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1.
“萤火一号”火星探测计划进展和Mars-SST火星卫星重力测量计划研究 总被引：3，自引：0，他引：3
本文回顾了国际火星探测计划的历史进程和科学意义,介绍了中国"萤火一号"火星探测计划的基本参数、发射过程、科学目标、核心载荷和关键技术,并且提出了中国将来Mars-SST火星卫星重力测量计划的实施建议:①基于探测精度较高、技术需求较少、测定速度较快、定轨要求较低、可借鉴GRACE的成功经验等优点,采用SST-LL-Doppler-VLBI系统观测模式;②先期开展高精度激光干涉星间测距仪、非保守力补偿系统等关键载荷和地面Doppler-VLBI系统的研制;③卫星轨道高度和星间距离分别设计为50～100 km和100±50 km;④先期开展仿真模拟研究。 相似文献
2.
重力卫星主要有效载荷指标分析与确定 总被引：5，自引：1，他引：5
在介绍重力卫星发展计划的基础上 ,研究讨论了重力卫星上的主要有效载荷。从重力测量的基本原理出发 ,推导了卫星轨道高度、有效荷载的精度需求、所能恢复的重力场最大空间分辨率和相应重力场参数精度之间粗略的函数关系。最后利用推导的公式计算了CHAMP、GRACE、GOCE卫星上几种主要测量有效载荷的指标 ,并将推得的指标与CHAMP、GRACE、GOCE卫星设计的指标进行了比较 ,得出了两种指标在量级上一致的结论。 相似文献
3.
卫星重力测量是当前探测全球一致、高精度和高分辨率地球重力场的高效技术手段,主要包括高低卫星跟踪卫星测量（satellite-to-satellite tracking in high-low mode, SST-hl）、低低卫星跟踪卫星测量（satellite-to-satellite tracking in low-low mode, SST-ll）和卫星重力梯度测量（satellite gravity gradiometry,SGG）。系统总结了利用卫星重力测量技术（包括SST-hl、SST-ll和SGG及多模式组合）反演地球重力场的主要方法,评述了利用挑战性小卫星有效载荷（challenging mini-satellite payload, CHAMP）、重力恢复与气候实验（gravity recovery and climate experiment, GRACE）/ GRACE继任者（GRACE follow-on, GRACE -FO）和地球重力场和海洋环流探索器（gravity field and steady-state ocean circulation explorer, GOCE）卫星重力数据构建静态和时变重力场模型的最新进展,并对当前具有代表性的地球重力场模型精度进行了分析和评估,以期对未来的地球重力场研究及其地学应用提供参考。 相似文献
4.
利用卫星跟踪卫星和卫星重力梯度测量技术来测定全球重力场，是近几年重力场测量领域的一个发展重点。由这些卫星上的各种数据获得的地球重力场模型在精度和分辨率上都得到了很大程度上的提高。本文首先以CHAMP、GRACE、GOCE三颗卫星为例，介绍了当前卫星重力测量的主要方法、原则，对三颗卫星的特点进行了说明。同时对三颗卫星的组成部分、轨道参数、应用领域进行了介绍。对于由CHAMP、GRACE卫星数据生成的重力场模型，文中进行了分析、评价和比较。 相似文献
5.
在卫星重力场测量中,星星跟踪是获取中高阶重力场模型的有效方式,是GRACE Follow-on、GRACE II等下一代国际重力卫星所采用的测量方式.星星跟踪重力卫星任务设计需要考虑轨道高度、星间距离、定轨误差、星间距离变化率测量误差、非引力干扰确定误差、任务测量时间和数据采样间隔等任务参数,这些参数共同决定了重力场测量的时间分辨率、空间分辨率及其精度等重力场测量性能.如何分析这些系统参数对重力场测量性能的复杂物理机理,进而提出合理、优化的任务参数设计方法,是星星跟踪重力场测量系统设计中的重要问题.为此,本文建立了星星跟踪重力场测量性能的解析计算模型,并利用GRACE重力卫星测量参数验证了该解析模型,进而提出了重力卫星系统参数设计方法,为实现星星跟踪重力场测量性能最大化奠定了理论基础. 相似文献
6.
