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1.
At the Delft University of Technology (DUT), data of six stations participating in the first international GLONASS tracking campaign, IGEX-98, were analyzed with integrity monitoring software. The software was developed at the Department of Mathematical Geodesy and Positioning of DUT. The main function of the software is to detect slips and outliers in phase and code observations in real time. In addition, the software also allows the validation of the information contained in the broadcast navigation messages. The results of the IGEX-98 data analyses are presented in a three part series. In this third and final part of the series, GLONASS and GPS navigation message validation results will be discussed in detail. The first part was concerned with the availability of GLONASS observations (Jonkman & de Jong, 2000a), while in the second part, GLONASS slip and outlier statistics were considered (Jonkman & de Jong, 2000b). The discussion of the navigation message validation results concentrates on anomalies detected in the data of an IGEX-98 station in Switzerland. Data collected at this station from September 1998 to December 1999 was analyized. In all, 19 anomalies were detected by the integrity monitoring software, 8 in GLONASS messages and 11 in GPS messages. The cause of the anomalies was established by evaluating the original data files, studying official bulletins of the GLONASS and GPS ground segments, and in some cases tracing the anomaly through the complete IGEX-98 network. ? 2000 John Wiley & Sons, Inc.  相似文献   

2.
The International GLONASS Experiment 1998 (IGEX-98) was the first international tracking campaign of the Russian counterpart to the Global Positioning System (GPS), GLONASS. Started in October 1998, the campaign was originally scheduled to last for three months. However, the launch of additional GLONASS satellites and a widespread enthusiasm among the participants led to an indefinite continuation of the campaign on a “best effort” basis. At the Delft University of Technology, the data of six IGEX-98 stations have been analyzed in detail with integrity monitoring software, developed at the Department of Mathematical Geodesy and Positioning of the University. The software aims to detect outliers and slips in code and phase observations in real time. In addition, the software also allows the validation of the information contained in the broadcast navigation messages. The results of the IGEX-98 data analyses will be presented in a three-part series. In the second part, GLONASS outlier and slips statistics will be discussed, while in the third part the anomaly detection results of the GLONASS and GPS messages will be shown. In this first part of the series, however, the most basic of all statistics will be considered: a simple day-to-day count of the number of GLONASS and GPS observations. Although simple, this statistic yields a surprising amount of information both on the availability of the GLONASS satellites and on the peculiarities of some of the receiver makes participating in the IGEX-98 campaign. ? 2000 John Wiley & Sons, Inc.  相似文献   

3.
GLONASS is a Russian military navigation satellite system. Even if the constellation is far from being operational, a large community is potentially interested in using its signal in combination with GPS to improve availability, integrity, or precision. The goal of this article is to present the international GLONASS campaign, named IGEX-98, which is really the first attempt to obtain precise GLONASS orbits for geodetic applications. A world-wide network of GLONASS receivers has been deployed and is still operational. Several analysis centers process the GLONASS data on a regular basis in the same way it is done for GPS within the International GPS Service. ? 1999 John Wiley & Sons, Inc.  相似文献   

4.
 The first results of the International GLONASS Experiment 1998 (IGEX-98) campaign have provided significant material to illustrate the mutual benefits of the GLONASS system and the realization of the International Terrestrial Reference System (ITRS). A specific aspect, namely the relationship between the World Geodetic System 1984 (WGS 84) and the PZ-90 system using ITRS as a primary standard, is investigated. A review of current works is carried out. A transformation strategy is proposed for the three systems based on recent results from IGEX-98 and an independent set of transformation parameters derived by the Jet Propulsion Laboratory from ITRF97 and PZ-90 coordinates for 16 global stations. Received: 9 June 2000 / Accepted: 12 June 2001  相似文献   

