共查询到19条相似文献，搜索用时 468 毫秒
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针对低轨卫星搭载BDS/GPS接收机实现定轨将成为定轨领域热点的现状,该文讨论了基于星载BDS/GPS实时定轨和精密定轨需要考虑的数学模型,阐述了实时定轨和精密定轨的模型差异。基于自主研发程序,利用高动态信号仿真器仿真的星载BDS/GPS数据研究了基于星载BDS/GPS实时定轨和精密定轨的可行性及其能达到的精度。试验结果表明,星载BDS/GPS实时定轨位置精度为1.19m,速度精度为2.35mm/s。GPS信号发生中断时即仅采用BDS观测数据进行实时定轨时,三维位置误差达到3.73m;星载BDS/GPS精密定轨位置精度为2.30cm,仅采用BDS观测数据进行精密定轨时,三维位置误差可达到8.26cm。 相似文献
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采用HY2A卫星2013年2月的实测数据,研究了GPS、星载多谱勒无线电定轨定位系统(DORIS)及卫星激光测距(SLR)三种观测数据的单独和联合定轨问题。通过与法国CNES的精密轨道数据比较发现:分别采用GPS、DORIS和SLR数据进行单独定轨,GPS数据确定轨道的径向平均精度为1.3cm,三维位置约为6.2cm;DORIS定轨的径向平均精度为1.6cm,比GPS结果略差;SLR确定轨道的径向平均精度为2.3cm。用GPS、DORIS和SLR三种数据联合定轨,确定轨道的径向平均精度为1.2cm,三维位置约为6.5cm。与星载GPS定轨结果比较,三种观测数据的联合定轨在提高卫星轨道确定精度上不明显,但联合定轨有利于保持计算轨道精度相对稳定。用站星间高度角大于60°的SLR数据检验GPS/DORIS联合确定的轨道,两者在测距方向的均方差为2.5cm,可见基于HY2A的观测数据可以实现cm级的定轨需求。 相似文献
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《武汉大学学报(信息科学版)》2010,(6)
在动力学模型补偿算法的基础上,推导了星载GPS实时定轨的卡尔曼滤波模型。以此为理论基础,自主研制了星载GPS实时定轨软件SATODS。使用CHAMP卫星上的星载GPS实测伪距数据以及GPS卫星广播星历来模拟实时定轨数据处理,并将实时定轨结果与JPL精密轨道进行比较分析。结果表明,在滤波收敛后,实时定轨的轨道精度和速度精度的3dRMS分别可达到1.0m和1.2mm/s,受观测数据的GPS卫星数、PDOP值、粗差数据和数据中断等因素的影响较小。 相似文献
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利用星载GPS对低轨卫星进行精密定轨已逐步成为一种主要手段.在简要介绍几种定轨方法的基础上,从星载GPS数据预处理出发,提出了将加权平均用于星载GPS低轨卫星几何轨道的动力学平滑方法,并利用实测数据进行了验证.结果表明,该方法实现过程简单,且能有效提高定轨精度. 相似文献
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LEO星载GPS双向滤波定轨研究 总被引：1，自引：1，他引：0
介绍了目前常用的LEO(low Earth orbiter)星载GPS定轨方法,分析了LEO星载GPS双向滤波定轨方法与其他几种主要定轨方法的区别.从卫星运动方程和星载GPS非差定轨观测方程出发,给出了LEO星载GPS双向滤波定轨方法的原理,采用自行研制的定轨软件对两颗GRACE(gravity recovery and climate ex-periment)卫星进行了定轨试验,通过与JPL(Jet Propulsion Laboratory)轨道的对比及KBR(k-band rangingsystem)观测数据的外部检核发现:①双向滤波定轨技术不仅能显著提高单向滤波开始阶段的定轨精度,而且可以从整体上提高卫星的定轨精度;②LEO星载GPS双向滤波定轨方法切实可行,相应的星载GPS定轨软件对GRACE卫星定轨精度在径向、沿轨方向和法向优于5 cm. 相似文献
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采用星载GPS双频观测数据,低轨卫星定轨的精度可以达到厘米级。采用GRACE A卫星的星载GPS观测数据,分别基于单频数据(C/A和L1)的半合组合观测量和双频数据的消电离层组合观测量,采用动力学低轨卫星定轨方法,解算了7d的GRACE A卫星轨道,解算结果与德国地学中心发布的快速科学轨道进行对比分析,并通过卫星激光测距观测数据进行检核。结果表明,通过半合组合观测量定轨得到的结果,在径向R、切向T、法向N方向的均方根误差平均值分别为7.9cm、20.1cm和5.5cm,三维定轨精度平均为22.8cm,利用卫星激光测距数据进行检核,残差平均值为-1.8cm,均方根误差为8.6cm。证明了采用单频观测数据进行定轨的可行性,并且定轨精度可以达到一般低轨卫星定轨精度的要求。 相似文献
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《武汉大学学报(信息科学版)》2020,(1)
