共查询到19条相似文献，搜索用时 968 毫秒
1.
GPS水准采用移去恢复技术拟合大地水准面方法的研究 总被引：1，自引：0，他引：1
精化大地水准面是现代重力场和大地测量学工作的重要任务之一。探讨了利用已知水准点上的高程异常拟合区域大地水准面模型时,首先移去EGM96模型计算得到的部分,然后基于移动曲面和多面函数方法分别对剩余高程异常进行拟合,在内插点上再利用EGM96模型把移去的部分恢复,得到该点的高程异常。通过对某局部地区水准点的计算表明,引入EGM96模型的拟合高程异常的精度有所改进,对于大范围地区,这种方法有望能更好地提高大地水准面的拟合精度。 相似文献
2.
本文利用全球重力位模型、胶州市地面重力观测数据、胶州市GPS水准数据和数字地面模型(DTM),采用组合法应用移去-恢复技术计算剩余大地水准面,并与地球位模型计算的高程异常进行拟合,得到该地区重力似大地水准面,再和布测、计算得到的GPS/水准所构成的几何大地水准面拟合,利用多项式拟合完成系统改正,获得最终的大地水准面结果及相关的精度信息。 相似文献
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基于EGM2008重力场模型和GPS水准数据,采用“移去－恢复”方法拟合不同地域、不同面积区域似大地水准面,对该方法能够达到的精度情况进行分析,得出在没有似大地水准面精化的区域,且保证高程异常控制点精度及合理分布的情况下,采用基于EGM2008重力场模型的“移去－恢复”的方法可以实现厘米级的GPS点正常高转换。 相似文献
4.
本文利用全球重力位模型、胶州市地面重力观测数据、胶州市GPS水准数据和数字地面模型(DTM),采用组合法应用移去-恢复技术计算剩余大地水准面,并与地球位模型计算的高程异常进行拟合,得到该地区重力似大地水准面,再和布测、计算得到的GPS/水准所构成的几何大地水准面拟合,利用多项式拟合完成系统改正,获得最终的大地水准面结果及相关的精度信息。 相似文献
5.
陆海交界区域厘米级精度似大地水准面的确定 总被引：1，自引：0，他引：1
为了得到我国某陆海交界区厘米级精度的区域（似）大地水准面,利用43个高精度GPS／水准点和1045个实测重力点数据对EGM96,WDM94和GFZ计算的局部重力（似）大地水准面进行了比较与评价。结果表明,在该测区用移去．恢复法确定重力（似）大地水准面时,EGM96应该是首选参考重力场模型。该测区处在陆海交界处,海域无GPS／水准数据。经比较发现,采用距离倒数加权平均法将该区重力似大地水准面拟合于GPS／水准数据比在大范围使用的多项式法效果更好。采用该方法计算的测区（似）大地水准面精度优于3cm。 相似文献
6.
地面点的正常高可以通过GPS技术结合高精度、高分辨率的似大地水准面模型获得,以代替劳动强度大效率低的传统水准(或高程)测量。影响精度的因素有两个:GPS点大地高的测量精度和该点内插高程异常的精度。本文主要针对深圳市1km格网似大地水准面数据,利用克里金法内插拟合高程异常值,用实例说明克里金法在深圳市似大地水准面的应用中可以满足大比例尺数字化测图的需要。 相似文献
7.
