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41.
主要讨论由2颗地球同步轨道卫星组成的卫星预警系统(简称双星预警系统)中弹道导弹参数的估计问题。阐述了主动段运动的建模问题和弹道数据处理方法,考虑到微分求速的重要性,采用了带光滑约束的样条拟合方法。结合预警系统对弹道导弹预警的具体情况,分别讨论了预警系统下的发射原点估计、射向估计、关机时刻估计、关机点弹道参数估计、落点估计等问题。还讨论了系统中存在的两个问题的分析与解决。模型及分析方法均经过理论和仿真的验证,可应用于双星预警系统下的实际预警的研究。 相似文献
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谐振式光纤陀螺作为高精度角速度传感器,以其集成化高、成本低以及抗干扰性强等独有优势,逐渐成为下一代光学陀螺研究发展的热点。通过对谐振式光纤陀螺工作原理的分析,建立了陀螺数字信号处理系统可视化模型,并对系统谐振曲线和同步解调曲线等开环输出以及锁频反馈下闭环输出进行了模拟仿真。利用仿真模型分析了正弦波调制下谐振谱分裂现象,并搭建实验装置对其进行了验证。结果表明,实验中正弦信号调制频率高于系统谐振输出半高全宽一半,即对应2 MHz时,谐振谱分裂会导致同步解调输出线性区域出现明显失真,严重恶化了标度因数线性度。因此,搭建的谐振式光纤陀螺仿真模型能够准确而有效地模拟系统的工作状态,在系统噪声抑制和精度提升方面具有指导性意义。 相似文献
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Hui Lei ZhiGang Li XuHai Yang WenJun Wu Xuan Cheng Ying Yang ChuGang Feng 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
A new strategy of precise orbit determination (POD) for GEO (Geostationary Earth Orbit) satellite using SATRE (SAtellite Time and Ranging Equipment) is presented. Two observation modes are proposed and different channels of the same instruments are used to construct different observation modes, one mode receiving time signals from their own station and the other mode receiving time signals from each other for two stations called pairs of combined observations. Using data from such a tracking network in China, the results for both modes are compared. The precise orbit determination for the Sino-1 satellite using the data from 6 June 2005 to 13 June 2005 has been carried out in this work. The RMS (Root-Mean-Square) of observing residuals for 3-day solutions with the former mode is better than 9.1 cm. The RMS of observing residuals for 3-day solutions with the latter mode is better than 4.8 cm, much better than the former mode. Orbital overlapping (3-day orbit solution with 1-day orbit overlap) tests show that the RMS of the orbit difference for the former mode is 0.16 m in the radial direction, 0.53 m in the along-track direction, 0.97 m in the cross-track direction and 1.12 m in the 3-dimension position and the RMS of the orbit difference for the latter mode is 0.36 m in the radial direction, 0.89 m in the along-track direction, 1.18 m in the cross-track direction and 1.52 m in the 3-dimension position, almost the same as the former mode. All the experiments indicate that a meter-level accuracy of orbit determination for geostationary satellite is achievable. 相似文献
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S.I. Oronsaye L.A. McKinnell J.B. Habarulema 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
A new version of global empirical model for the ionospheric propagation factor, M(3000)F2 prediction is presented. Artificial neural network (ANN) technique was employed by considering the relevant geophysical input parameters which are known to influence the M(3000)F2 parameter. This new version is an update to the previous neural network based M(3000)F2 global model developed by Oyeyemi et al. (2007), and aims to address the inadequacy of the International Reference Ionosphere (IRI) M(3000)F2 model (the International Radio Consultative Committee (CCIR) M(3000)F2 model). The M(3000)F2 has been found to be relatively inaccurate in representing the diurnal structure of the low latitude region and the equatorial ionosphere. In particular, the existing hmF2 IRI model is unable to reproduce the sharp post-sunset drop in M(3000)F2 values, which correspond to a sharp post-sunset peak in the peak height of the F2 layer, hmF2. Data from 80 ionospheric stations globally, including a good number of stations in the low latitude region were considered for this work. M(3000)F2 hourly values from 1987 to 2008, spanning all periods of low and high solar activity were used for model development and verification process. The ability of the new model to predict the M(3000)F2 parameter especially in the low latitude and equatorial regions, which is known to be problematic for the existing IRI model is demonstrated. 相似文献
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基于浮空器的新型应急通信监测系统 总被引:1,自引:0,他引:1
介绍了一种新型的机动式空中应急通信监测系统,该系统以机动式系留气球和小型遥控飞艇为空中平台,搭载各种通信、侦察、监测等电子设备,具有快速灵活、机动性强、费用低廉等特点,能够适应复杂环境,面对突发事件时可以快速布置到任何需要的地方。 相似文献
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