基于广播星历的GPS卫星坐标的多项式拟合算法

以实例分析为基础,主要讨论了利用切比雪夫多项式拟合GPS卫星轨道时多项式阶数、时段长度、拟合点间隔等因素的设置问题;并对使用多组轨道参数进行轨道拟合的情况进行了分析;最后讨论了轨道参数的使用范围和选择问题;得出了有用的结论。     

长期GPS精密星历分析与轨道参数的函数逼近

以力学模型为基础,只能分析GPS卫星在短时间内的变化规律,而利用IGS提供的精密星历可以分析卫星在长时间段内的变化规律。基于精密星历研究了计算GPS卫星轨道参数的方法,然后对轨道参数在长时间段内的变化情况进行了分析,给出了分析的主要结果,并提出用正弦函数对轨道参数进行逼近,以得到GPS轨道的解析模型。     

长期GPS精密星历分析与轨道参数的函数逼近

以力学模型为基础,只能分析GPS卫星在短时间内的变化规律,而利用IGS提供的精密星历可以分析卫星在长时间段内的变化规律。基于精密星历研究了计算GPS卫星轨道参数的方法,然后对轨道参数在长时间段内的变化情况进行了分析,给出了分析的主要结果,并提出用正弦函数对轨道参数进行逼近,以得到GPS轨道的解析模型。     

星载InSAR方位向逐行的顺轨有效基线计算方法

本文开展了星载干涉合成孔径雷达(Interferometric synthetic aperture radar, InSAR)顺轨有效基线计算方法的改进研究。首先利用多项式拟合卫星轨道方程，使用相干系数法计算待配准图像对的像元偏移量，通过建立顺轨有效基线与方位向行号的函数关系式获得逐行有效基线，解决了在整幅图像使用固定有效基线带来的误差问题。通过TanDEM-X/TerraSAR-X实测干涉数据对本文的改进方法进行了应用和检验，同时针对所使用干涉图像对的特殊线性关系建立了快捷实用的线性方程。通过在整幅图像上精细化使用顺轨有效基线会对诸如海流反演方面有效提高反演精度。     

我国成功发射第二颗海洋卫星“海洋一号B”

4月11日11时27分,我国自行研制的“海洋一号B”卫星在太原卫星发射中心发射升空,卫星准确进入了预定轨道。“海洋一号B”卫星是“海洋一号A”卫星的后续星,卫星轨道为太阳同步近圆轨道,卫星经在轨测试合格后,将交付国家卫星海洋应用中心使用。     

世界首颗静止轨道海洋水色卫星应用研究进展

海洋环境参数和赤潮、绿潮等海洋灾害在一天之内会有明显的变化,需要高频率的观测才能满足监测的需求,极轨水色卫星观测频率低,而静止轨道水色卫星在观测频率方面具有绝对优势。2010年韩国发射了世界上第一颗静止轨道海洋水色卫星GOCI(Geostationary Ocean Color Imager),使小时级时间分辨率的水色遥感成为现实,各国科学家围绕该数据迅速开展了大量研究工作。本文首先介绍了GOCI遥感器的主要参数信息及其数据处理软件,然后综述了GOCI自问世至2016年的主要研究进展,涉及卫星数据处理、产品质量评价、海洋环境探测、海洋灾害监测、海洋动力过程探测、大气探测等方面,以期对我国水色遥感特别是静止轨道水色遥感应用研究提供参考。     

极轨气象卫星轨道报的自动传输提取和管理

更新和定时提供准确的轨道参数是保障获高质量极轨卫星资料的关键环节，本文介绍了卫星轨道报内容及格式，同时介绍了卫星轨道报自动传输提取和管理，并给出了实际运行情况和效果。     

GRACE卫星时变重力场去相关滤波参数选取分析

直接采用GRACE时变重力场模型反演地球表层质量变化的结果会呈现严重的南北方向条带状误差。滑动窗口拟合多项式方法是一种有效的经验性去相关滤波方法,能有效削弱中高纬度地区条带状误差。球谐系数去相关滤波起算阶数、滑动窗口宽度以及拟合多项式阶数是影响去相关滤波方法效果的关键因素。采用GRACE RL05时变重力场模型数据对去相关滤波的参数选取进行了实验分析,得到了去相关滤波的经验参数,实验结果表明:GRACE时变重力场模型去相关滤波起算阶数应取15阶,滑动窗口宽度应取5或7个点,拟合多项式阶数应设为3阶或4阶。     

