CN111983641B - 一种用于实时生成北斗星基增强系统完好性参数的方法 - Google Patents

一种用于实时生成北斗星基增强系统完好性参数的方法 Download PDF

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CN111983641B
CN111983641B CN202010445178.2A CN202010445178A CN111983641B CN 111983641 B CN111983641 B CN 111983641B CN 202010445178 A CN202010445178 A CN 202010445178A CN 111983641 B CN111983641 B CN 111983641B
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邵搏
丁群
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耿永超
熊帅
吴显兵
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/03Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers
    • G01S19/08Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing integrity information, e.g. health of satellites or quality of ephemeris data
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    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/03Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers
    • G01S19/07Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections
    • G01S19/072Ionosphere corrections
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/03Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers
    • G01S19/10Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals
    • G01S19/11Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
    • G01S19/115Airborne or satellite based pseudolites or repeaters
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
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    • G01S19/23Testing, monitoring, correcting or calibrating of receiver elements

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Abstract

本发明提供了一种用于实时生成北斗星基增强系统完好性参数的方法,通过监测站观测到的某颗卫星的双频伪距观测量和载波相位观测量,实时计算该颗卫星的改正数、DFRE和降效协方差矩阵,在120秒更新时刻将直接将计算的改正数、DFRE和降效协方差矩阵输出;在其他时刻,基于之前输出的改正数和降效协方差矩阵,实时估计DFRE,并将DFRE信息输出。本发明具有较强的工程实用性,能够为BDSBAS建设提供理论依据和实施思路,在改正数和降效协方差矩阵更新周期内,基于历史改正数和降效协方差矩阵信息估计DFRE,保证了更新周期内DFRE与改正数信息的相关性,确保用户端的完好性性能。

Description

一种用于实时生成北斗星基增强系统完好性参数的方法
技术领域
本发明涉及卫星导航增强技术领域,是北斗星基增强系统(BeiDou SatelliteBased Augmentation System,BDSBAS)中一种生成服务完好性参数的方法。
背景技术
BDSBAS是我国按照国际标准自主建设的星基增强系统(Satellite BasedAugmentation System,SBAS),通过中国境内分布的监测站,实现对经过我国上空的全球导航卫星系统(Global Navigation Satellite System,GNSS)的完好性监测,其提供的DFMC星基增强服务将满足国际民航组织规定的一类精密进近指标要求,其系统架构如图1所示。
