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1.
许华冠 《中国科学院上海天文台年刊》1996,(17):150-161
本讨论了GPS相对定位中基准站的作用。通过实测资料的解算表明，在区域网的GPS相对定位解算中，为了克服参数之间的强相关性，得到非奇异解，应该固定基准站的坐标或给于它强的先验限制。本也分析了基准站坐标偏差对基线的长度的影响。 相似文献
2.
朱元兰 《中国科学院上海天文台年刊》2008,(1)
该文利用中国SLR网的实测资料,以SHORDE软件独立解算卫星的轨道和地球定向参数(EOP),并与全球SLR网解算的结果进行了比较。结果表明:中国SLR网30天弧段观测拟合轨道的中误差优于2cm。与全球SLR网解算结果相比,定轨的位置精度可优于50cm;5天弧段测定EOP的精度,Xp、Yp可优于5mas,Dr优于0.2ms。 相似文献
3.
上海VLBI，SLR和GPS站站坐标的精密测定和精度估计 总被引：1，自引：0，他引：1
本文对作为全球地球参考系基准站的上海VLBI，SLR和GPS站的站坐标进行了仔细的分析研究，并重新精密测定了SLR，GPS站的站坐标，给出了较可靠的精度估计，澄清了IERS的综合解所给出的上海SLR站站坐标存在的问题。 相似文献
4.
利用上海天文台多星定轨的软件（COMPASS），对1998年1月-2001年12月期间的Lageos-1、Lageos-2卫星的激光测距资料重新归算了地球定向参数EOP（COMPASS），并将结果与同期的EOP（IERS）C04进行了比较，得到其外符精度为：极移Xp-O．32mas，Yp-0．34mas，日长变化Dr-0．025ms。 相似文献
5.
通过比较地球定向参数（EOP）序列和对应的地因参考架，得到了依巴谷输入星表（HIC）和临时星表H37与国际地球自转服务（IERS）基于甚长基线干涉测量（VLBI）建立的河外天球参考架（ICRF）之间的旋转参数。在J2000．0历元，HIC和H37至ICRF的旋转分别为[7．4±1．1mas，70．0±1．2mas，86．8±6.9mas]和[－27.4±1.0mas，10.4±1．0mas，70．3±4．6mas]。由于光学仪器位置坐标精度较低，第三个旋转角的可信度较差。 相似文献
6.
详细地叙述了国际空间大地测量技术服务组织ILRS(International Laser Ranging Service),IVS(International VLBI Service),IGS(International GNSS Service)和IDS(International DORIS Service)分别采用SLR(satellite laser ranging),VLBI(very long baseline interferometry),GPS(global positioning system)和DORIS(Doppler orbitography and radio-positioning intergrated by satellite)四种技术,并由多家分析中心的站坐标和地球定向参数的SINEX(solution in independent exchange format)周解(或24 h观测解)进行技术内综合解算的方法,包括技术内综合模型的建立、参考架基准约束问题和不同分析中心解的定权方法等主要内容,并对ILRS,IVS,IGS和IDS提供的技术内综合周(日)解的长期序列进行了站坐标和地球定向参数(earth orientation parameters,EOP)的精度评估,分析了地球参考架基准参数的长期特性。由地球参考架基准定义可知,SLR技术内SINEX综合解相对于ITRF2014的平移参数时间跨度最长,且没有明显的偏差或漂移;GPS技术的三个方向平移参数虽然弥散度最低,但是在X方向和Y方向存在长期的线性变化,在Z方向存在跳变;DORIS技术也有类似GPS技术的现象。这些结果说明ITRF2014选择SLR定义的地心作为参考架原点是有道理的。通过分析台站坐标精度可知,利用各种技术对核心站和非核心站进行区分非常重要,所分别得到的精度有明显的不同。由于GNSS(global navigation satellite system)台站多且分布广,因此地球定向参数的确定精度要高于其他三种技术。 相似文献
7.
利用Lageos1SLR资料解算1990—2001年的地球定向参数 总被引：1，自引：0，他引：1
利用12年的Lageos1卫星激光测距资料(1990—2001)解算得到了地球定向参数(EOP)，将该序列的结果与同期的EOP(IERS)CO4进行比较，其外符精度为：极移Xp—0．40mas，Yp—0．42mas，日长变化Dr—0．035ms。 相似文献
8.
9.