5.
The potential 48-satellite constellation offered by the combination of observations from both the GPS and GLONASS positioning systems has created considerable interest among existing GPS users. In the published literature, a considerable amount of work has been devoted to the theoretical issue of algorithm design for combined GPS/GLONASS positioning solutions. Little work has been published, however, on the practical conversion of existing GPS software to include GLONASS observations. This paper considers the computation issues pertaining to the GLONASS broadcast ephemeris for inclusion of GLONASS observations into existing GPS software. The format of the GLONASS broadcast ephemeris is discussed and theory of satellite orbits and their stepwise numerical integration is reviewed. Finally, a strategy for GLONASS broadcast ephemeris computation is proposed to facilitate combination of GPS and GLONASS observations. ? 1998 John Wiley & Sons, Inc.  相似文献   

6.
Laser-based validation of GLONASS orbits by short-arc technique   总被引:1,自引:0,他引:1  
 The International GLONASS Experiment (IGEX-98) was carried out between 19 October 1998 and 19 April 1999. Among several objectives was the precise orbit determination of GPS and GLONASS satellites and its validation by laser ranging observations. Local laser-based orbit corrections (radial, tangential and normal components in a rotating orbital local reference frame) are computed using a geometrical short-arc technique. The order of magnitude of these corrections is at the level of few decimeters, depending on the considered components. The orbit corrections are analyzed as a function of several parameters (date, orbital plane, geographical area). The mean corrections are at the level of several centimeters. However, when averaging over the entire campaign and for all the satellites, no mean radial, tangential and normal orbit corrections are found. The origin of the observed corrections is considered (errors due to the geocentric gravitational constant, the non-gravitational forces, the thermal equilibrium of on-board equipment, the reference systems, the location and the signature of the retroreflector array, and the precision of the satellite laser ranges). Some features are also due to errors in the radio-tracking GLONASS orbits. Further investigations will be needed to better understand the origin of various biases. Received: 17 February 2000 / Accepted: 31 January 2001  相似文献   

7.
在对GPS/GLONASS组合定位的周跳探测和修复方法进行深入研究的基础上,论述了适合于两种数据联合解算的GPS/GLONASS模糊度迭代处理方法及相应的基于FARA方法的整周模糊度固定方法。在现有BERNESE Ver4.0GSP数据处理软件的基础上,增加及改进了其中的若干模块,从而研制出组合定位系统高精度数据处理软件,并进行了试验计算。结果表明,所开发的组合定位系统数据处理软件内、外符合精度均达到mm级,证明了这种高精度相对定位理论、方法、软件的正确性和可行性。  相似文献   

8.
Utilization of frequency-division multiple access (FDMA) leads to GLONASS pseudorange and carrier phase observations suffering from variable levels inter-frequency bias (IFB). The bias related with carrier phase can be absorbed by ambiguities. However, the unequal code inter-frequency bias (cIFB) will degrade the accuracy of pseudorange observations, which will affect positioning accuracy and convergence of precise point positioning (PPP) when including GLONASS satellites. Based on observations made on un-differenced (UD) ionospheric-free combinations, GLONASS cIFB parameters are estimated as a constant to achieve GLONASS cIFB real-time self-calibration on a single station. A total of 23 stations, with different manufacturing backgrounds, are used to analyze the characteristics of GLONASS cIFB and its relationship with variable receiver hardware. The results show that there is an obvious common trend in cIFBs estimated using broadcast ephemeris for all of the different manufacturers, and there are unequal GLONASS inter-satellite cIFB that match brand manufacture. In addition, a particularly good consistency is found between self-calibrated receiver-dependent GLONASS cIFB and the IFB products of the German Research Centre for Geosciences (GFZ). Via a comparative experiment, it is also found that the algorithm of cIFB real-time self-calibration not only corrects receiver-dependent cIFB, but can moreover eliminate satellite-dependent cIFB, providing more stable results and further improving global navigation satellite system (GNSS) point positioning accuracy. The root mean square (RMS) improvements of single GLONASS standard point positioning (SPP) reach up to 54.18 and 53.80% in horizontal and vertical direction, respectively. The study’s GLONASS cIFB self-estimation can realize good self-consistency between cIFB and stations, working to further promote convergence efficiency relative to GPS?+?GLONASS PPP. An average improvement percentage of 19.03% is observed, realizing a near-consistent accuracy with GPS?+?GLONASS fusion PPP.  相似文献   

