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高精度GPS基线向量网平差 总被引：9，自引：0，他引：9
系统地论述了利用基线向量作为虚拟观测量进行平差的基本原理，着重对双因子抗差估计、系统参数求解、方差分量估计等在GPS基线网平差中的应用进行了分析，最后简单介绍了基线向量网平差软件GPSADJ。 相似文献
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GPS卫星和接收机天线绝对PCO、PCV对高精度基线解算的影响分析 总被引：1，自引：0，他引：1
在高精度GPS卫星导航数据处理中,卫星和接收机天线的PCO和PCV作为重要的误差来源之一,必须予以改正。本文从高精度基线解算入手,分析了卫星和接收机天线PCO和PCV中各项对高精度基线解算结果的影响。试验结果表明,接收机天线PCO、PCV对长基线或超长基线在各分量方向或长度上的影响最大可达到101 mm。卫星天线PCO、PCV对长基线在各分量方向或长度上的影响在毫米水平,最大不超过4 mm;对超长基线在各分量方向或长度上的影响最大可达到40 mm。 相似文献
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在给出组合GPS/GLONASS单点定位原理后,提出了利用Helmert验后方差估计法对GPS/GLONASS观测值定权的方法,并结合应用实例,通过对比分析说明该方法的可行性,实践表明该方法定权比采用固定权或经验定权更具有合理性。 相似文献
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The efficacy of robust M-estimators is a well-known issue when dealing with observational blunders. When the number of observations
is considerably large—long time series for instance—one can take advantage of the asymptotic normality of the M-estimation
and compute reasonable estimates for the unknown parameters of interest. A few leading M-estimators have been employed to
identify the most likely functional model for GPS coordinate time series. This includes the simultaneous detection of periodic
patterns and offsets in the GPS time series. Estimates of white noise, flicker noise, and random walk noise components are
also achieved using the robust M-estimators of (co)variance components, developed in the framework of the least-squares variance
component estimation (LS-VCE) theory. The method allows one to compute confidence interval for the (co)variance components
in asymptotic sense. Simulated time series using white noise plus flicker noise show that the estimates of random walk noise
fluctuate more than those of flicker noise for different M-estimators. This is because random walk noise is not an appropriate
noise structure for the series. The same phenomenon is observed using the results of real GPS time series, which implies that
the combination of white plus flicker noise is well described for GPS time series. Some of the estimated noise components
of LS-VCE differ significantly from those of other M- estimators. This reveals that there are a large number of outliers in
the series. This conclusion is also affirmed by performing the statistical tests, which detect (large) parts of the outliers
but can also leave parts to be undetected. 相似文献
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蠕变状态下Kalman定位精度通常与观测值方差有极大关系,BDS(BeiDou Navigation Satellite System)/GPS组合观测值方差易受观测值权比精确度的影响。为了提高位移探测精度、缩短初始坐标收敛时间及降低监测成本,本文采用时钟同步双天线BDS/GPS接收机,在构建单频单差组合定位模型基础上,分别对GPS和BDS观测值等价权进行抗差处理,利用引入时间相关遗忘因子的Helmert方差估计,精确确定GPS与BDS观测值权比,最后通过实时更新观测值方差,实现扩展Kalman滤波的逐历元定位。试验结果表明,针对短基线(1km),BDS/GPS抗差精密定权Kalman方法可显著缩短初始坐标收敛时间,位移探测精度可达到亚毫米级,位移收敛速率与移动窗口参数基本成反比关系,适用于具有蠕变特征形变体的监测。 相似文献
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南极国际GPS联测的海潮位移改正 总被引：1，自引：0，他引：1
根据海洋负荷潮理论,利用CRS4.0全球海潮模型,计算了参加南极国际GPS联测的中国南极长城站和中山站的海潮位移改正,并将海潮位移改正应用到GPS数据处理当中。在GAMIT软件的解算过程中,分别按加入和不加入海潮位移改正,对GPS基线分量进行了计算和比较分析。结果表明,对于南极国际GPS联测,海潮位移改正对GPS基线分量具有不可忽略的影响,数据处理时需要重点考虑。 相似文献
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目前GPS基线解算通常采用简化的等权随机模型,在复杂观测环境下采用该模型将影响定位结果的精度和可靠性。本文结合方差-协方差分量估计理论,论述了利用最优不变二次无偏估计(BIQUE)方法建立GPS精密随机模型的迭代算法,并进行了相应的软件模块设计。算例分析结果表明,该算法用于GPS随机模型精化是可行的,与等权随机模型比较,所建立的GPS双差观测值方差-协方差阵更符合实际,能有效地提高整周模糊度的可靠性和定位精度。 相似文献
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GPS精密定位中的海潮位移改正 总被引：2，自引：0，他引：2