GEOSAT卫星遥感资料研究南海海面动力高度场和地转流场

利用GEOSAT卫星在1987年和1988年执行ERM任务的雷达高度计资料来分析获取南海海面动力高度偏差的季节分布.根据卫星轨道误差和海域的特点,提出了适用于内海及边缘海域的二维共线轨道校正法,由此方法而得出的南海海面动力高度偏差的季节分布表明,南海表层流场在夏季总的环流形势是反气旋式环流,而冬季是气旋式环流.分析的结果同海上常规调查资料的分析结果相比较表明,在海流季节变化信号较强的海区(如南海中部和北部海区),利用高度计资料能很好地反映该海区的海流季节变化特征.     

基于GPS数据的CHAMP卫星简化动力法轨道确定

利用CHAMP卫星星载GPS实测数据,通过非差简化动力学定轨的方法,计算了CHAMP卫星2008年3月3日～10日的轨道,并以GFZ的快速轨道作为参考标准,评价了本文简化动力法轨道精度.结果表明,CHAMP卫星非差简化动力学轨道1D位置精度可达到7cm,1D的速度精度可达到0.1mm/s.     

顾及系统误差的地球静止轨道卫星PDOP值加权几何法定轨

对顾及系统误差的地球静止轨道（GEO）卫星几何法定轨做了初步探讨,给出顾及系统误差的GEO卫星几何法定轨数学模型,推导了参数解算公式,提出PDOP值加权的几何法定轨方法,并讨论了权函数的选取。最后以卫星钟差为例进行模拟计算。结果表明：顾及系统误差的GEO卫星几何法定轨,可大大减弱系统误差对定轨结果的影响;基于PDOP值加权的几何法定轨,可进一步提高系统参数解算精度和定轨精度。     

星载海洋高度计应用对测轨精度的要求

本文通过动力海洋学的典型空间尺度与ＯＥＯ－３，ＳＥＡＳＡＴ，ＧＥＯＳＡＴ和ＴＯＰＥＸ／Ｐｏｓｅｉｄｏｎ等卫星高度计测量高度的精度作比较，将星戴高度计应用对测轨精度的要求作了总结．对大多数海洋学研究来说、应用卫星高度计数据要求测轨精度达到数十厘米     

改进单组CEI基线对卫星定轨精度的影响研究

短基线相位干涉测量是一种被动测角卫星定轨跟踪方法,测量精度高。利用该方法采用单组正交双基线对静地卫星的定轨精度进行了仿真计算,并分别采用物理延长东西基线和东西基线阵列两种方法来考察对卫星定轨精度的改进情况。仿真结果表明,物理延长东西基线可以显著提高定轨精度;若星下点与跟踪网相距较远,则东西向基线阵列可显著提高定轨精度,且该方法对我国北斗卫星群的整体定轨效果很好,能进行几十米级的定轨。     

The Effects of GPS Carrier Phase Ambiguity Resolution on Jason-1

We have used GPS carrier phase integer ambiguity resolution to investigate improvements in the orbit determination for the Jason-1 satellite altimeter mission. The technique has been implemented in the GIPSY orbit determination software developed by JPL. The radial accuracy of the Jason-1 orbits is already near 1 cm, and thus it is difficult to detect the improvements gained when the carrier phase ambiguities are resolved. Nevertheless, each of the metrics we use to evaluate the orbit accuracy (orbit overlaps, orbit comparisons, satellite laser ranging residuals, altimeter crossover residuals, orbit centering) show modest improvement when the ambiguities are resolved. We conservatively estimate the improvement in the radial orbit accuracy is at the 10–20% level.     

The 1-Centimeter Orbit: Jason-1 Precision Orbit Determination Using GPS,SLR, DORIS,and Altimeter Data Special Issue: Jason-1 Calibration/Validation

