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本文依据契比雷夫逼近理论设计了适用于航空重力测量数据处理的ＦＩＲ低通滤波器和ＦＩＲ低通差分器，根据航空重力测量的特点设计了航空重力测量数据的数字滤波处理框图， 相似文献
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航空重力测量是在８０年代后期实现高精度动态差分ＧＰＳ（ＤＧＰＳ）定位的基础上取得突破性进展的一项机载动态测量技术，目前已达到１～３ｍＧａｌ的空间重力异常精度和５～２０ｋｍ的波长分辨率，本文评述了航空重力测量的基本原理和三种主要方法，介绍了大飞机，小飞机和直升机系统的配置，试验及其结果，目前的研究表明，以ＤＧＰＳ／ＩＮＳ辅助的航空重力测量技术将成为９０年代测绘地球重力场的重要手段之一。 相似文献
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差分动态ＧＰＳ（ＤＧＰＳ）定位系统的发展给航空重力测量的研究活动注入了新的活力。本文依据我国目前航空重力测量的总体技术指标，讨论了航空重力测量对ＧＰＳ数据的精度要求，并与目前ＧＰＳ所能达到的精度作了比较，结果表明：ＧＰＳ已能基本满足航空重力测量所需的精度要求，但为精确确定垂直扰动加速度必须结合应用高质量的数字滤波器。 相似文献
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本文首先给出了航空矢量重力测量的数学模型，并依此得出了扰动重力矢量的误差模型。重点研究了平台式和捷联式两种情况下姿态误差对扰动重力矢量的影响，并得到了一致的姿态指标。水平姿态误差应小于0．2″，垂直姿态误差应小于10″，对航空矢量重力测量的发展具有一定的指导意义。 相似文献
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亚洲航空重力测量现状 总被引：1，自引：0，他引：1
近十几年来，航空重力测量技术的研究和应用日趋活跃，已成为地球重力场研究中的热门领域之一。本文概述了亚洲的主要航空重力测量，包括台湾、日本、马来西亚和蒙古航空重力测量。文中最后介绍了我国自行研制的航空重力测量系统的概况。 相似文献
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航空重力测量数据含有许多噪声，需用高质量的数字滤波器加以平滑。有限冲激响应（ＦＩＲ）滤波器的优点是具有精确线性相位而且总是稳定的。本文利用契比雪夫逼近方法，设计了适用于航空重力测量的ＦＩＲ低通滤波器。为检测其性能，文中建立了一个模拟加速度模型。检测结果表明：滤波器性能可靠，适用于航空重力测量数据处理。 相似文献
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Flight test results from a strapdown airborne gravity system 总被引：3，自引：0，他引：3
In June 1995, a flight test was carried out over the Rocky Mountains to assess the accuracy of airborne gravity for geoid
determination. The gravity system consisted of a strapdown inertial navigation system (INS), two GPS receivers with zero baseline
on the airplane and multiple GPS master stations on the ground, and a data logging system. To the best of our knowledge, this
was the first time that a strapdown INS has been used for airborne gravimetry. The test was designed to assess repeatability
as well as accuracy of airborne gravimetry in a highly variable gravity field. An east-west profile of 250 km across the Rocky
Mountains was chosen and four flights over the same ground track were made. The flying altitude was about 5.5km, i.e., between
2.5 and 5.0km above ground, and the average flying speed was about 430km/h. This corresponds to a spatial resolution (half
wavelength of cutoff frequency) of 5.07.0km when using filter lengths between 90 and 120s. This resolution is sufficient for
geoid determination, but may not satisfy other applications of airborne gravimetry. The evaluation of the internal and external
accuracy is based on repeated flights and comparison with upward continued ground gravity using a detailed terrain model.
Gravity results from repeated flight lines show that the standard deviation between flights is about 2mGal for a single profile
and a filter length of 120s, and about 3mGal for a filter length of 90s. The standard deviation of the difference between
airborne gravity upward continued ground gravity is about 3mGal for both filter lengths. A critical discussion of these results
and how they relate to the different transfer functions applied, is given in the paper. Two different mathematical approaches
to airborne scalar gravimetry are applied and compared, namely strapdown inertial scalar gravimetry (SISG) and rotation invariant
scalar gravimetry (RISG). Results show a significantly better performance of the SISG approach for a strapdown INS of this
accuracy class. Because of major differences in the error model of the two approaches, the RISG method can be used as an effective
reliability check of the SISG method. A spectral analysis of the residual errors of the flight profiles indicates that a relative
geoid accuracy of 23cm over distances of 200km (0.1 ppm) can be achieved by this method. Since these results present a first
data analysis, it is expected that further improvements are possible as more refined modelling is applied.