张秀锦 《测绘与空间地理信息》2019,42(2)
为了充分利用GPS观测数据中的高程信息,获得GPS观测点的正常高,本文利用EGM96全球重力场模型和某区域GPS/水准数据,采用移去-恢复技术以几何方法计算了该区域2.5'×2.5'分辨率似大地水准面模型,经过内、外精度的检验,似大地水准面模型的精度优于0.07 m。结合区域内某工程布设的E级GPS控制网数据进行正常高的计算,并和水准实测高程进行比较,结果表明几何法确定的小区域似大地水准面模型结合GPS观测信息可以代替低等级的水准测量,满足一般工程对高程测量的需求。 相似文献
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为了得到我国某陆海交界区厘米级精度的区域(似)大地水准面,利用43个高精度GPS/水准点和1 045个实测重力点数据对EGM96,WDM94和GFZ计算的局部重力(似)大地水准面进行了比较与评价。结果表明,在该测区用移去-恢复法确定重力(似)大地水准面时,EGM96应该是首选参考重力场模型。该测区处在陆海交界处,海域无GPS/水准数据。经比较发现,采用距离倒数加权平均法将该区重力似大地水准面拟合于GPS/水准数据比在大范围使用的多项式法效果更好。采用该方法计算的测区(似)大地水准面精度优于3cm。 相似文献
10.
EGM96,WDM94和GPM98CR高阶地球重力场模型表示深圳局部重力场的比较与评价 总被引：9，自引：0，他引：9
为计算深圳精密重力大地水准面，利用62个高精度GPS水准点和4871个实测重力点数据对EGM96，WDM94和GPM98CR全球重力场模型表示深圳局部重力场进行了比较与评价。结果表明，由上述3个重力场模型计算的大地水准面高和重力异常与实测值之间存在明显的系统偏差，当采用GPS水准数据尽可能消除系统偏差以后，大地水准面高的精度得到显著提高，若应用移去-恢复技术确定深圳高精度大地水准面，则WDM94应该是首选的参考重力场模型。 相似文献
11.
基于EGM96模型的神经网络BP算法在GPS高程转换中的应用 总被引：1，自引：1，他引：0
在一个测区内,从水准联测点上移走EGM96含有的高精度中长波部分后,把余下的高程异常通过BP神经网络进行模拟,最后再对数据进行恢复,使实验达到良好的结果. 相似文献
12.
A. M. C. Srivastava 《Journal of Geodesy》1984,58(4):510-517
The astrogeodetic—gravimetric method based on the principle of least—squares solution has been used to determine the geocentric
Indian geodetic datum making use of the available nongeocentric astrogeodetic data and the gravimetric geocentric geoidal
heights in the form of smoothened values. Everett's method of interpolation has been used to obtain the smoothened geoidal
heights at the astrogeodetic stations in India from the available generalized values at 1°×1° corners. The values of the geoidal
height and deflections of the vertical at the geodetic datum Kalianpur H.S. so obtained have the negligible difference from
the values computed earlier by the same method using directly computed gravimetric geoidal heights at the astrogeodetic stations,
indicating that the use of the interpolated values in the astrogeodetic—gravimetric method employed would be an economical
approach of absolute orientation of a nongeocentric system if the gravimetric geoidal heights are available at 1°×1° corners
in the area of interest. 相似文献
13.
Inverse Vening Meinesz formula and deflection-geoid formula: applications to the predictions of gravity and geoid over the South China Sea 总被引：12，自引：0，他引：12
C. Hwang 《Journal of Geodesy》1998,72(5):304-312
Using the spherical harmonic representations of the earth's disturbing potential and its functionals, we derive the inverse
Vening Meinesz formula, which converts deflection of the vertical to gravity anomaly using the gradient of the H function. The deflection-geoid formula is also derived that converts deflection to geoidal undulation using the gradient
of the C function. The two formulae are implemented by the 1D FFT and the 2D FFT methods. The innermost zone effect is derived. The
inverse Vening Meinesz formula is employed to compute gravity anomalies and geoidal undulations over the South China Sea using
deflections from Seasat, Geosat, ERS-1 and TOPEX//POSEIDON satellite altimetry. The 1D FFT yields the best result of 9.9-mgal
rms difference with the shipborne gravity anomalies. Using the simulated deflections from EGM96, the deflection-geoid formula
yields a 4-cm rms difference with the EGM96-generated geoid. The predicted gravity anomalies and geoidal undulations can be
used to study the tectonic structure and the ocean circulations of the South China Sea.