利用22个IGS（International GNSS Service）跟踪站（IGS05）的连续观测资料估算地球自转参数ERP（Earth rotation parameters）（地球自转参数在测绘和卫星导航中是一组关键的参数）,并与IGS地球定向参数EOP（Earth orientation parameters）（UTC 12：00：00）和IERS（International Earth Rotation Service）C04（UTC 00：00：00）同时刻的结果相比较。比较结果表明：与IGS EOP比较,极移在x方向差值的RMS为0.0214 mas,极移在y方向差值的RMS为0.0662 mas,UT1-UTC差值的RMS为0.0260 ms;与IERS C04比较,极移在x方向差值的RMS为0.0203 mas,极移在y方向差值的RMS为0.0354 mas,UT1-UTC差值的RMS为0.0016 ms。以上差别均在IERS C04精度范围之内,我们解算的地球自转参数结果是可信的。 相似文献
10.
上海天文台VLBI，SLR和GPS站的归心结果与分析 总被引：1，自引：0，他引：1
本文重新处理了最近几年来利用GPS技术测定上海天文台GPS站坐标的资料，给出了GPS站相对于VLBI，SLR站的基线矢量，并与利用常规方法归心的最新结果进行了比较和,是到了IGS‘92联测中上海天文台GPS技术解算的SH01站坐标，与VLBI技术解算的结果比较，两者相差小于2.6cm，同时得到GPS技术归心的符精度好于1cm。 相似文献
11.
B. D. Tapley B. E. Schutz R. J. Eanes 《Celestial Mechanics and Dynamical Astronomy》1985,37(3):247-261
Satellite laser ranging (SLR) provides an important capability for precise orbit determination and for geophysical parameter estimation to support a number of contemporary geodynamic and oceanographic investigations. The precision of the SLR measurement has improved from the early meter-level systems to the current capabilities of a few centimeters for the best systems. The accuracy of the orbits and geophysical parameter recovery have shown an associated improvement. Polar motion with accuracies of 2 mas, station coordinates better than 10 cm, and interstation baseline rates indicative of tectonic motion are determined routinely with the current set of global SLR data. This discussion reviews the SLR measurement, analysis approach, and some of the recent results derived from the current SLR data set. 相似文献
12.
利用 12年的Lageos 1卫星激光测距资料 (1990 - 2 0 0 1)解算得到了地球定向参数 (EOP) ,将该序列的结果与同期的EOP(IERS)C0 4进行比较 ,其外符精度为 :极移XP— 0 .4 0mas,YP— 0 .4 2mas ,日长变化Dr— 0 .0 35ms。 相似文献
13.
本文分析了ＩＧＳ＇９２联测期间七个ＧＰＳ数据处理中心提供的极坐标序列。通过谱分析、最小二乘拟合和Ｆ检验，表明在这些序列中存在一些共同的高频波动：在Ｘ方向上具有２７．０，１６．５，１３．４和１０．４天的周期，在Ｙ方向上的波动周期约为２０．５，１５．８和１０．０天。并且每个序列与ＥＯＰ（ＩＥＲＳ）９２Ｃ０４之间都存在一个系统差。计算与分析表明，这些系统偏离的主要原因是由于在用ＧＰＳ资料解算Ｘ、Ｙ时，不同分析中心采用了不同系统的台站坐标（或者说只有部分台站采用了固定的台站坐标），从而造成这些序列所在的参考架与ＩＴＲＦ９１之间存在一个平移和旋转。最后，计算了该期间的大气角动量激发函数，可部分地解释该期间的Ｘ、Ｙ高频波动的原因。 相似文献
14.
乌鲁木齐天文站南山GPS跟踪站的地心坐标精确测定 总被引：1，自引：0，他引：1
利用GAMIT软件 ,采用有基准算法对乌鲁木齐南山观测基地新建GPS跟踪站GUAO的观测资料进行了归算 ,结果表明该站观测资料的质量是可靠的 ,并首次获得了该站在ITRF2 0 0 0中毫米级精度的地心坐标 相似文献
15.
Accurate Analytical Calculation of Effects of Rorations of the Central Planet on a Staellite's Orbit
Sergey M. Kudryavtsev 《Celestial Mechanics and Dynamical Astronomy》1997,67(2):131-144
Satellite orbital perturbations due to many rotations of the planet-fixed reference frame are calculated by a general analytical
method. For the International Terrestrial Reference Frame (ITRF) the effects of the Earth irregular rotation, precession,
nutation, and polar motion are considered. Gravity coefficients of the Earth potential expansion are expressed in an inertial
Celestial Reference Frame (CRF) as functions of the set of standard constant coefficients derived in the ITRF and of the rotation
angles between the CRF and ITRF. The analytical motion theory uses time dependent gravity coefficients, and the Lagrange motion
equations are integrated in the CRF, as it is done by numerical methods. Comparison of the proposed analytical method with
a numerical one is presented. Motion of the ETALON-1 geodetic satellite perturbed by the geopotential (36*36) and by the full
effects of the Earth irregular rotation, precession, nutation and polar motion is predicted. The r.m.s. difference between
the satellite's coordinates calculated by both methods over a year interval is 2 cm.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
对北京天文台动态频谱仪1996～1999年观测到的68群Ⅲ型爆发作了统计分析,并对这些事件的频率漂移、持续时间、偏振和带宽的基本特性作了定性分析. 相似文献
17.