BDSBAS的DFMC星基增强服务最多可以同时增强92颗卫星,增强对象为全球定位系统(Global Positioning System,GPS)、伽利略系统(GALILEO)、北斗全球卫星导航系统(BeiDou navigation satellite System,BDS)和格洛纳斯系统(GLONASS)。通过地球同步静止卫星(Geosynchronous Earth Orbit,GEO)卫星的B2a信号向用户播发卫星钟差改正数和轨道改正数等差分参数,以及双频测距误差(Dual-Frequency Range Error,DFRE)和降效协方差矩阵等完好性参数,实现定位精度和完好性等服务性能的提升。由于在双频定位模式下,用户可自行消除电离层延迟的影响,DFMC星基增强服务不再播发与电离层有关的差分和完好性参数。
DFRE和降效协方差矩阵是DFMC星基增强服务的重要完好性参数,反映的是卫星轨道和钟差改正数的修正效果。用户利用DFRE和降效协方差矩阵进行保护级计算,并与当前航路阶段的告警门限进行比较,以判定系统服务是否可用。
目前,国外尚未有公开文献对DFRE和降效协方差矩阵的实时解算方法进行描述。国内针对DFMC星基增强服务的完好性参数进行了初步研究,仅在DFRE和降效协方差矩阵的更新时刻进行解算。由于DFRE和降效协方差矩阵的更新间隔分别为6秒和120秒,此方法将导致120秒更新周期内的协方差矩阵与DFRE不匹配,影响用户完好性性能。
因此,需要一种合理的能够实时生成DFMC星基增强服务完好性参数的方法,保证BDSBAS DFMC星基增强服务的完好性性能。
发明内容
为了克服现有技术的不足,本发明提供一种用于实时生成北斗星基增强系统完好性参数的方法,通过监测站观测到的某颗卫星的双频伪距观测量和载波相位观测量,实时计算该颗卫星的改正数、DFRE和降效协方差矩阵,在120秒更新时刻将直接将计算的改正数、DFRE和降效协方差矩阵输出;在其他时刻,基于之前输出的改正数和降效协方差矩阵,实时估计DFRE,并将DFRE信息输出。
本发明解决其技术问题所采用的技术方案的具体步骤为:
步骤一:伪距残差解算
BDSBAS监测站采集所监测到全球卫星导航系统(Global Navigation SatelliteSystem,GNSS)卫星的观测数据和GNSS导航电文,监测站i观测到卫星j的双频观测数据如下:
Figure GDA0002698263360000021
Figure GDA0002698263360000022
Figure GDA0002698263360000023
Figure GDA0002698263360000024
其中,
Figure GDA0002698263360000025
Figure GDA0002698263360000026
分别为L1和L5频点上的伪距观测量;
Figure GDA0002698263360000027
Figure GDA0002698263360000028
分别为L1和L5频点上的载波相位观测量;
Figure GDA0002698263360000029
为监测站i和卫星j间的几何距离;
Figure GDA00026982633600000210
为对流层延迟;bi为监测站接收机时钟与GNSS系统时之间的偏差;Bj为卫星时钟与GNSS系统时之间的偏差;
Figure GDA00026982633600000211
为电离层延迟,对伪距观测量的影响是滞后,对载波相位观测量的影响是超前;
Figure GDA00026982633600000212
f1=1575.42MHz为载波L1的频率,f5=1176.45MHz为载波L5的频率;
Figure GDA00026982633600000213
Figure GDA00026982633600000214
为伪距观测量上的观测噪声;N1和N5为整周模糊度,λ1=C/f1和λ5=C/f5分别为载波L1和L5的波长,C为光速;
Figure GDA00026982633600000215
Figure GDA00026982633600000216
为载波相位观测量上的观测噪声;
首先对载波观测量进行如下变化:
Figure GDA00026982633600000217
Figure GDA00026982633600000218
式(5)、(6)中
Figure GDA00026982633600000219
中分别为L1、L5频点载波消电离层组合观测;
Figure GDA00026982633600000220
由于
Figure GDA00026982633600000221
前后两个时刻的整周模糊度基本相同,用
Figure GDA00026982633600000222
来平滑伪距观测量中的噪声;
Figure GDA0002698263360000031
其中,Lk表示L1或L5频点,
Figure GDA0002698263360000032
为相应频点的伪距观测量,
Figure GDA0002698263360000033
为相应频点平滑后的伪距观测量,τ=100s为平滑时间;
利用L1和L5频点平滑后的伪距观测量消除电离层延迟,消除电离层延迟后的伪距观测量
Figure GDA0002698263360000034
为:
Figure GDA0002698263360000035
将星历距离
Figure GDA0002698263360000036
卫星时钟偏差
Figure GDA0002698263360000037
和对流层延迟估计
Figure GDA0002698263360000038
Figure GDA0002698263360000039
中消除,得到伪距残差
Figure GDA00026982633600000310
Figure GDA00026982633600000311
其中,