利用GRACE和SWARM重力卫星星载GPS观测数据,基于简化动力学方法进行精密定轨,通过相位观测值残差分析、重叠轨道对比和科学轨道对比进行轨道精度检核。GRACE和SWARM卫星相位观测值残差RMS值稳定在6 mm左右,重叠轨道对比差值RMS在径向、切向和法向均优于1.24 cm;通过与GFZ和ESA提供的GRACE卫星与SWARM卫星精密轨道对比,GRACE卫星简化动力学轨道在R,T,N方向的轨道精度分别达到1.3 cm、2.1 cm和1.3 cm;SWARM卫星简化动力学轨道在径向、切向和法向的轨道精度分别达到0.8 cm、1.3 cm和1.6 cm。实验表明,基于简化动力学方法,GRACE和SWARM卫星定轨精度均到达厘米级。 相似文献
7.
现代大地测量学的重要任务之一就是确定地球重力场模型和大地水准面,卫星重力计划就是基于这一任务的。本文简要介绍了重力卫星发展的现状及其局限性,在发射时间、轨道倾角和主要星载设备等方面比较了CHAMP,GRACE和GOCE三颗重力卫星,最后简述了它们在地质构造、海洋学以及资源勘探等方面的最新应用,显示了重力卫星在科研和生产中不可替代的重要作用。 相似文献
8.
重力卫星的星载GPS精密定轨 总被引：3，自引：1，他引：2
利用CHAMP和GRACE卫星的实测数据,研究了重力卫星的精密定轨问题,并针对几何法精密定轨方法给出了一种有效的星载数据编辑策略;在PANDA软件的基础上,处理了101 d的实测数据;通过与不同机构卫星轨道的比较、激光测距观测值检验以及重力场模型恢复等外部检核的方式,分析了卫星轨道的精度.结果显示,本文的简化动力学轨道的精度为2～3 cm;几何学轨道的定轨精度为3～4 cm,适用于重力场模型的解算. 相似文献
9.
K波段微波测距系统(KBR)是低-低卫星跟踪卫星模式(SST-LL)重力测量卫星最关键的测量设备,其性能直接影响反演的地球时变重力场模型。超稳定振荡器(USO)作为整个KBR系统的频率基准,其稳定度对KBR系统测距精度有着重要影响。本文根据双向测量载波相位对比原理构建KBR仿真系统,利用幂率法模拟不同频率稳定度下的USO噪声误差,馈入到KBR仿真系统中进行仿真。结果表明,利用该模型当USO频率稳定度的阿伦方差达到1×10-12/s时,可满足公布的GRACE卫星KBR系统10μm的测距误差要求。 相似文献
10.
青藏高原隆升是地球上新生代以来最壮观的地质事件之一,对东亚乃至全球大陆动力学研究具有举足轻重的作用,一直是国际地球科学研究的热点区域.随着近年来现代大地测量技术(如GPS、卫星测高、绝对重力、雷达干涉测量等)的蓬勃发展,特别是2002年GRACE重力卫星的成功发射,为研究全球物质分布和季节性变化提供了重要参考依据,同时也为研究青藏高原动力学提供了可靠的观测数据和便捷的观测手段.GRACE卫星发射至今已超过13年,随着资料的累积和数据处理方法的改进与成熟,用GRACE卫星资料研究长期性变化成为新的热点. 相似文献
11.
重力卫星和测高卫星五年来的进展 总被引：4，自引：4，他引：0
对近年升空的重力卫星CHAMP和GRACE及将于近期升空的GOCE卫星,以及测高卫星ENVISAT,Jason1,GFO,ICESat和CryoSat的技术特点进行了介绍和评估。 相似文献
12.
