北斗区域系统PDOP可用性状态更新与仿真分析  

State Updates and Simulation Analysis of PDOP Availability for Bei Dou Regional System

作　　者：张天桥 王宏兵 牛飞 ZHANG Tian-qiao WANG Hong-bing NIU Fei(Beijing Satellite Navigation Center, Beijing 100094, China)

机构地区：[1]北京卫星导航中心,北京100094

出　　处：《无线电工程》2017年第2期52-56,共5页Radio Engineering

基　　金：国家自然科学基金资助项目(41304031)

摘　　要：服务可用性是卫星导航服务指标体系中的基本要素,是系统运行阶段性能测试评估的重点之一。研究了影响卫星导航服务可用性指标的几个关键问题,提出了基于单星可用性、测距误差和用户使用条件等多重约束下的服务可用性计算表达公式。依据北斗公开服务性能规范中的概念描述,给出了不同于GPS SPS的服务可用性精度门限概念。基于全概率计算公式,针对北斗区域系统新增第1颗备份卫星前后,北斗区域服务可用性进行了比较性计算分析。仿真评估结果表明,增加北斗第1颗备份星后,北斗区域服务可用性将由1.0版服务性能规范中所定义的98%提升至99%以上。Availability is a basic element in the service specification for navigation satellite systems,and is also one of the key system performance indicators to be assessed in the operational phase. In this paper, some key problems in the design of satellite navigation service availability are introduced firstly. Then, a calculation formula of service availability is proposed based on multiple constraints such as single satellite availability,ranging error and user operating conditions.According to the concept specified by BeiDou open service performance standard,an accuracy threshold for the service availability is established which is different form the GPS SPS. Finally,comparative calculation analysis is made for the first in-orbit spare BeiDou satellite, pointing out the service availability difference before and after this satellite is launched.Simulation and evaluation results show that after the first BeiDou backup satellite is added to the system, the service availability of BeiDou regional system will increase to 99% from 98% defined in BDS service performance standard Version 1.0.

关 键 词：卫星导航 服务可用性 定位几何精度因子 北斗服务性能规范 卫星故障概率 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]