Figure GDA00026982633600000312
由卫星星历位置和监测站位置计算得到;
Figure GDA00026982633600000313
为卫星时钟偏差,利用GNSS导航电文得出;ΔRj=[Δxj Δyj Δzj]T为卫星j在地心地固坐标系下X、Y、Z方向上的星历误差,即卫星星历位置与真实位置之间的误差;
Figure GDA00026982633600000314
为监测站i到卫星j的单位方向矢量;
Figure GDA00026982633600000315
为卫星j星历位置,利用GNSS导航电文得出;[xi yi zi]T为监测站接收机天线相位中心位置,通过测绘标校得出;ΔBj为卫星j的时钟误差;
Figure GDA00026982633600000316
为残余误差,方差为
Figure GDA00026982633600000317
步骤二:改正数和轨道钟差协方差矩阵解算;
利用卡尔曼滤波法求解式(9)得到轨道改正数
Figure GDA00026982633600000318
钟差改正数
Figure GDA00026982633600000319
轨道改正数变化率
Figure GDA00026982633600000320
钟差改正数变化率
Figure GDA00026982633600000321
和轨道钟差协方差矩阵
Figure GDA00026982633600000322
Xk(t)=φ*X(t-1) (10)
Pk(t)=φ*P(t-1)*φT+Q (11)
Figure GDA00026982633600000325
X(t)=Xk(t)+gain*(Zj-Hj*Xk(t)) (13)
P(t)=(E-gain*Hj)*Pk(t) (14)
Figure GDA00026982633600000323
Figure GDA00026982633600000324
其中,
Figure GDA0002698263360000041
Figure GDA0002698263360000042
Q为对线元素为0.0001的8×8的对角线矩阵,E为8×8的单位矩阵,P(t)4×4为P(t)前四行前四列元素组成的矩阵,M为观测到卫星j的监测站数量。
步骤三:T0时刻DFRE和降效协方差矩阵解算;
DFRE是修正残差在用户端的综合反映,需要对星历和时钟改正数在服务区域内的最大修正残差形成包络;
在t=T0时刻,DFRE(σDFRE)的计算公式为:
Figure GDA0002698263360000043
其中,T0为改正数和降效协方差矩阵的更新时刻;
Figure GDA0002698263360000044
Figure GDA0002698263360000045
为T0时刻卫星j在最大投影方向上的单位方向矢量;
Figure GDA0002698263360000046
Figure GDA0002698263360000047
为卫星j到服务区域内用户user的单位方向矢量,
Figure GDA0002698263360000048
为卫星j到服务区域内用户user的距离,[xuser yuser zuser]T为用户user的位置;
根据双频测距误差索引(Dual-Frequency Range Error Index,DFREI)映射表,将
Figure GDA0002698263360000049
转换为
Figure GDA00026982633600000410
映射表如表1所示:
表1 DFREI映射表
Figure GDA00026982633600000411
Figure GDA0002698263360000051
降效协方差矩阵
Figure GDA0002698263360000052
的表达式如下:
Figure GDA0002698263360000053
其中,
Figure GDA0002698263360000054
Figure GDA0002698263360000055
在DFREI映射表中对应的DFRE值;
步骤四:T1时刻DFRE估计;
在t=T1时刻,T1-T0<120秒,DFRE(σDFRE)的计算公式为:
Figure GDA0002698263360000056
其中,
Figure GDA0002698263360000057
Figure GDA0002698263360000058
为T1时刻卫星j在最大投影方向上的单位方向矢量;
Figure GDA0002698263360000059
为卫星j到服务区域内用户user的单位方向矢量,
Figure GDA00026982633600000510
为卫星j到服务区域内用户user的距离。
T1时刻和T0时刻改正数的修正差值ΔX满足下式:
Figure GDA00026982633600000511
得到:
Figure GDA00026982633600000512
其中,
Figure GDA00026982633600000513
为T1时刻DFRE估计值。
本发明是有益效果在于:
1)提出了实时生成北斗星基增强系统完好性参数DFRE和降效协方差矩阵的方法,给出了明确的处理流程和实施步骤,具有较强的工程实用性,能够为BDSBAS建设提供理论依据和实施思路;
2)在改正数和降效协方差矩阵更新周期内,基于历史改正数和降效协方差矩阵信息估计DFRE,保证了更新周期内DFRE与改正数信息的相关性,确保用户端的完好性性能。
附图说明
图1为北斗星基增强系统架构
图2为北斗星基增强系统完好性参数实时生成流程图。
