摘要
星座可用性指标是在用户层面上反映星座工作状态的重要指标。随着卫星在轨运行时间的增加,卫星的可靠性会不断降低,星座可用性也会随之下降。在考虑卫星故障概率的条件下,本文提出综合运用贝叶斯网和马尔科夫链进行星座可用性分析的方法,剖析了导航星座中卫星故障与导航应用服务中断之间的相互关系,简化了星座可用性的建模过程。结合中断分析数据,量化评估了星座可用性,并利用灵敏度分析找出星座薄弱环节。该方法可为导航星座设计方案优化权衡提供量化依据。
The constellation availability is an important performance index which can reflect the system performance by user perspective.However,the reliability of a satellite and the availability of the constellation will both be lowered gradually while satellite on-orbit operation time increases.Under the condition of considering the satellite failure probability,a new method of integrating Bayesian network and Markov chains is presented in order to enhance the constellation availability.By analyzing the relationship between satellite fault and navigation service outage,the modeling process of the constellation availability is simplified properly.Taking the outage data as the model input,the constellation availability can then be evaluated quantitatively,and the key satellite of the constellation can also be identified through sensitivity analysis.Moreover,the simulation results show the quantity proof for the constellation design optimization.
出处
《航天控制》
CSCD
北大核心
2011年第3期87-90,94,共5页
Aerospace Control
基金
国防科研基金项目(Z032009B001)
关键词
导航星座
可用性
贝叶斯网
马尔科夫链
Navigation constellation
Availability
Bayesian network
Markov chains