Received: 19 August 1996 / Accepted: 12 May 1997 相似文献
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D. Sampietro M. Capponi A. H. Mansi A. Gatti P. Marchetti F. Sansò 《Journal of Geodesy》2017,91(5):535-545
Regional gravity field modelling by means of remove-compute-restore procedure is nowadays widely applied in different contexts: it is the most used technique for regional gravimetric geoid determination, and it is also used in exploration geophysics to predict grids of gravity anomalies (Bouguer, free-air, isostatic, etc.), which are useful to understand and map geological structures in a specific region. Considering this last application, due to the required accuracy and resolution, airborne gravity observations are usually adopted. However, due to the relatively high acquisition velocity, presence of atmospheric turbulence, aircraft vibration, instrumental drift, etc., airborne data are usually contaminated by a very high observation error. For this reason, a proper procedure to filter the raw observations in both the low and high frequencies should be applied to recover valuable information. In this work, a software to filter and grid raw airborne observations is presented: the proposed solution consists in a combination of an along-track Wiener filter and a classical Least Squares Collocation technique. Basically, the proposed procedure is an adaptation to airborne gravimetry of the Space-Wise approach, developed by Politecnico di Milano to process data coming from the ESA satellite mission GOCE. Among the main differences with respect to the satellite application of this approach, there is the fact that, while in processing GOCE data the stochastic characteristics of the observation error can be considered a-priori well known, in airborne gravimetry, due to the complex environment in which the observations are acquired, these characteristics are unknown and should be retrieved from the dataset itself. The presented solution is suited for airborne data analysis in order to be able to quickly filter and grid gravity observations in an easy way. Some innovative theoretical aspects focusing in particular on the theoretical covariance modelling are presented too. In the end, the goodness of the procedure is evaluated by means of a test on real data retrieving the gravitational signal with a predicted accuracy of about 0.4 mGal. 相似文献
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Downward continuation and geoid determination based on band-limited airborne gravity data 总被引：4，自引：3，他引：4
The downward continuation of the harmonic disturbing gravity potential, derived at flight level from discrete observations
of airborne gravity by the spherical Hotine integral, to the geoid is discussed. The initial-boundary-value approach, based
on both the direct and inverse solution to Dirichlet's problem of potential theory, is used. Evaluation of the discretized
Fredholm integral equation of the first kind and its inverse is numerically tested using synthetic airborne gravity data.
Characteristics of the synthetic gravity data correspond to typical airborne data used for geoid determination today and in
the foreseeable future: discrete gravity observations at a mean flight height of 2 to 6 km above mean sea level with minimum
spatial resolution of 2.5 arcmin and a noise level of 1.5 mGal. Numerical results for both approaches are presented and discussed.
The direct approach can successfully be used for the downward continuation of airborne potential without any numerical instabilities
associated with the inverse approach. In addition to these two-step approaches, a one-step procedure is also discussed. This
procedure is based on a direct relationship between gravity disturbances at flight level and the disturbing gravity potential
at sea level. This procedure provided the best results in terms of accuracy, stability and numerical efficiency. As a general
result, numerically stable downward continuation of airborne gravity data can be seen as another advantage of airborne gravimetry
in the field of geoid determination.
Received: 6 June 2001 / Accepted: 3 January 2002 相似文献
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总结分析评述了海军重力研究团队在海空重力测量及应用技术研究领域取得的一些有理论意义和实用价值的研究成果,主要涵盖需求论证与顶层设计、观测数据归算与精度评估、测量误差分析处理与分离补偿、地表观测重力向上延拓、航空观测重力向下延拓、海域重力数据模型构建、地球外部重力场逼近和大地水准面精化等8个研究方向,重点从各项关键技术的研究背景、研究思路、难点突破、成果应用前景等几个方面进行了分析和总结,回答了该研究领域涉及理论方法和工程应用的一系列科学问题,为该领域未来发展提供借鉴和参考。 相似文献
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利用泊松积分法和点质量法对澳大利亚West Arnhem Land区域的航空重力测量数据进行了精度评估,两种方法得到精度结果基本一致,评估结果表明GT-1A测量系统2′分辨率数据的测量精度优于3×10-5 m/s2,5′分辨率数据的测量精度优于2×10-5 m/s2。利用交叉点平差和泊松积分法、点质量法对渤海区域的航空重力测量进行了内部交叉点平差和外部精度评估,结果表明,内部评估精度与外部评估精度存在一定的差异,以外部评估为准则,CHAGS测量系统在渤海区域5′分辨率的航空重力数据精度优于3.5×10-5 m/s2。综合国内外试验情况分析得到,在近海区域,航空重力数据的分辨率和精度受测量仪器的性能而不同,整体上对于5′分辨率数据而言,可以达到或优于3×10-5 m/s2的精度。 相似文献
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根据航空重力测量的要求以及滤波器的性能特点, 选择设计了适用于航空重力测量中ＧＰＳ高精度确定垂直扰动加速度的ＦＩＲ 低通滤波器和ＦＩＲ 低通微分器。并通过模拟数据的检测, 证明所设计的滤波器质量令人满意。 相似文献