单站精密定位 (PrecisePointPositioning ,以下简称PPP)是在同时固定GPS精密星历和卫星钟的前提下 ,利用载波相位和伪距资料进行单台站的精密点定位 .采用该方法时不同台站之间不存在共同的待估参数 ,即各台站互不相关 ,这一特点大大降低了计算量 .采用美国喷气推进实验室JPL发展的数据处理软件GIPSY处理APSG联测资料 ,计算表明PPP的重复率相当于目前国内普遍采用的双差解算结果 .采用较好保持地面网构型的无基准算法 ,计算表明通过Helmert参考系转换后 ,PPP的解算结果与双差算法的外符精度大致相当 .解算表明 ,采用PPP处理 1 0 0个台站约需 3 .5小时 ,而处理同样的资料采用双差算法则需 1 8～2 0小时 .对于我国即将建成的大科学工程或地震监测的多达 2 0 0 0个接收机的GPS网而言 ,在保持精度前提下的节省计算资源和计算时间的PPP解算方案值得广泛的应用 相似文献
18.
Constructing and maintaining a stable terrestrial reference frame(TRF) is one of the key objectives of fundamental astronomy and geodesy. The datum realization for all the global TRF versions,such as ITRF2014 and its predecessor ITRF2008, assumes linear time evolution for transformation parameters and then imposes some conditions on these Helmert transformation parameters. In this paper,we investigate a new approach, which is based on weekly estimation of station positions and Helmert transformation parameters from a combination of the solutions of four space-geodetic techniques, i.e.,Satellite Laser Ranging(SLR), Very Long Baseline Interferometry(VLBI), Global Positioning System(GPS) and Doppler Orbitography and Radiopositioning Integrated by Satellite(DORIS). For this study,an interval of one week is chosen because the arc length of the SLR solutions is seven days. The major advantage of this weekly estimated reference frame is that both the non-linear station motions and the non-linear origin motion are implicitly taken into account. In order to study the non-linear behavior of station motions and physical parameters, ITRF2008 is used as a reference. As for datum definition of weekly reference frame, on one hand SLR is the unique technique to realize the origin and determine the scale together with VLBI, and on the other hand the orientation is realized via no net rotation with respect to ITRF2005 on a subset of core stations. Given the fact that without enough collocations an inter-technique combined TRF could not exist, the selection and relative weight of local ties surveyed at co-location sites are critical issues. To get stable results, we first assume that, if there were no events such as equipment changes between the measurement epoch of the local tie and that of the spacegeodetic solution, the relative position between the two co-located stations should be invariant and this local tie could be used for computing the inter-technique combined reference frame in those weeks during the stable period of this tie. The resulting time series of both station positions and transformation parameters are studied in detail and are compared with ITRF2008. The residual station positions in the weekly combined reference frame are usually in the range of two millimeters without any periodic characteristic, but the residual station positions, when subtracting the regularized station position in ITRF2008, may reach a magnitude of a few centimeters and seem to have a significant annual signal.The physical parameter series between the weekly reference frame and ITRF2008 also show the obvious existence of an annual signal and reach a magnitude of one centimeter for origin motion and two parts per billion(ppb) for scale. 相似文献
19.
Differential equations ruling the Earth’s polar motion are slightly asymmetric with respect to the pole coordinates. This is not only associated with the lack of axial symmetry around the Earth figure axis (triaxiality) but also with the longitude dependency of the pole tide (the main contribution). We propose a consistent handling of both asymmetric contributions, formulating a unique equation in the complex equatorial plane, of which we derive a general solution. Difference with respect to the usual symmetric solution is discussed and found significant in light of the present accuracy of the observed pole coordinates. For the same geophysical excitation, the prograde Chandler wobble is accompanied by a retrograde component up to 2 milliarcseconds (mas), transforming it in a slight elliptic motion. The asymmetric contribution is relatively larger in the geodetic excitation function, for Chandler wobble excitation mixes prograde and retrograde components of comparable level (1 mas). 相似文献