulation platform,and test the performance of the two mechanisms in the topology.After comparison and analysis,we make conclusions.