具体实施方式
下面结合附图和实施例对本发明进一步说明。
本发明是一种用于实时生成北斗星基增强系统完好性参数的方法,具体步骤如图2所示:
步骤一:伪距残差解算
BDSBAS监测站采集所监测到全球卫星导航系统(Global Navigation SatelliteSystem,GNSS)卫星的观测数据和GNSS导航电文,监测站i观测到卫星j的双频观测数据如下:
Figure GDA0002698263360000061
Figure GDA0002698263360000062
Figure GDA0002698263360000063
Figure GDA0002698263360000064
其中,
Figure GDA0002698263360000065
Figure GDA0002698263360000066
分别为L1和L5频点上的伪距观测量;
Figure GDA0002698263360000067
Figure GDA0002698263360000068
分别为L1和L5频点上的载波相位观测量;
Figure GDA0002698263360000069
为监测站i和卫星j间的几何距离;
Figure GDA00026982633600000610
为对流层延迟;bi为监测站接收机时钟与GNSS系统时之间的偏差;Bj为卫星时钟与GNSS系统时之间的偏差;
Figure GDA00026982633600000611
为电离层延迟,对伪距观测量的影响是滞后,对载波相位观测量的影响是超前;
Figure GDA00026982633600000612
f1=1575.42MHz为载波L1的频率,f5=1176.45MHz为载波L5的频率;
Figure GDA00026982633600000613
Figure GDA00026982633600000614
为伪距观测量上的观测噪声;N1和N5为整周模糊度,由接收机失锁造成;λ1=C/f1和λ5=C/f5分别为载波L1和L5的波长,光速C=299792458m/s;
Figure GDA00026982633600000615
Figure GDA00026982633600000616
为载波相位观测量上的观测噪声,该噪声远远小于伪距观测量上的观察噪声。不同时刻的数据会进行标识,未做说明的数据均为t时刻的数据。
首先对载波观测量进行如下变化:
Figure GDA0002698263360000071
Figure GDA0002698263360000072
式(5)、(6)中
Figure GDA0002698263360000073
中分别为L1、L5频点载波消电离层组合观测;
Figure GDA0002698263360000074
由于
Figure GDA0002698263360000075
前后两个时刻的整周模糊度基本相同,用
Figure GDA0002698263360000076
来平滑伪距观测量中的噪声;
Figure GDA0002698263360000077
其中,Lk表示L1或L5频点,
Figure GDA0002698263360000078
为相应频点的伪距观测量,
Figure GDA0002698263360000079
为相应频点平滑后的伪距观测量,τ=100s为平滑时间;
利用L1和L5频点平滑后的伪距观测量消除电离层延迟,消除电离层延迟后的伪距观测量
Figure GDA00026982633600000710
为:
Figure GDA00026982633600000711
将星历距离
Figure GDA00026982633600000712
卫星时钟偏差
Figure GDA00026982633600000713
和对流层延迟估计
Figure GDA00026982633600000714
Figure GDA00026982633600000715
中消除,得到伪距残差
Figure GDA00026982633600000716
Figure GDA00026982633600000717
其中,
Figure GDA00026982633600000718
由卫星星历位置和监测站位置计算得到;
Figure GDA00026982633600000719
为卫星时钟偏差,利用GNSS导航电文得出;ΔRj=[Δxj Δyj Δzj]T为卫星j在地心地固坐标系下X、Y、Z方向上的星历误差,即卫星星历位置与真实位置之间的误差;
Figure GDA00026982633600000720
为监测站i到卫星j的单位方向矢量;
Figure GDA00026982633600000721
为卫星j星历位置,利用GNSS导航电文得出;[xi yi zi]T为监测站接收机天线相位中心位置,通过测绘标校得出;ΔBj为卫星j的时钟误差(利用导航电文中的卫星时钟偏差修正后的残余误差);
Figure GDA00026982633600000722
为残余误差,方差为
Figure GDA00026982633600000723
步骤二:改正数和轨道钟差协方差矩阵解算;
利用卡尔曼滤波法求解式(9)得到轨道改正数
Figure GDA00026982633600000724
钟差改正数
Figure GDA00026982633600000725
轨道改正数变化率
Figure GDA00026982633600000726
钟差改正数变化率
Figure GDA00026982633600000727
和轨道钟差协方差矩阵
