Liu Gaosai, Jiang Xinglong, Li Huawang, Zhang Zhenhua, Sun Siyue, Liang Guang
Innovation Academy for Microsatellites of CAS, Shanghai 201204, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Sensors (Basel). 2022 Aug 11;22(16):5995. doi: 10.3390/s22165995.
The traditional satellite access selection algorithm, which is used in large-scale satellite networks, has some disadvantages, such as frequent link switching, high interrupt probability, and unable to adapt to a dynamic environment. According to the periodicity of the large-scale satellite network and the prior knowledge provided by acknowledgment packages, a dynamic domain-based adaptive access algorithm (DAA) is proposed in this paper. Firstly, this algorithm divides the large-scale satellite network into different domains according to the minimum elevation angle of the Earth station (ES) and the predictable characteristics of the trajectory of the satellite. Then, the ES selects the access satellites according to the relationship between the traffic volume and the satellites' coverage time. Finally, the ES selects the backup access satellite based on the satellites' coverage time, the traffic volume of the ES, satellite status provided by prior knowledge, and other information. When the access satellite cannot satisfy the communication demand, the ES adaptively switches the earth-satellite link to the backup access satellite. The ES first choice of access satellite does not require interaction with the satellites, reducing the consumption of communication resources. The selection strategy of backup access satellite and the concept of virtual destination address proposed in this paper can reduce the routing overhead after switching. Through theoretical analysis and simulation results in the StarLink constellation, it is proved that this paper improves the coverage time utilization of accessing satellites and reduces the switching probability compared with the traditional access algorithm, which is more suitable for ES to access large-scale satellite networks.
传统的卫星接入选择算法应用于大规模卫星网络时存在一些缺点,如频繁的链路切换、高中断概率以及无法适应动态环境。根据大规模卫星网络的周期性以及确认包提供的先验知识,本文提出了一种基于动态域的自适应接入算法(DAA)。首先,该算法根据地球站(ES)的最小仰角和卫星轨迹的可预测特性将大规模卫星网络划分为不同的域。然后,地球站根据业务量与卫星覆盖时间的关系选择接入卫星。最后,地球站基于卫星覆盖时间、地球站业务量、先验知识提供的卫星状态等信息选择备用接入卫星。当接入卫星不能满足通信需求时,地球站将地星链路自适应切换到备用接入卫星。地球站对接入卫星的首次选择无需与卫星交互,减少了通信资源消耗。本文提出的备用接入卫星选择策略和虚拟目的地址概念可降低切换后的路由开销。通过在星链星座中的理论分析和仿真结果表明,与传统接入算法相比,本文算法提高了接入卫星的覆盖时间利用率,降低了切换概率,更适合地球站接入大规模卫星网络。