分析了应用于铁路、内河水运等领域的分布式区域卫星导航系统通信协议时延。为保障中心站信息的及时传输,采用排队优先权站点门限服务轮询方式共享信道。通过内嵌马尔科夫链的方法,推导出了中心站和一般站的分组平均等待时延,仿真结果验证了理论分析的正确性。理论分析和仿真表明中心站平均等待时延远小于一般站时延,当一般站个数较多时尤其明显。
The communication protocol delay of distributed area satellite navigation system is studied for railway and inland river transport. The queueing priority gating station polling protocol is used for satisfying the center station delay requirement. By the imbedded Markov chain method, the packet mean waiting delay of the central station and the general station are obtained. The formula was verified by simulation. According academic analysis and simulation, the center waiting delay is far less than the general station, especially with much more general stations.