轨道外推器辅助下的高轨GNSS抗差定位算法

高轨卫星定轨一般使用基于地基的无线电、激光测量等方式,该方式通常存在测量时效性差、测量站点全球布站困难等问题。随着航天任务的逐步增多,卫星自主定轨重要性正在逐渐凸显,若卫星使用全球卫星导航系统(GNSS)进行定轨,将为其在轨自主运行提供便利。然而,高轨卫星搭载的GNSS接收机需要接收来自地球对侧的导航卫星信号,导致用户接收的信号强度极低,可用卫星数量少,且几何构型较差。本文针对高轨GNSS用户接收信号易被污染,使观测量出现粗差,导致定位解算结果缺乏鲁棒性的问题,提出了一种轨道外推器辅助下的高轨GNSS抗差定位算法。该算法基于传统GNSS与轨道外推器(OP)组合定位算法,针对高轨用户观测量的粗差进行抗差设计,提出了基于轨道外推器的预测结果对抗差定位算法中残差矢量和残差进行标准化的方法。本文对上述算法进行了仿真验证,在未添加粗差、GNSS信号仅受热噪声影响的条件下,传统GNSS/OP联合定位算法和轨道外推器辅助下的高轨GNSS抗差定位算法的定位精度分别为42.91 m和42.14 m;对观测量添加300 m粗差时,传统GNSS/OP组合定位算法定位精度为69.55 m,而轨道外推器辅助下的高轨GNSS抗差定位算法定位精度则为41.92 m。仿真结果表明,在对观测量添加不同粗差的情况下,添加粗差越大,轨道外推器辅助下的高轨GNSS抗差定位算法剔除粗差的效果越强,当添加300 m粗差时,轨道外推器辅助下的高轨GNSS抗差定位算法得到的定位精度与未添加粗差时基本相同,带有粗差的观测量被剔除,定位精度相比于传统GNSS/OP算法提升明显。因此,当部分观测量出现粗差时,轨道外推器辅助下的高轨GNSS抗差定位算法能够剔除带有粗差的观测量,提升定位精度。

Comparison of Development of Housing Construction in Regions of Slovakia and Czech Republic

Cities and municipalities are involved in the economic development of the whole country. One of the priorities of mayors is the usefulness of spatial disproportions of area as well as the structure and development of housing construction. They are natural canters of public and commercial services. The aim of the article is to determine if the geographic location of the region influences the number of new apartments with planning permission and completed apartments with a completion approval by using the methods of mathematical statistics ＂Analysis of variance＂. Meaning of the geographical location of the region as a factor, which influences the construction of apartments as well as regional differences in selected Central European countries, is subject of the conclusions of the paper.