基于马尔可夫过程的GNSS星座可用性评估

卫星导航的星座可用性是评价导航系统性能的重要指标之一。基于马尔可夫过程建立了同时考虑卫星故障率和修复率的单星可用性模型,结合卫星的备份情况提出了空间信号层和服务层的星座可用性评估方法模型。基于上述评估模型,结合大量实测数据分析了空间信号层和服务层的星座可用性概率。结果表明:全球定位系统(global positioning system, GPS)星座可用性评估模型是有效的,GPS星座可用性符合其系统性能规范。提出的星座可用性评估方法对北斗卫星导航系统的全球化建设及其可用性评估有一定的参考价值。

GNSS constellation availability evaluation method based on Markov chain

The constellation availability of satellite navigation system is one of the important indexes when evaluating the satellite navigation system performance. The satellite availability model based on Markov chain is set up, and the satellite failure rate and repair rate are taken into account in the model. Moreover, the signal in space (SIS) and service constellation availability evaluation models are proposed by combining with the backup satellites. According to the real measured data of global positioning system (GPS), SIS and service constellation availability are verified. The results demonstrate that the proposed evaluation models are effective and the performance conform GPS performance standards. Meanwhile, the satellite availability and constellation availability evaluation methods are instructive for the study of globalization construction and availability evaluation of BeiDou navigation satellite system.