Figure GDA00026982633600000728
Xk(t)=φ*X(t-1) (10)
Pk(t)=φ*P(t-1)*φT+Q (11)
Figure GDA00026982633600000810
X(t)=Xk(t)+gain*(Zj-Hj*Xk(t)) (13)
P(t)=(E-gain*Hj)*Pk(t) (14)
Figure GDA0002698263360000081
Figure GDA0002698263360000082
其中,
Figure GDA0002698263360000083
Figure GDA0002698263360000084
Q为对线元素为0.0001的8×8的对角线矩阵,E为8×8的单位矩阵,P(t)4×4为P(t)前四行前四列元素组成的矩阵,M为观测到卫星j的监测站数量。
步骤三:T0时刻DFRE和降效协方差矩阵解算;
DFRE是修正残差在用户端的综合反映,需要对星历和时钟改正数在服务区域内的最大修正残差形成包络;
在t=T0时刻,DFRE(σDFRE)的计算公式为:
Figure GDA0002698263360000085
其中,T0为改正数和降效协方差矩阵的更新时刻;
Figure GDA0002698263360000086
Figure GDA0002698263360000087
为T0时刻卫星j在最大投影方向上的单位方向矢量;
Figure GDA0002698263360000088
Figure GDA0002698263360000089
为卫星j到服务区域内用户user的单位方向矢量,
Figure GDA0002698263360000091
为卫星j到服务区域内用户user的距离,[xuser yuser zuser]T为用户user的位置;
根据双频测距误差索引(Dual-Frequency Range Error Index,DFREI)映射表,将
Figure GDA0002698263360000092
转换为
Figure GDA0002698263360000093
映射表如表1所示,例,
Figure GDA0002698263360000094
对应
Figure GDA0002698263360000095
表1 DFREI映射表
DFREI DFRE(σ<sub>DFRE</sub>) DFREI DFRE(σ<sub>DFRE</sub>)
0 0.125 8 1.5
1 0.25 9 1.75
2 0.375 10 2
3 0.5 11 2.5
4 0.625 12 3
5 0.75 13 4
6 1 14 10
7 1.25
降效协方差矩阵
Figure GDA0002698263360000096
的表达式如下:
Figure GDA0002698263360000097
其中,
Figure GDA0002698263360000098
Figure GDA0002698263360000099
在DFREI映射表中对应的DFRE值(例,
Figure GDA00026982633600000910
对应
Figure GDA00026982633600000911
)。
步骤四:T1时刻DFRE估计;
在t=T1时刻(T1-T0<120秒),DFRE(σDFRE)的计算公式为:
Figure GDA00026982633600000912
其中,
Figure GDA00026982633600000913
Figure GDA00026982633600000914
为T1时刻卫星j在最大投影方向上的单位方向矢量;
Figure GDA00026982633600000915
为卫星j到服务区域内用户user的单位方向矢量,
Figure GDA00026982633600000916
为卫星j到服务区域内用户user的距离。
T1时刻和T0时刻改正数的修正差值ΔX满足下式:
Figure GDA00026982633600000917
得到:
Figure GDA0002698263360000102
其中,
Figure GDA0002698263360000103
为T1时刻DFRE估计值。
本发明提出了一种用于实时生成北斗星基增强系统完好性参数的方法,解决了于当前双频完好性参数生成方法欠缺的难题。专业用户可通过上述步骤实时生成双频完好性参数,为高生命安全用户提供高可靠性的完好性内容服务,对我国北斗星基增强系统建设、DFMC星基增强服务加速形成具有重大的推进作用。

Claims (1)

1.一种用于实时生成北斗星基增强系统完好性参数的方法,其特征在于包括下述步骤:
步骤一:伪距残差解算;
BDSBAS监测站采集所监测到全球卫星导航系统卫星的观测数据和GNSS导航电文,监测站i观测到卫星j的双频观测数据如下:
Figure FDA0003511472520000011
Figure FDA0003511472520000012
Figure FDA0003511472520000013
Figure FDA0003511472520000014
其中,
Figure FDA0003511472520000015
Figure FDA0003511472520000016
分别为L1和L5频点上的伪距观测量;
Figure FDA0003511472520000017
Figure FDA0003511472520000018
分别为L1和L5频点上的载波相位观测量;
Figure FDA0003511472520000019