9.
The revitalized Russian GLONASS system provides new potential for real-time retrieval of zenith tropospheric delays (ZTD) and precipitable water vapor (PWV) in order to support time-critical meteorological applications such as nowcasting or severe weather event monitoring. In this study, we develop a method of real-time ZTD/PWV retrieval based on GLONASS and/or GPS observations. The performance of ZTD and PWV derived from GLONASS data using real-time precise point positioning (PPP) technique is carefully investigated and evaluated. The potential of combining GLONASS and GPS data for ZTD/PWV retrieving is assessed as well. The GLONASS and GPS observations of about half a year for 80 globally distributed stations from the IGS (International GNSS Service) network are processed. The results show that the real-time GLONASS ZTD series agree quite well with the GPS ZTD series in general: the RMS of ZTD differences is about 8 mm (about 1.2 mm in PWV). Furthermore, for an inter-technique validation, the real-time ZTD estimated from GLONASS-only, GPS-only, and the GPS/GLONASS combined solutions are compared with those derived from very long baseline interferometry (VLBI) at colocated GNSS/VLBI stations. The comparison shows that GLONASS can contribute to real-time meteorological applications, with almost the same accuracy as GPS. More accurate and reliable water vapor values, about 1.5–2.3 mm in PWV, can be achieved when GLONASS observations are combined with the GPS ones in the real-time PPP data processing. The comparison with radiosonde data further confirms the performance of GLONASS-derived real-time PWV and the benefit of adding GLONASS to stand-alone GPS processing.  相似文献   

10.
分析了 目前广播星历精度评估中存在的问题,详细论述了广播星历精度评估过程中对精密星历进行天线相位中心改正的取值方法,提出了利用单颗星单日钟差均值作二次差对广播星历钟差的系统性偏差进行改正的方法.选取2019-09-01-2019-11-01 共计62天的多模 GNSS 实验(multi-GNSS experiment,...  相似文献   

11.
为了对多个全球导航卫星系统(global navigation satellite system, GNSS)当前的广播星历精度进行一个全面的分析,对比了2014—2018年共5 a的GNSS广播星历与精密星历,并对全球定位系统(global positioning system, GPS)、格洛纳斯卫星导航系统(global navigation satellite system, GLONASS)、伽利略卫星导航系统(Galileo satellite navigation system, Galileo)、北斗卫星导航系统(BeiDou navigation satellite system, BDS)、准天顶卫星系统(quasi-zenith satellite system, QZSS)等5个系统的广播星历长期精度变化进行了分析。结果表明:5 a中GPS的广播星历轨道及钟差精度最稳定;GLONASS的广播星历轨道精度稳定性较好,但其钟差精度存在较大的离散度;Galileo得益于具备全面运行能力(full operational capability, FOC)卫星的大量发射及运行,其广播星历轨道、钟差精度大幅度变好,切向轨道、法向轨道与钟差精度已赶超GPS;BDS的广播星历轨道精度离散度较大,钟差精度出现不稳定现象;QZSS的广播星历轨道与钟差精度的稳定性与离散度相对最差。以2018年1 a的广播星历与精密星历为例分析了各个系统当前的广播星历精度,结果表明,当前GPS、GLONASS、Galileo、BDS、QZSS的考虑轨道误差与钟差误差贡献的空间信号测距误差(signal-in-space ranging error,SISRE)分别为0.806 m、2.704 m、0.320 m、1.457 m、1.645 m,表明Galileo广播星历整体精度最高,GPS次之,其次分别是BDS、QZSS和GLONASS。只考虑轨道误差贡献的SISRE分别为0.167 m、0.541 m、0.229 m、0.804 m、0.675 m,表明GPS广播星历轨道精度最高,其次分别是Galileo、GLONASS、QZSS和BDS。GPS卫星广播星历中新型号卫星的钟差精度总体要优于旧型号卫星。  相似文献   

