匹配数据的平滑滤波技术

讨论了匹配测量数据的平滑，滤波和外推问题，所谓匹配测量数据是指位置参数和速度参数呈求导的匹配关系，提出了利用数据的匹配特性这一先验信息来改善多项式最小二乘滤波器的设计，对测量数据中的位置和测速数据进行统一处理，在最小方差意义下给出了平滑滤波公式及其效率方差比，由于充分利用了先验信息，减少了待估计参数的个数，显著提高了参数的估计精度，仿真计算结果表明该方法能显著改善目标运动参数的估计精度。     

双星定位的数据融合方法

双星定位系统需借助于第三个定 参考量。该文将双星定位系统和多套现有的靶场跟踪设备联用,利用数据融合方法,获得定位参数和速度参数,同时给出双星定位系统和靶场跟踪设备的系统误差估计。理论分析和仿真计算表明,该文方法有较高的精度。     

基于电子数据存储技术的微机化遥测处理系统

通过对某一高码速率光纤遥测系统中数据格式、码速率、数据容量、数据存储宽度、数据存储速率等特点的研究，提出了一种基于大容量电子数据存储器的微机化遥测处理系统，对存储的大容量数据阵列中的帧码识别、分路控制方法进行了讨论，并对受干扰数据处理时帧同步码检测的检测门限和同步对策参数进行了分析，最后给出了整个微机化的大容量遥测数据处理系统的软硬件设计方法，通过在６．５ＭｂｐｓＰＣＭ系统下的运行实验表明，整个方     

基于遥测数据动态特征的卫星异常检测方法

基于遥测参数分析异常是保证卫星正常在轨运行的基础,通常采用阈值法判断遥测参数是否超差来判断卫星工作状态,由于其无法检测在阈值范围内变化的卫星遥测数据异常,因而会导致故障漏报.本文利用遥测参数动态变化特性,提出一种基于遥测数据变化规律检测异常的方法.利用周期图谱法求解遥测参数周期,根据遥测数据各周期之间参数值的相似性,按照遥测参数周期对数据进行采样,得到平稳差分序列,对其建立自回归移动平均混合模型,通过精确的预测结果与实测遥测数据比较来发现异常.利用该方法对实际在轨运行的某卫星2012年5月太阳能帆板转动异常故障进行验证,结果表明其能够有效避免故障漏报.      

基于高动态GPS接收机输出数据的卫星自主导航

为了减轻地面测控站的压力,研究了利用高动态GPS数据进行卫星自主导航的方法;给出了旋转地球坐标系下的报轨动力学模型,在N点位置误差最小二乘指标下,导出了一种计算卫星初始状态的迭代算法;用某型号接收机输出的位置数据,进行了报轨算法的检验,验证了方法的有效性。     

多目标遥测系统方案的研究

根据多目标遥测系统的要求,提出了码分多址体制的多目标遥测方案,详细论述了码分多址体制的多目标遥测系统的工作原理及关键技术,并给出系统框图.该系统的特点是抗干扰能力强,可与GPS技术相结合实现遥、外测合一.     

基于天基雷达的空间目标轨道预测

根据天基雷达获取的空间目标位置和速度参数, 研究了计算空间目标轨道根数的方法, 以实现对空间目标的初定轨. 分析了雷达坐标系下对目标的观测误差给协议天球坐标系下的目标参数估计带来的影响. 提出了空间二体相遇问题的一种解决方案. 利用已知的空间站轨道, 仿真分析了空间目标在一周之内和空间站的相遇情况, 同时给出了目标轨道预测的误差分析.      