Since its launch in 2002, the Gravity Recovery and Climate Experiment (GRACE) mission has been providing measurements of the
time-varying Earth gravity field. The GRACE mission architecture includes two satellites in near-circular, near-polar orbits
separated in the along-track direction by approximately 220 km (e.g. collinear). A microwave ranging instrument measures changes
in the distance between the spacecraft, while accelerometers on each spacecraft are used to measure changes in distance due
to non-gravitational forces. The fact that the satellites are in near-polar orbits coupled with the fact that the inter-satellite
range measurements are directed in the along-track direction, contributes to longitudinal striping in the estimated gravity
fields. This paper examines four candidate mission architectures for a future gravity recovery satellite mission to assess
their potential in measuring the gravity field more accurately than GRACE. All satellites were assumed to have an improved
measurement system, with an inter-satellite laser ranging instrument and a drag-free system for removal of non-gravitational
accelerations. Four formations were studied: a two-satellite collinear pair similar to GRACE; a four-satellite architecture
with two collinear pairs; a two-satellite cartwheel formation; and a four-satellite cartwheel formation. A cartwheel formation
consists of satellites performing in-plane, relative elliptical motion about their geometric center, so that inter-satellite
measurements are, at times, directed radially (e.g. parallel to the direction towards the center of the Earth) rather than
along-track. Radial measurements, unlike along-track measurements, have equal sensitivity to mass distribution in all directions
along the Earth’s surface and can lead to higher spatial resolution in the derived gravity field. The ability of each architecture
to recover the gravity field was evaluated using numerical simulations performed with JPL’s GIPSY-OASIS software package.
Thirty days of data were used to estimate gravity fields complete to degree and order 60. Evaluations were done for 250 and
400 km nominal orbit altitudes. The sensitivity of the recovered gravity field to under-sampled effects was assessed using
simulated errors in atmospheric/ocean dealiasing (AOD) models. Results showed the gravity field errors associated with the
four-satellite cartwheel formation were approximately one order of magnitude lower than the collinear satellite pair when
only measurement system errors were included. When short-period AOD model errors were introduced, the gravity field errors
for each formation were approximately the same. The cartwheel formations eliminated most of the longitudinal striping seen
in the gravity field errors. A covariance analysis showed the error spectrum of the cartwheel formations to be lower and more
isotropic than that of the collinear formations. 相似文献
13.
针对GRACE Level2卫星时变重力数据后处理方法如何评价的问题,该文以中国数字地震观测网络获得的青藏高原地区地面重力变化图像为参考,基于平均结构相似性等图像相似度指标,研究了与该区域地面重力观测同期、不同后处理方法得到的GRACE卫星重力变化图像的可靠性。结果显示,GRACE卫星重力和地面重力观测结果具有一定的可比性,滑动窗口去相关滤波和高斯400 km滤波的组合方法可以获得最优的处理效果。本文的方法和结论对GRACE及GRACE Follow-On卫星重力数据应用中后处理方法和参数的选取有一定的借鉴意义。 相似文献
14.
15.
Zhigui Kang Byron Tapley Srinivas Bettadpur John Ries Peter Nagel Rick Pastor 《Journal of Geodesy》2006,80(6):322-331
The GRACE (gravity recovery and climate experiment) satellites, launched in March 2002, are each equipped with a BlackJack GPS onboard receiver for precise orbit determination and gravity field recovery. Since launch, there have been significant improvements in the background force models used for satellite orbit determination, most notably the model for the geopotential. This has resulted in significant improvements to orbit accuracy for very low altitude satellites. The purpose of this paper is to investigate how well the orbits of the GRACE satellites (about 470 km in altitude) can currently be determined using only GPS data and based on the current models and methods. The orbit accuracy is assessed using a number of tests, which include analysis of orbit fits, orbit overlaps, orbit connecting points, satellite Laser ranging residuals and K-band ranging (KBR) residuals. We show that 1-cm radial orbit accuracy for the GRACE satellites has probably been achieved. These precise GRACE orbits can be used for such purposes as improving gravity recovery from the GRACE KBR data and for atmospheric profiling, and they demonstrate the quality of the background force models being used. 相似文献
16.