风云三号C(Fengyun 3C,FY3C)卫星于2013年发射,搭载了全球导航卫星掩星探测仪(GNSS occultation sounder,GNOS),是国际首台兼容GPS和北斗卫星导航系统(BeiDou navigation satellite system, BDS)的掩星探测仪,可同时提供GPS和BDS双频观测数据,为研究星载GPS/BDS组合定轨提供了机会。为了实现分米级精度的星载GPS/BDS组合实时定轨,首先推导了基于载波相位观测值的星载GPS/BDS实时定轨数学模型;然后重点分析了GPS与BDS广播星历误差的变化特性,对不同类型轨道的BDS广播星历误差在信号传播路径(location of signal,LOS)方向的投影进行统计,并以此为依据,建立载波相位观测值的伪模糊度待估参数及其随机模型,用来吸收LOS方向的广播星历误差,从而实现分米级精度的实时定轨。采用自主研制的实时定轨软件SATODS对FY3C卫星GPS/BDS实测数据模拟在轨实时处理,结果表明,在使用广播星历的条件下,基于星载GPS/BDS载波相位实时定轨,可以达到30 cm的位置精度以及0.3 mm/s的速度精度。加入BDS观测数据后,虽然BDS卫星的广播星历整体精度低于GPS,但是通过合理设置伪模糊度参数的随机模型,实时定轨结果相对于单GPS有了一定的提高,当FY3C卫星经过亚太地区上空时,实时定轨精度可提高10%以上。 相似文献
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针对在星载GPS卫星定轨中由于卫星动力学模型误差和不可避免的观测异常严重影响定轨精度的问题,通过采用适当的自适应控制因子和应用抗差估计原理,构造自适应抗差扩展卡尔曼滤波(RAEKF)来实现星载GPS卫星定轨。实测计算表明,自适应抗差扩展卡尔曼滤波对观测误差和状态扰动有一定的抵制能力,与一般扩展卡尔曼滤波相比提高了精度,证明其理论的可行性。 相似文献
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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
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Precision real-time navigation of LEO satellites using global positioning system measurements 总被引：4，自引：3，他引：1
Continued advancements in remote sensing technology along with a trend towards highly autonomous spacecraft provide a strong
motivation for accurate real-time navigation of satellites in low Earth orbit (LEO). Global Navigation Satellite System (GNSS)
sensors nowadays enable a continuous tracking and provide low-noise radiometric measurements onboard a user spacecraft. Following
the deactivation of Selective Availability a representative real-time positioning accuracy of 10 m is presently achieved by
spaceborne global positioning system (GPS) receivers on LEO satellites. This accuracy can notably be improved by use of dynamic
orbit determination techniques. Besides a filtering of measurement noise and other short-term errors, these techniques enable
the processing of ambiguous measurements such as carrier phase or code-carrier combinations. In this paper a reference algorithm
for real-time onboard orbit determination is described and tested with GPS measurements from various ongoing space missions
covering an altitude range of 400–800 km. A trade-off between modeling effort and achievable accuracy is performed, which
takes into account the limitations of available onboard processors and the restricted upload capabilities. Furthermore, the
benefits of different measurements types and the available real-time ephemeris products are assessed. Using GPS broadcast
ephemerides a real-time position accuracy of about 0.5 m (3D rms) is feasible with dual-frequency carrier phase measurements.