为监测站i和卫星j间的几何距离;
Figure FDA00035114725200000110
为对流层延迟;bi为监测站接收机时钟与GNSS系统时之间的偏差;Bj为卫星时钟与GNSS系统时之间的偏差;
Figure FDA00035114725200000111
为电离层延迟,对伪距观测量的影响是滞后,对载波相位观测量的影响是超前;
Figure FDA00035114725200000112
f1=1575.42MHz为载波L1的频率,f5=1176.45MHz为载波L5的频率;
Figure FDA00035114725200000113
Figure FDA00035114725200000114
为伪距观测量上的观测噪声;N1和N5为整周模糊度,λ1=C/f1和λ5=C/f5分别为载波L1和L5的波长,C为光速;
Figure FDA00035114725200000115
Figure FDA00035114725200000116
为载波相位观测量上的观测噪声;
首先对载波观测量进行如下变化:
Figure FDA00035114725200000117
Figure FDA00035114725200000118
式(5)、(6)中
Figure FDA00035114725200000119
中分别为L1、L5频点载波消电离层组合观测;
Figure FDA00035114725200000120
由于
Figure FDA00035114725200000121
前后两个时刻的整周模糊度基本相同,用
Figure FDA00035114725200000122
来平滑伪距观测量中的噪声;
Figure FDA00035114725200000123
其中,Lk表示L1或L5频点,
Figure FDA00035114725200000124
为相应频点的伪距观测量,
Figure FDA00035114725200000125
为相应频点平滑后的伪距观测量,τ=100s为平滑时间;
利用L1和L5频点平滑后的伪距观测量消除电离层延迟,消除电离层延迟后的伪距观测量
Figure FDA00035114725200000126
为:
Figure FDA0003511472520000021
将星历距离
Figure FDA0003511472520000022
卫星时钟偏差
Figure FDA0003511472520000023
和对流层延迟估计
Figure FDA0003511472520000024
Figure FDA0003511472520000025
中消除,得到伪距残差
Figure FDA0003511472520000026
Figure FDA0003511472520000027
其中,
Figure FDA0003511472520000028
由卫星星历位置和监测站位置计算得到;
Figure FDA0003511472520000029
为卫星时钟偏差,利用GNSS导航电文得出;ΔRj=[Δxj Δyj Δzj]T为卫星j在地心地固坐标系下X、Y、Z方向上的星历误差,即卫星星历位置与真实位置之间的误差;
Figure FDA00035114725200000210
为监测站i到卫星j的单位方向矢量;
Figure FDA00035114725200000211
为卫星j星历位置,利用GNSS导航电文得出;[xi yi zi]T为监测站接收机天线相位中心位置,通过测绘标校得出;ΔBj为卫星j的时钟误差;
Figure FDA00035114725200000212
为残余误差,方差为
Figure FDA00035114725200000213
步骤二:改正数和轨道钟差协方差矩阵解算;
利用卡尔曼滤波法求解式(9)得到轨道改正数
Figure FDA00035114725200000214
钟差改正数
Figure FDA00035114725200000215
轨道改正数变化率
Figure FDA00035114725200000216
钟差改正数变化率
Figure FDA00035114725200000217
和轨道钟差协方差矩阵
Figure FDA00035114725200000218
Xk(t)=φ*X(t-1) (10)
Pk(t)=φ*P(t-1)*φT+Q (11)
Figure FDA00035114725200000219
X(t)=Xk(t)+gain*(Zj-Hj*Xk(t)) (13)
P(t)=(E-gain*Hj)*Pk(t) (14)
Figure FDA00035114725200000220
Figure FDA00035114725200000221
其中,
Figure FDA0003511472520000031
Figure FDA0003511472520000032
Q为对线元素为0.0001的8×8的对角线矩阵,E为8×8的单位矩阵,P(t)4×4为P(t)前四行前四列元素组成的矩阵,M为观测到卫星j的监测站数量;
步骤三:T0时刻DFRE和降效协方差矩阵解算;
DFRE是修正残差在用户端的综合反映,需要对星历和时钟改正数在服务区域内的最大修正残差形成包络;
在t=T0时刻,DFRE(σDFRE)的计算公式为:
Figure FDA0003511472520000033
其中,T0为改正数和降效协方差矩阵的更新时刻;
Figure FDA0003511472520000034
Figure FDA0003511472520000035