PDSTT状态下用FFT实现速度跟踪及提取角误差信息

本文讨论利用FFT技术在脉冲多卜勒雷达单目标跟踪(PDSTT)状态下实现速度跟踪的同时提取角误差信息。文中首先给出了用FFT解决这个问题的两种数学上等价的方法。进而提出通过建立同数据相拟合的AR(自回归)模型,将数据延拓,以克服由于FFT分批处理频率同锥扫频率之间的相互作用而带来的困难。最后给出利用上述方法在FELIX C—256计算机上进行模拟实验的结果。     

基于集成学习的遥测数据互相关结构知识发现

针对传统遥测数据相关性分析方法仅能发现相关程度知识，无法提供相关结构丰富信息的问题，提出一种神经网络与极限梯度提升（XGBoost）集成的遥测数据互相关结构知识发现方法。在对遥测时间序列进行线性、单调性、序对一致性、散点图形状4个维度相关结构信息标注的基础上，将混合采样、代价矩阵、神经网络、XGBoost算法相结合，直接对遥测数据进行分类得到其相关结构类别或相关关系有无的知识。采用量子卫星任务数据进行实验的结果表明:较之于原始XGBoost模型、融合混合采样与代价矩阵的XGBoost模型，所提方法在受试者工作特征（ROC）曲线、F1-score等性能指标方面具有更高的分类精度，且对类别不平衡数据不敏感，是一种适用于遥测数据互相关结构知识发现的有效方法。      

距离相关系数融合GPR模型的卫星异常检测方法

卫星在轨运行期间，遥测数据表现形式通常为多维时间序列。高斯过程回归(GPR)模型可以为重要的遥测参数提供动态门限，及时发现隐藏在工程阈值内的故障征兆，但是高维卫星数据使得GPR模型具有局限性。因此，为获取与多个遥测参数相关的动态门限，在GPR模型的基础上，融合距离相关系数对预测变量进行选择，减少信息冗余和计算量，提高模型的可解释性，并估计模型的泛化误差以设置更合理的预测区间，提高模型的泛化能力，检测数据流的持续异常。对实际在轨卫星数据进行仿真实验，验证了距离相关系数融合GPR模型的卫星异常检测方法可以在卫星故障早期检测到数据异常，而且提高了模型的预测性能，降低了虚警率。      

整星稳态温度的热网络分析方法

本文结合我国第一颗通信卫星的温度场计算,论述了航天器热计算中的网络分析方法,给出了经过网络修正以后的250个节点的稳态计算结果,并与地面模拟试验的数据以及飞行遥测的数据作比较分析表明,计算偏差绝大部分在2～8℃范围内,此外,对今后的热设计工作提出了几点看法。     

Radioactive satellites: Intact reentry and breakup by debris impact

There is a substantial mass of radioactive material in nuclear reactors or radioisotope thermal generators (RTGs) in orbit about the earth. This paper examines the reentry of intact nuclear fuel cores and RTGs and the fragmentation and subsequent radioactive debris cloud deposition and evolution resulting from the impact of orbital debris upon an orbiting reactor, fuel core, or RTG. To assess the intact reentry, decay rates and a predicted decay date using historical and projected orbital decay data, are estimated. The current NASA debris environment model is utilized to estimate impact rates and debris cloud evolution of a fragmentation event. Results of these analyses are compared and concepts are tendered which would tend to minimize the radiological debris hazard to personnel and structures both on the earth's surface and in low earth orbit.     

Improving science return using orbit navigation analysis based on non-imaging science data and the GGS visualization tool

Planetary spacecraft orbital position and instrument pointing knowledge can be incomplete and/or inaccurate due to many operational factors. The degree of error has at times resulted in many hours of re-analysis by the science teams. NASA's Geometry and Graphics Software (GGS), an analysis tool being developed at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado at Boulder, provides the scientist with a standardized method to adjust the look direction knowledge based on the best fit to the science instrument data. The GGS tool locates the instrument boresight based on telemetered spacecraft knowledge and then adjusts that pointing knowledge based on the science analysis of the data obtained from the observation. This technique is similar to the C-Smithing technique (Wang, et al. 1988) which adjusts pointing knowledge based on body placement within an imaging instrument frame. The corrected geometry knowledge, in the SPICE kernel format, is then available for distribution to all mission science teams and for archiving. An example based on the Galileo Ultraviolet Spectrometer (UVS) data from the Earth 1 encounter will be presented.     

Canopy photosynthesis and transpiration in microgravity: gas exchange measurements aboard Mir.