Slightly inferior results (0.6–1 m) are achieved with single-frequency code-carrier combinations or dual-frequency code. For
further performance improvements the use of more accurate real-time GPS ephemeris products is mandatory. By way of example,
it is shown that the TDRSS Augmentation Service for Satellites (TASS) offers the potential for 0.1–0.2 m real-time navigation
accuracies onboard LEO satellites. 相似文献
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High Precision Orbit Determination of CHAMP Satellite 总被引：2，自引：0，他引：2
ZHAO Qile LIU Jingnan GE Maorong 《地球空间信息科学学报》2006,9(3):180-186
IntroductionCHAMP satellite was launched on July 15 ,2000 to study the earth gravity field, magneticfield, and at mosphere/ionosphere . CHAMPmission is managed by GeoForshungsZentrum(GFZ) Potsdam withinternational partners .In-cluding accelerometer ,star … 相似文献
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CHAMP卫星cm级精密定轨 总被引：4，自引：0，他引：4
在卫星定位导航数据综合处理软件（PANDA软件）的基础上，解算了2002年年积日126～131d CHAMP卫星的精密轨道，并通过与GFZ精密轨道的比较、GPS观测值的验后残差和SLR观测值检验等3种方式进行了轨道精度的评估。结果显示，本文的轨道精度在径向为4～5cm，切向和法向为6～8cm。 相似文献
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This study analyzes the quality of onboard data of tracking signals from GPS satellites on the far side of the earth and determines the orbit of the geostationary satellite using code and carrier phase observations with 30-h and 3-day orbit arc length. According to the analysis results, the onboard receiver can track 6–8 GPS satellites, and the minimum and maximum carrier to noise spectral densities were 24 and 45 dB-Hz, respectively. For a GPS receiver on a high-altitude platform above the navigation constellations, the blocking of the earth and a weak signal strength usually cause a piece-wise GPS signal tracking and an increase in the number of ambiguity parameters. Individual GPS satellites may be continuously tracked for as little as several minutes and as long as 3 h. Moreover, considering the negative sign of elevation angles reflects the fact that GPS satellites are tracked below the receiver in the study. GPS satellites appear mainly in the elevation angle range of ??53° to ??83°, and dilution of precision values could reach ten or one hundred and more. Also, it is observed that when a signal suffers from atmospheric refraction, other GPS signals tracked simultaneously by the receiver experience strong systematic errors in the code observations. Based on single-frequency code and carrier phase measurements, the mean 3D root mean square (RMS) value of the overlap comparisons between 30-h orbit determination arcs is 2.14 m. However, we found that there were also some biases in the carrier phase residuals, which contributed to poor orbit accuracy. To eliminate the effects of the biases, we established a correction sequence for each GPS satellite. After corrections, the mean 3D RMS was reduced to 0.99 m, representing a 53% improvement. 相似文献
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精密轨道确定在深空探测中至关重要,而定轨数据中的白噪声会影响定轨性能。基于零相位分析,比较了FRR（forward-filter reverse-filter reverse-output）、RRF（reverse-filter reverse-filter forward-output）和Matlab中的filtfilt这3种滤波器的优劣,设计了一种零相位Kaiser窗低通滤波器。利用火星快车号（Mars Express,MEX）的仿真数据和实测数据验证了零相位Kaiser窗低通滤波器的性能,结果发现滤除白噪声后MEX数据的定轨精度有了显著改善。双程测速数据残差均方根（root mean square,RMS）减小为原来的1/3左右,达到了0.031 mm/s;轨道位置和速度与欧空局（European Space Agency,ESA）精密轨道的差异明显变小。该滤波算法作为定轨前的数据预处理可以提高定轨精度,从而为中国火星探测器的轨道数据处理提供一定的参考。 相似文献