摘要
针对星基增强系统(SBAS)用户差分距离误差(UDRE)完好性参数评估时双频无电离层组合放大观测噪声的问题,提出伪距域完好性评估方法,该方法反映了SBAS电离层改正数和星历时钟改正数的综合影响。利用240天共100个国际全球导航卫星系统(GNSS)服务组织(IGS)测站的数据对美国广域增强系统(WAAS)和欧洲地球静止轨道导航重叠服务(EGNOS)的性能进行评估。结果表明:WAAS和EGNOS格网电离层垂直误差(GIVE)参数的完好性分别为99.96%和99.91%,电离层延迟改正精度达到0.56 m。WAAS和EGNOS伪距域完好性优于99.999%,经改正后的GPS用户测距误差(URE)精度达到0.34 m。WAAS 95%的水平和垂直定位误差为1.19 m和1.72 m,EGNOS的则为1.18 m和1.68 m。评估时段内均未发生完好性风险事件,验证了测地型接收机用于SBAS服务性能评估的可行性。WAAS在一类垂直引导进近(APV-I)阶段的定位精度平均可用性为99.9%,二类垂直引导进近(APV-II)阶段在服务中心区域的定位精度可用性为80%~95%;EGNOS APV-I阶段平均定位精度可用性为99.9%,APV-II阶段平均定位精度可用性为94.2%,可用性较高,主要是由于EGNOS评估测站多处于服务区中心。SBAS定位精度可用性在服务区边缘部分下降较明显。
Dual frequency ionosphere-free observations are usually applied to evaluate the satellite based augmentation system(SBAS)user differential range error(UDRE)integrity with the drawback of noise amplification.Instead,a range domain integrity method is proposed to assess the combined effect of SBAS ionospheric corrections,ephemeris and clock corrections.240 days data of from 100 international global navigation satellite system(GNSS)service(IGS)stations are employed to evaluate the service performance of wide area augmentation system(WAAS)and European geostationary navigation overlay service(EGNOS).Results show that:The grid ionospheric vertical error(GIVE)integrity of WAAS and EGNOS achieves 99.96%and 99.91%respectively and the accuracy of ionospheric correction is 0.56 m.The range domain integrity of WAAS and EGNOS is better than 99.999%and the GPS user range error(URE)after applying the corrections achieves 0.34 m.For WAAS,the 95%horizontal and vertical positioning error is 1.19 m and 1.72 m,whereas for EGNOS,it is 1.18 m and 1.68 m.During the test,there were no integrity risk events.It is confirmed that it is feasible to evaluate the SBAS performance—particularly the integrity—using a geodetic receiver.The average availability of positioning accuracy for WAAS during approach with vertical guidance I(APV-I)is 99.9%,while for approach with vertical guidance II(APV-II),it ranges from 80%to 95%within the center of the service area.The average availability of positioning accuracy for APV-I of EGNOS is 99.9%,and for APV-II,it is 94.2%,indicating a higher level of availability,largely because most of the EGNOS assessment stations are located in the center of the service area.The SBAS availability noticeably decreases at the edge of the service area.
作者
金彪
李锐
王盾
刘磊
原晋栩
李子潇
JIN Biao;LI Rui;WANG Dun;LIU Lei;YUAN Jinxu;LI Zixiao(Space Star Technology Co.,Ltd.,Beijing 100095,China;Electronic Information Engineering,Beihang University,Beijing 100191,China;Seventh Military Representive Room of Air Loading Beijing,Beijing 100076,China)
出处
《北京航空航天大学学报》
EI
CAS
CSCD
北大核心
2024年第10期3062-3073,共12页
Journal of Beijing University of Aeronautics and Astronautics
基金
国家自然科学基金(41974041)。
关键词
星基增强系统
格网电离层垂直误差
伪距域
完好性
可用性
satellite based augmentation system
grid ionospheric vertical error
range domain
integrity
availability