为T0时刻卫星j在最大投影方向上的单位方向矢量;
Figure FDA0003511472520000036
Figure FDA0003511472520000037
为卫星j到服务区域内用户user的单位方向矢量,
Figure FDA0003511472520000038
为卫星j到服务区域内用户user的距离,[xuser yuser zuser]T为用户user的位置;
根据双频测距误差索引映射表,将
Figure FDA0003511472520000039
转换为
Figure FDA00035114725200000310
映射表如表1所示:
表1 DFREI映射表
Figure FDA00035114725200000311
Figure FDA0003511472520000041
降效协方差矩阵
Figure FDA0003511472520000042
的表达式如下:
Figure FDA0003511472520000043
其中,
Figure FDA0003511472520000044
Figure FDA0003511472520000045
在DFREI映射表中对应的DFRE值;
步骤四:T1时刻DFRE估计;
在t=T1时刻,T1-T0<120秒,DFRE(σDFRE)的计算公式为:
Figure FDA0003511472520000046
其中,
Figure FDA0003511472520000047
Figure FDA0003511472520000048
为T1时刻卫星j在最大投影方向上的单位方向矢量;
Figure FDA0003511472520000049
为卫星j到服务区域内用户user的单位方向矢量,
Figure FDA00035114725200000410
为卫星j到服务区域内用户user的距离;
T1时刻和T0时刻改正数的修正差值ΔX满足下式:
Figure FDA00035114725200000411
得到:
Figure FDA00035114725200000412
其中,
Figure FDA00035114725200000413
为T1时刻DFRE估计值。
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2928741A1 (fr) * 2008-03-11 2009-09-18 Thales Sa Dispositif et procede de surveillance d'integrite en temps reel d'un systeme de navigation par satellite
CN105068088A (zh) * 2015-06-29 2015-11-18 北京航空航天大学 双频卫星导航星基增强系统可用性预测方法
CN110007326A (zh) * 2019-04-15 2019-07-12 中国电子科技集团公司第二十研究所 一种用于星基增强系统的双频测距误差参数生成方法
CN110376618A (zh) * 2019-08-30 2019-10-25 北京航天宏图信息技术股份有限公司 基于北斗三号卫星星基增强的定位方法、装置及终端

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106468774B (zh) * 2016-09-09 2019-04-09 北京航空航天大学 一种应用于星基增强系统的星历星钟改正参数及空间信号完好性参数方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2928741A1 (fr) * 2008-03-11 2009-09-18 Thales Sa Dispositif et procede de surveillance d'integrite en temps reel d'un systeme de navigation par satellite
CN105068088A (zh) * 2015-06-29 2015-11-18 北京航空航天大学 双频卫星导航星基增强系统可用性预测方法
CN110007326A (zh) * 2019-04-15 2019-07-12 中国电子科技集团公司第二十研究所 一种用于星基增强系统的双频测距误差参数生成方法
CN110376618A (zh) * 2019-08-30 2019-10-25 北京航天宏图信息技术股份有限公司 基于北斗三号卫星星基增强的定位方法、装置及终端

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Estimation method of SBAS dual-frequency range error integrity parameter;Bo Shao等;《Satellite Navigation》;20200331;全文 *
Up-to-date SBAS DFMC Service Volume Prototype (DSVP) to support DFMC performance characterization activities;D.Salos等;《2018 IEEE》;20181231;全文 *
卫星导航星基增强系统及信号体制的比较;周昀等;《空间电子技术》;20160531;全文 *

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