The Jason-1 radar altimeter satellite, launched on December 7, 2001 is the follow on to the highly successful TOPEX/Poseidon (T/P) mission and will continue the time series of centimeter level ocean topography measurements. Orbit error is a major component in the overall error budget of all altimeter satellite missions. Jason-1 is no exception and has set a 1-cm radial orbit accuracy goal, which represents a factor of two improvement over what is currently being achieved for T/P. The challenge to precision orbit determination (POD) is both achieving the 1-cm radial orbit accuracy and evaluating the performance of the 1-cm orbit. There is reason to hope such an improvement is possible. The early years of T/P showed that GPS tracking data collected by an on-board receiver holds great promise for precise orbit determination. In the years following the T/P launch there have been several enhancements to GPS, improving its POD capability. In addition, Jason-1 carries aboard an enhanced GPS receiver and significantly improved SLR and DORIS tracking systems along with the altimeter itself. In this article we demonstrate the 1-cm radial orbit accuracy goal has been achieved using GPS data alone in a reduced dynamic solution. It is also shown that adding SLR data to the GPS-based solutions improves the orbits even further. In order to assess the performance of these orbits it is necessary to process all of the available tracking data (GPS, SLR, DORIS, and altimeter crossover differences) as either dependent or independent of the orbit solutions. It was also necessary to compute orbit solutions using various combinations of the four available tracking data in order to independently assess the orbit performance. Towards this end, we have greatly improved orbits determined solely from SLR+DORIS data by applying the reduced dynamic solution strategy. In addition, we have computed reduced dynamic orbits based on SLR, DORIS, and crossover data that are a significant improvement over the SLR- and DORIS-based dynamic solutions. These solutions provide the best performing orbits for independent validation of the GPS-based reduced dynamic orbits. The application of the 1-cm orbit will significantly improve the resolution of the altimeter measurement, making possible further strides in radar altimeter remote sensing.     

The 1-Centimeter Orbit: Jason-1 Precision Orbit Determination Using GPS, SLR, DORIS, and Altimeter Data

The Jason-1 radar altimeter satellite, launched on December 7, 2001 is the follow on to the highly successful TOPEX/Poseidon (T/P) mission and will continue the time series of centimeter level ocean topography measurements. Orbit error is a major component in the overall error budget of all altimeter satellite missions. Jason-1 is no exception and has set a 1-cm radial orbit accuracy goal, which represents a factor of two improvement over what is currently being achieved for T/P. The challenge to precision orbit determination (POD) is both achieving the 1-cm radial orbit accuracy and evaluating the performance of the 1-cm orbit. There is reason to hope such an improvement is possible. The early years of T/P showed that GPS tracking data collected by an on-board receiver holds great promise for precise orbit determination. In the years following the T/P launch there have been several enhancements to GPS, improving its POD capability. In addition, Jason-1 carries aboard an enhanced GPS receiver and significantly improved SLR and DORIS tracking systems along with the altimeter itself. In this article we demonstrate the 1-cm radial orbit accuracy goal has been achieved using GPS data alone in a reduced dynamic solution. It is also shown that adding SLR data to the GPS-based solutions improves the orbits even further. In order to assess the performance of these orbits it is necessary to process all of the available tracking data (GPS, SLR, DORIS, and altimeter crossover differences) as either dependent or independent of the orbit solutions. It was also necessary to compute orbit solutions using various combinations of the four available tracking data in order to independently assess the orbit performance. Towards this end, we have greatly improved orbits determined solely from SLR+DORIS data by applying the reduced dynamic solution strategy. In addition, we have computed reduced dynamic orbits based on SLR, DORIS, and crossover data that are a significant improvement over the SLR- and DORIS-based dynamic solutions. These solutions provide the best performing orbits for independent validation of the GPS-based reduced dynamic orbits. The application of the 1-cm orbit will significantly improve the resolution of the altimeter measurement, making possible further strides in radar altimeter remote sensing.     

卫星测高技术应用研究回顾与展望

简要介绍了笔者所在单位近十年来密切跟踪世界发展动态,灵活运用高新技术,致力于卫星测高技术应用研究所取得的一些有理论意义和实用价值的成果,这些成果主要包括四个方面：卫星测高径向轨道误差时域和空域特征分析、卫星测高反演海洋重力场、卫星测高反演海底地形以及利用测高重力异常扩展超高阶地球位模型研究成果。最后对这一研究领域未来的发展方向作了展望。     

一类改进的对地静止卫星中间轨道

通过引入拉格朗日方程,重构了定点坐标系下的对地静止(GEO)卫星摄动运动方程。继而把地球引力位在GEO卫星的定点邻域内泰勒展开,并采用拉普拉斯变换,得到了一类改进的中间轨道。5天的外推结果表明,改进的中间轨道精度相对于同类型的中间轨道精度提高了4个量级,且形式简单,可以很好地用于GEO卫星的定轨协方差分析中。同时,也可为GEO卫星轨道设计、地面观测站配置等工作提供参考。