The SVET Greenhouse on-board the Orbital Station Mir was used to measure canopy photosynthesis and transpiration rates for the first time in space. During the Greenhouse IIB experiment on Mir (June-January 1997), carbon and water vapor fluxes from two wheat (cv. Superdwarf) canopies were measured using the US developed Gas Exchange Measurement System (GEMS). Gas analyzers capable of resolving CO2 concentration differences of 5 micromoles mol-1 against a background of 0.9% CO2, are necessary to measure photosynthetic and respiratory rates on Mir. The ability of the GEMS gas analyzers to measure these CO2 concentration differences was determined during extensive ground calibrations. Similarly, the sensitivity of the analyzers to water vapor was sufficient to accurately measure canopy evapotranspiration. Evapotranspiration, which accounted for over 90% of the water added to the root zone, was estimated using gas exchange and used to estimate substrate moisture content. This paper presents canopy photosynthesis and transpiration data during the peak vegetative phase of development in microgravity.     

Observations of solar-flare ionization in the mesosphere using coherent-scatter radar

Observations of solar-flare ionization in the mesosphere can be made using coherent-scatter radar systems. The scattered power profiles they measure in the 60–90 km altitude region is a function of the ion concentration gradient and the intensity of turbulent mixing at each atltitude. By comparing the power profiles before, during and after a solar flare, it is possible to estimate the ion production rate during the flare as a function of altitude and time. This analysis is used to compare the ion production rates with generally accepted ion-chemical models. Comparisons are made with ion production rates estimated from the solar X-ray flux for the same flare made by geostationary satellites.     

Comparison of ANN and MLR models for estimating solar radiation in Turkey using NOAA/AVHRR data

In this paper, the estimation capacities of MLR and ANN are investigated to estimate monthly-average daily SR over Turkey. The satellite data are used for 73 different locations over Turkey. Land surface temperature, altitude, latitude, longitude and month are offered as the input variables for modeling ANN and MLR to get SR. Estimations of SR are evaluated with the meteorological values by using the statistical bases. The obtained results indicated that the ANN model could achieve a satisfactory performance when compared to the MLR model. Moreover, it is understood that more accurate results in estimation of SR are obtained in the use of satellite data, rather than the use of meteorological station data. Finally, the built ANN model is used to estimate the yearly average of daily SR over Turkey. As a result, satellite-based SR map for Turkey is generated.     

定位与测速数据融合估计弹道稳定性与精度分析

基于Kalman滤波思想，利用增加观测矩阵秩的方法，讨论了轨道重建时测速数据对系统稳定性的影响；以一个仿真计算结果，说明了测速数据对提高处理精度的作用。文中结论证明，增加测速数据是提高系统稳定性和数据处理精度的主要途径之一。     

Balloon-borne,high-altitude gravimetry

Gravity measurements from a high-altitude balloon can verify global and upward-continued gravity models. A gravimeter suspended beneath a balloon is in a dynamic, and largely unpredictable, environment sensing accelerations due to gravity and balloon motions. Independent measurements of balloon motions using inertial navigation data combined with ground tracking data will allow for separation of balloon-induced accelerations from gravitational accelerations. Analysis of these data must estimate: 1) vertical gravimeter accelerations due to motion and gravity, 2) horizontal velocity to estimate the Eötvös effect, and 3) gravimeter position for comparison with gravity models. The first engineering test flight occurred on 11 October 1983, during the seasonal wind reversal and was very successful. Flight duration was approximately seven hours, with two hours of data collected at each of 30 km and 26 km altitudes. The results include gravity estimates, design criteria for future flights and feasibility analysis for vertical gravity profiles during ascent and descent.     

星敏感器用仪器星等的确定

仪器星等对正确评估星敏感器的灵敏度、捕获概率以及建立导航星表都有重要的意义。理论推导了色指数与接受器和恒星辐射之间的关系,证明星敏感器仪器星等可以由波段星等线性拟合得出,在此基础上由蓝光和可见光波段星等拟合计算了星敏感器的仪器星等,并与实测计算数据做了对比,结果表明用色指数计算仪器星等是可行的。更进一步对误差产生的原因也作了分析探讨,结合最近天文学的研究成果,提出了改进方法,从而使获得的拟合仪器星等与通过13波段观星数据计算得出的仪器星等的标准差不超过0.1个星等,满足当前星敏感器的要求。