LUO Jia LUO Zhicai ZOU Xiancai WANG Haihong 《地球空间信息科学学报》2006,9(4):265-268
IntroductionThe high-accauary and high-resolution Earth’sgravity field can be recovered with satellite-to-satellite tracking (SST) technique , the preciseintersatellite tracking technique . The SSTtech-nique has been studied since 1960’s . The modesof S… 相似文献
17.
Taking China as the region for test the potential of the new satellite gravity technique, satelliteto-satellite tracking for improving the accuracy of regional gravity field model is studied. With WDM94 as reference, the gravity anomaly residuals of three models, the latest two GRACE global gravity field model (EIGEN_GRACE02S, GGM02S) and EGM96, are computed and compared. The causes for the differences among the residuals of the three models are discussed. The comparison between the residuals shows that in the selected region, EIGEN_GRACE02S or GGM02S is better than EGM96 in lower degree part (less than 110 degree). Additionally, through the analysis of the model gravity anomaly residuals, it is found that some systematic errors with periodical properties exist in the higher degree part of EIGEN and GGM models, the results can also be taken as references in the validation of the SST gravity data. 相似文献
18.
Approximate decorrelation and non-isotropic smoothing of time-variable GRACE-type gravity field models 总被引：6，自引：1，他引：6
Jürgen Kusche 《Journal of Geodesy》2007,81(11):733-749
We discuss a new method for approximately decorrelating and non-isotropically filtering the monthly gravity fields provided
by the gravity recovery and climate experiment (GRACE) twin-satellite mission. The procedure is more efficient than conventional
Gaussian-type isotropic filters in reducing stripes and spurious patterns, while retaining the signal magnitudes. One of the
problems that users of GRACE level 2 monthly gravity field solutions fight is the effect of increasing noise in higher frequencies.
Simply truncating the spherical harmonic solution at low degrees causes the loss of a significant portion of signal, which
is not an option if one is interested in geophysical phenomena on a scale of few hundred to few thousand km. The common approach
is to filter the published solutions, that is to convolve them with an isotropic kernel that allows an interpretation as smoothed
averaging. The downside of this approach is an amplitude bias and the fact that it neither accounts for the variable data
density that increases towards the poles where the orbits converge nor for the anisotropic error correlation structure that
the solutions exhibit. Here a relatively simple regularization procedure will be outlined, which allows one to take the latter
two effects into account, on the basis of published level 2 products. This leads to a series of approximate decorrelation
transformations applied to the monthly solutions, which enable a successive smoothing to reduce the noise in the higher frequencies.
This smoothing effect may be used to generate solutions that behave, on average over all possible directions, very close to
Gaussian-type filtered ones. The localizing and smoothing properties of our non-isotropic kernels are compared with Gaussian
kernels in terms of the kernel variance and the resulting amplitude bias for a standard signal. Examples involving real GRACE
level 2 fields as well as geophysical models are used to demonstrate the techniques. With the new method, we find that the
characteristic striping pattern in the GRACE solutions are much more reduced than Gaussian-filtered solutions of comparable
signal amplitude and root mean square. 相似文献
19.
B. Tapley J. Ries S. Bettadpur D. Chambers M. Cheng F. Condi B. Gunter Z. Kang P. Nagel R. Pastor T. Pekker S. Poole F. Wang 《Journal of Geodesy》2005,79(8):467-478
A new generation of Earth gravity field models called GGM02 are derived using approximately 14 months of data spanning from
April 2002 to December 2003 from the Gravity Recovery And Climate Experiment (GRACE). Relative to the preceding generation,
GGM01, there have been improvements to the data products, the gravity estimation methods and the background models. Based
on the calibrated covariances, GGM02 (both the GRACE-only model GGM02S and the combination model GGM02C) represents an improvement
greater than a factor of two over the previous GGM01 models. Error estimates indicate a cumulative error less than 1 cm geoid
height to spherical harmonic degree 70, which can be said to have met the GRACE minimum mission goals.
Electronic Supplementary Material Supplementary material is available in the online version of this article at 相似文献