Received: 7 April 1997 / Accepted: 7 January 1998 相似文献
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基于卫星动力学理论,采用德国地球科学中心GFZ提供的CHAMP精密轨道数据和星载加速度计数据,反演了36阶地球重力场模型CDS01S。用不同模型之间的位系数差比较模型CDS01S、EIGEN3P、EIGEN1S及EGM96,表明CDS01S模型的位系数最接近于EIGEN3P;比较上述几种模型的位系数精度,表明CDS01S模型的位系数精度高于EGM96;用CDS01S和GGM01C的前30阶位系数分别计算全球2°×2°网格的大地水准面起伏,两者之间的标准偏差为4.7 cm。 相似文献
16.
The earth gravity field model CDS01S of degree and order 36 has been recovered from the post processed Science Orbits and on-board accelerometer data of GFZ's CHAMP satellite. The model resolves the geoid with an accuracy of better than 4 cm at a resolution of 700 km half-wavelength. By using the degree difference variances of geopotential coefficients to compare the model CDS01S with EIGEN3P, EIGEN1S and EGM96, the result indicates that the coefficients of CDS01S are most close to those of EIGEN3P. The result of the comparison between the accuracies of geopotential coefficients in the above models, indicates that the accuracy of coefficients in CDS01S is higher than that in EGM96. The geoid undulations of CDS01S and GGM01C up to 30 degrees are calculated and the standard deviation is 4. 7 cm between them. 相似文献
17.
ZHOU Xuhua WU Bin PENG Bibo XU Houze 《地球空间信息科学学报》2006,9(4):250-254
IntroductionSince the launch of man-made satellite early in1957 ,the research for satellite gravity has beentaken a wide attentioninfield of geodesy .Early ,the ground-based satellite tracking has providedan observational data set which has been used tode… 相似文献
18.
H. Nahavandchi 《Journal of Geodesy》2002,76(6-7):345-352
It is suggested that a spherical harmonic representation of the geoidal heights using global Earth gravity models (EGM) might
be accurate enough for many applications, although we know that some short-wavelength signals are missing in a potential coefficient
model. A `direct' method of geoidal height determination from a global Earth gravity model coefficient alone and an `indirect'
approach of geoidal height determination through height anomaly computed from a global gravity model are investigated. In
both methods, suitable correction terms are applied. The results of computations in two test areas show that the direct and
indirect approaches of geoid height determination yield good agreement with the classical gravimetric geoidal heights which
are determined from Stokes' formula. Surprisingly, the results of the indirect method of geoidal height determination yield
better agreement with the global positioning system (GPS)-levelling derived geoid heights, which are used to demonstrate such
improvements, than the results of gravimetric geoid heights at to the same GPS stations. It has been demonstrated that the
application of correction terms in both methods improves the agreement of geoidal heights at GPS-levelling stations. It is
also found that the correction terms in the direct method of geoidal height determination are mostly similar to the correction
terms used for the indirect determination of geoidal heights from height anomalies.
Received: 26 July 2001 / Accepted: 21 February 2002 相似文献
19.
利用不同重力场模型（EIGEN-6C4、EGM2008）和海面高模型（DNSC08、DTU10、DTU13）确定了全球平均海面重力位均值62 636 856.550 7 m2s-2,加入海面地形改正后得到全球大地水准面重力位均值62 636 858.179 0 m2s-2。联合EGM2008模型与全国均匀分布的649个GPS/水准数据,根据异常位法、正常高反算法以及高程异常差法,分别计算了我国1985高程基准与全球高程基准之间的垂直偏差,并对3种垂直偏差结果通过加权方法进行了改善。最后,利用两种方法对垂直偏差结果的合理性与正确性进行验证。结果表明我国高程基准面高于全球平均海面0.298 0 m,高于全球大地水准面0.464 2 m。 相似文献