根据海洋负荷潮理论，利用NAO99b全球海潮模型，计算了中国部分IGS站的海潮位移改正，并将海潮位移改正应用到GPS数据处理当中。在GAMIT软件的解算过程中，分别按加入和不加入海潮位移改正，对GPS基线分量和测站坐标分别进行了计算和比较分析。结果表明，海潮位移改正无论是对GPS基线分量还是对测站坐标，都有一定的影响。 相似文献
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Assessing receiver noise using GPS short baseline time series 总被引：14，自引：2，他引：14
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论文介绍了GPS/GLONASS组合静态相位相对定位模型,将GLONASS双差观测方程的模糊度参数表示成参考卫星的单差模糊度和双差模糊度参数;用误差分析法证明了单差模糊度按实参数估计不影响基线解算精度,而GLONASS双差模糊度必须按整参数进行解算;用Helmert方差分量估计确定GPS和GLONASS观测值的合理权比。实际观测数据处理结果表明：GPS/GLONASS组合定位较单一系统解算的基线精度均有提高,尤其比GLONASS单系统的解算精度有显著提高,比GPS单系统的精度也有适当提高,其中单历元基线解算精度约提高了10%,当单一系统的可用卫星数少于4颗时,GPS/GLONASS组合定位更具有应用价值。 相似文献
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The Ionosphere-weighted GPS baseline precision in canonical form 总被引：2，自引：2，他引：0
P. J. G. Teunissen 《Journal of Geodesy》1998,72(2):107-111
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在推导短距离ＧＰＳ测相双差观测方程的近似表达式的基础上,分析了卫星几何状态与基线位置对短基线解精度的影响,结合北京地铁复八线ＧＰＳ控制网资料分析,提出了工程及城市控制网型设计原则。 相似文献
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Regularization of geopotential determination from satellite data by variance components 总被引：11，自引：18，他引：11
Different types of present or future satellite data have to be combined by applying appropriate weighting for the determination
of the gravity field of the Earth, for instance GPS observations for CHAMP with satellite to satellite tracking for the coming
mission GRACE as well as gradiometer measurements for GOCE. In addition, the estimate of the geopotential has to be smoothed
or regularized because of the inversion problem. It is proposed to solve these two tasks by Bayesian inference on variance
components. The estimates of the variance components are computed by a stochastic estimator of the traces of matrices connected
with the inverse of the matrix of normal equations, thus leading to a new method for determining variance components for large
linear systems. The posterior density function for the variance components, weighting factors and regularization parameters
are given in order to compute the confidence intervals for these quantities. Test computations with simulated gradiometer
observations for GOCE and satellite to satellite tracking for GRACE show the validity of the approach.
Received: 5 June 2001 / Accepted: 28 November 2001 相似文献
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This paper describes the ocean loading tides corrections of GPS stations in Antarctica, such as the Great Wall station and Zhongshan station. Based on the theory of ocean loading tides, the displacement corrections of ocean loading tides on GPS stations in Antarctica are calculated by using the CRS4.0 ocean loading tides model. These corrections are also applied to GPS data processing. The GPS data are analyzed by the GAMIT software with and without these corrections. We compared and analyzed the GPS baseline components to get the differences. The results show that the ocean tidal displacement corrections have obvious effects upon GPS baseline components. Therefore, we should not ignore the ocean loading tides corrections of GPS stations in Antarctica to obtain precise and reliable results. 相似文献
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通过指出测量天线高的两种不规范操作,剖析了GPS天线高的测量方法及误差特性。而后首先从原理上分析了受天线高影响下的GPS基线和独立环闭合差的精度,然后通过某案例对数据进行处理,将两种受天线高影响下的上述测量成果与正常情况下的成果作比较,对理论分析进行证实。结果表明由天线高产生的粗差对短基线的测量成果影响较大,对长基线也有一定的影响。进而得出结论,即对于基线较短的校园GPS控制网,必须要重视对天线高的正确测量方法。而对工程单位布设的基线较长的GPS控制网,要获取高精度的定位成果,也不能忽视天线高的测量工作。 相似文献