随着卫星技术和通信技术的发展,由全功能大型卫星组成的卫星星座网络正逐渐被由大量微小型卫星组成的分布式自组织星群网络所替代.这种新型卫星网络架构给星间数据通信和路由带来了自组织、自适应能力方面的问题.本文从延迟容忍的角度考虑,提出利用卫星周期性运动的特点构建网络结构,建立联系图来计算和选择路由.针对异常情况,采用被动发现和重路由机制重构网络拓扑,并利用满消息和空消息的传递来避免拥塞和控制流量.使用OPNET搭建网络仿真场景,分析对比该方案的性能.实验结果表明:与Flood路由、Spray-and-wait路由、Random路由相比,本文提出的路由技术具有更高的抗毁性能,且在平均端到端时延上从2 377 s降到16 s,平均吞吐量上从1 696 bit/s提高到2 895 bit/s.%With the development of satellite and communication technology,constellation networks are gradually replaced by distributed self-organized swarm networks,which accordingly leads to the revolution in satellite networks from full-functional large satellites to a large number of micro satellites.This new architecture of satellite network brings new challenges on self-organization and self-adaptation to inter satellite communication and packet routing.From the perspective of delay tolerant network,this paper proposes to utilize the periodic motion of satellites to construct the network topology,and establish contact graphs among satellite nodes to compute and choose routing paths.To cope with exceptional situations,the passively discovering and rerouting mechanism is designed to reconstruct the network topology,and two types of messages (Full/Empty) are employed to avoid congestion and control traffic.The performance of proposed routing algorithm is evaluated and compared with existing work by using the OPNET network simulator.The experiment results show that this new algorithm is more capable of resisting disruptions,and decreases average end-to-end delay from 2 377 s to 16 s,increases average throughput from 1 696 bit/s to 2 895 bit/s,compared to the Flood,Spray-and-wait and Random algorithms.
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