12.
由于卫星广播星历有能被用户实时观测到的特点,因此为导航和实时定位提供了方便。精密星历是高精度的事后星历,而广播星历是由全球定位系统的地面控制部分所确定和提供,并经过卫星向全球用户公开播发的一种预报星历。本文选取了GPS和GLONASS卫星系统,并对GPS和GLONASS广播星历与精密星历计算的卫星位置对比分析,最后得出广播星历的精度与卫星和原子钟的类型有关的结论。  相似文献   

13.
激光在天空对地观测中的应用   总被引:1,自引:0,他引:1  
刘基余 《测绘工程》2001,10(2):15-19
1960年7月世界上第一台激光器问世后,激光测距迅速兴起,不管是地面激光测距,还是激光测卫和激光测月,都为大地测量学的发展作出了重大贡献;特别是激光测卫测月成果,为我们深化对地球动态效应的认识,揭示地球的奥秘,提供了许多重要的科学数据,本文综析了值得注视的下列新近发展。.在IGEX-98国际大联测中,求定GLONASS卫星的激光轨道与微波轨道之差;.评定PRN05/06号GPS卫星星历的精度;.检核Topex/Poseidon海洋测高卫星用GPS定轨的测量误差,.用机载激光测深系统测量海水的浓度;.用EOS-ALT星载激光测距/测高系统测量地球动态参数。  相似文献   

14.
Homogeneous reprocessing of GPS,GLONASS and SLR observations   总被引:3,自引:2,他引:1  
The International GNSS Service (IGS) provides operational products for the GPS and GLONASS constellation. Homogeneously processed time series of parameters from the IGS are only available for GPS. Reprocessed GLONASS series are provided only by individual Analysis Centers (i. e. CODE and ESA), making it difficult to fully include the GLONASS system into a rigorous GNSS analysis. In view of the increasing number of active GLONASS satellites and a steadily growing number of GPS+GLONASS-tracking stations available over the past few years, Technische Universität Dresden, Technische Universität München, Universität Bern and Eidgenössische Technische Hochschule Zürich performed a combined reprocessing of GPS and GLONASS observations. Also, SLR observations to GPS and GLONASS are included in this reprocessing effort. Here, we show only SLR results from a GNSS orbit validation. In total, 18 years of data (1994–2011) have been processed from altogether 340 GNSS and 70 SLR stations. The use of GLONASS observations in addition to GPS has no impact on the estimated linear terrestrial reference frame parameters. However, daily station positions show an RMS reduction of 0.3 mm on average for the height component when additional GLONASS observations can be used for the time series determination. Analyzing satellite orbit overlaps, the rigorous combination of GPS and GLONASS neither improves nor degrades the GPS orbit precision. For GLONASS, however, the quality of the microwave-derived GLONASS orbits improves due to the combination. These findings are confirmed using independent SLR observations for a GNSS orbit validation. In comparison to previous studies, mean SLR biases for satellites GPS-35 and GPS-36 could be reduced in magnitude from \(-35\) and \(-38\)  mm to \(-12\) and \(-13\)  mm, respectively. Our results show that remaining SLR biases depend on the satellite type and the use of coated or uncoated retro-reflectors. For Earth rotation parameters, the increasing number of GLONASS satellites and tracking stations over the past few years leads to differences between GPS-only and GPS+GLONASS combined solutions which are most pronounced in the pole rate estimates with maximum 0.2 mas/day in magnitude. At the same time, the difference between GLONASS-only and combined solutions decreases. Derived GNSS orbits are used to estimate combined GPS+GLONASS satellite clocks, with first results presented in this paper. Phase observation residuals from a precise point positioning are at the level of 2 mm and particularly reveal poorly modeled yaw maneuver periods.  相似文献   

15.
GLONASS卫星位置计算与程序实现   总被引:4,自引:0,他引:4  
针对导航GPS/GLONASS导航数据处理的需要,分析了GLONASS广播星历、地固坐标系PZ-90下卫星加速度简略公式,推导了利用定步长四阶龙贝格-库塔对轨道进行积分的计算公式,提出一种新的不需要进行轨道拟合的编程实现方法,该方法具有结构简单、运算快的特点,最后根据实际计算结果对积分区间、积分步长与积分坐标精度之间的关系进行分析,给出了实际积分计算合适的步长.  相似文献   

