Research On Efficient Information Transmission Method Of Large-scale Micro-nano Satellite

Micro-nano satellites have developed rapidly in the fields of observation,reconnaissance,communications,navigation,remote sensing,and scientific research due to their small size,light weight,low cost,multiple functions,and flexible netw orking.In recent years,with the development of space technology and the growth of user demand,the number of micro-nano satellites has increased.However,with thousands of micro-nano satellites operating in space,the massive amounts of data information generated cannot be effectively transmitted through ground stations or space-based networks.Aiming at the problem that it is difficult to achieve efficient transmission of massive information in large-scale micro-nano satellite communication scenarios,this thesis proposes a new and efficient micro-nano satellite network clustering algorithm,and designs intra-cluster and inter-clusters multiple access protocol for clustering networks.The research content and innovations of this thesis are as follows:This thesis summarizes the current development status of satellite network communications,analyzes the challenges of massive information transmission based on ground stations,loworbit constellations,or high-orbit satellites,and points out that clustered transmission can effectively increase the data amount downloaded from micro-nano satellite.Meanwhile,the characteristics and effectiveness of typical clustering transmission technology and multiple access technology are analyzed,which provides the support for designing efficient information transmission methods in large-scale micro-nano satellite networks.Aiming at the low efficiency of massing information transmission in large-scale micro-nano satellite communication networks,a clustering algorithm that supports the efficient transmission of massive information is proposed.By clustering micro-nano satellites,cluster head satellites are used to gather remote sensing data and control commands of satellites in the cluster to reduce the probability of conflicts in information transmission,improve the utilization ratio of communication resources and network throughput,and reduce the endto-end latency.This thesis establishes a micro-nano satellite random access model based on a two-dimensional Markov chain,which can depict the characteristics of the satellite network multiple access process without carrier sensing mechanism.Deriving the micronano satellite network throughput under the access mechanism.With the optimization goal of maximizing the network throughput,a micro-nano satellite network clustering algorithm is designed,which can obtain the optimal number of clusters according to the link rate,the network size,and the traffic arrival rate.Specifically,the clustered network and the nonclustered network are compared and analyzed through simulation.Simulation results show that with the increase of the scale of micro-nano satellite network and the rising of the traffic arrival rate,the clustered network reduces the average delay and improves the information transmission efficiency compared with the non-clustered network.A satellite network multiple access protocol based on clustering is designed to support efficient information transmission of polling within clusters and competition between clusters.The protocol includes the signaling interaction process of the cluster establishment phase,cluster maintenance phase,and data transmission phase.Designing the frame structure of management frame,control frame and data frame involved in the signaling and data interaction process.Constructing the state transition process of the nodes in the cluster and the cluster head node during the access process.With the proposed clustering algorithm,the protocol can dynamically adjust the number of clusters according to different traffic arrival rates of micro-nano satellites,keeping the system throughput within the maximum range.