Research On Inter-satellite Link Cross-layer Routing Algorithm

As the traditional terrestrial communication network can no longer meet people's demand for information acquisition and transmission,the research of satellite communication technology has drawn the attention and great development of professionals both at home and abroad.Because of its global coverage,flexible global network configuration and global broadcast information,satellite mobile communication network can realize multi-dimensional information transmission mechanism so as to provide feasible service for global coverage of communication network and promote global network Development.Low Earth Orbit(LEO)satellite communication system has the advantages of low altitude,star ground,good inter-satellite link performance and low transmission delay,and the LEO satellite is small in size and relatively low in cost.Therefore,in the current study of satellite communication networks,the main choice is the LEO orbit height.In this paper,the advantages of low-orbit satellite inter-satellite link,the main study of the satellite communication process of inter-satellite link routing algorithm.This paper firstly discusses and explains the LEO satellite communication system as a whole.Based on the research on the current research status of the key technologies of LEO satellite communication in the industry and academia at home and abroad,this paper focuses on the research on the routing technology of LEO satellite inter-satellite link,and makes innovations and improvements based on the existing research.An improved routing algorithm based on adaptive modulation and coding is proposed,as well as A QoS routing strategy based on delay constraint is proposed.Aiming at the inter-satellite routing strategy of fixed transmission rate,this paper considers the data transmission rate of cross-layer analysis and proposes an improved routing algorithm based on adaptive modulation and coding.This algorithm is suitable for data transmission scenario of LEO satellite inter-satellite link.In this algorithm,an adaptive modulation and coding scheme is applied to the channel model of LEO satellite inter-satellite link,and a routing algorithm under the influence of information transmission rate is proposed.In the inter-satellite link channel model,free space path loss in space orbit of LEO satellite system is considered as additive white Gaussian noise,and the modulation coding mode and information transmission rate under the influence of inter-satellite distance are analyzed.In the routing strategy,the reciprocal of information transmission rate is proposed as the weight of propagation delay,and the minimum propagation delay is used as the minimum hop index,and a detailed performance analysis including propagation delay and throughput is carried out.For the congestion control strategy of the inter-satellite link,this paper first analyzes the traffic distribution rules based on the coverage area.It is a discrete time function limited by geographical factors,economic factors and time factors,and changes cyclically.Secondly,the delay constraint model is established,considering the intra-link delay,the inter-link delay and the queuing delay as the total delay constraints.Based on the delay constraint model,the first N shortest paths are generated.Finally,QoS impact factors are considered respectively:end-to-end delay,packet loss rate and delay jitter.Compared with DRA,the shortest path algorithm based on delay constraint DSPF),which is suitable for traffic congestion processing scenario of LEO satellite inter-link,which performs better in the path selection strategy.When the business is congested,the end-to-end delay is shorter,and the delay jitter is more stable.In this algorithm,the first N shortest paths of a delay constraint are calculated into the routing table of the low-earth orbit link,so a best path strategy based on QoS is achieved.