16.
介绍了基于广播星历的GPS/GLONASS组合导航单点定位的数学模型,分析了组合导航的技术难点。在GPS伪距法单点定位的基础上进行组合导航定位,其中GLONASS卫星坐标运用四阶龙格—库塔(Runge-Kutta)数值积分方法求得,利用一种新的不需要进行轨道拟合的编程方法来进行计算。以IGS跟踪站提供的观测数据为例,分别采用GPS、GLO-NASS和GPS/GLONASS三种方式组合进行伪距法单点定位,同时比较分析了不同权重选择对组合定位精度的影响。  相似文献   

17.
Due to the different signal frequencies for the GLONASS satellites, the commonly-used double-differencing procedure for carrier phase data processing can not be implemented in its straightforward form, as in the case of GPS. In this paper a novel data processing strategy, involving a three-step procedure, for integrated GPS/GLONASS positioning is proposed. The first is pseudo-range-based positioning, that uses double-differenced (DD) GPS pseudo-range and single-differenced (SD) GLONASS pseudo-range measurements to derive the initial position and receiver clock bias. The second is forming DD measurements (expressed in cycles) in order to estimate the ambiguities, by using the receiver clock bias estimated in the above step. The third is to form DD measurements (expressed in metric units) with the unknown SD integer ambiguity for the GLONASS reference satellite as the only parameter (which is constant before a cycle slip occurs for this satellite). A real-time stochastic model estimated by residual series over previous epochs is proposed for integrated GPS/GLONASS carrier phase and pseudo-range data processing. Other associated issues, such as cycle slip detection, validation criteria and adaptive procedure(s) for ambiguity resolution, is also discussed. The performance of this data processing strategy will be demonstrated through case study examples of rapid static positioning and kinematic positioning. From four experiments carried out to date, the results indicate that rapid static positioning requires 1 minute of single frequency GPS/GLONASS data for 100% positioning success rate. The single epoch positioning solution for kinematic positioning can achieve 94.6% success rate over short baselines (<6 km).  相似文献   

18.
Modeling and assessment of combined GPS/GLONASS precise point positioning   总被引:4,自引:2,他引:2  
A combination of GPS and GLONASS observations can offer improved reliability, availability and accuracy for precise point positioning (PPP). We present and analyze a combined GPS/GLONASS PPP model, including both functional and stochastic components. Numerical comparison and analysis are conducted with respect to PPP based on only GPS or GLONASS observations to demonstrate the benefits of the combined GPS/GLONASS PPP. The observation residuals are analyzed for more appropriate stochastic modeling for observations from different navigation systems. An analysis is also made using different precise orbit and clock products. The performance of the combined GPS/GLONASS PPP is assessed using both static and kinematic data. The results indicate that the convergence time can be significantly reduced with the addition of GLONASS data. The positioning accuracy, however, is not significantly improved by adding GLONASS data if there is a sufficient number of GPS satellites with good geometry.  相似文献   

19.
Within the regional EUREF Permanent Network (EPN) all positioning is purely based on GPS. This paper investigates, using the Bernese GNSS analysis software, the influence of adding GLONASS observations to the EPN processing using fixed orbits from the International GNSS Service (IGS) as well as from the CODE analysis centre. The GPS-only coordinates and GPS + GLONASS coordinates will be compared and the change in their repeatabilities will be investigated. The influence of the used orbits will also be outlined. The results show that a combined GPS + GLONASS data analysis can be set up without major efforts and that it will not degrade the positions obtained within the EPN.  相似文献   

20.
1 IntroductionReal_timekinematicGPSprecisepositioninghasbeenplayinganincreasingroleinbothsurveyingandnavigation ,andhasbecomeanessentialtoolforpreciserelativepositioning .However,reliableandcorrectambiguityresolutiondependsonobserva tionsuponalargenumbe…  相似文献   

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