我国毫米级框架实现与维持发展现状和趋势

主要从技术实现和维持方面讨论了我国CGCS2000框架与当前ITRF框架的不同。随着空间技术的进步,特别是我国自主的北斗卫星第三代卫星将实现信号的全球覆盖,发展以北斗卫星为主的毫米级全球基准将是我国基准发展的未来目标。毫米级站点坐标涉及两个因素:一是地球质心变化反演;二是站点的非线性运动建模。本文就国际上采用的地心反演方法进行了讨论、分析、比较。非线性运动建模部分重点介绍了奇异谱非线性建模技术,此方法相比地球物理效应分析建模方法有很明显的优势,可为我国CGCS2000框架点非线性运动维持提供依据。

The Current Status and Tendency of China Millimeter Coordinate Frame Implementation and Maintenance

The paper discusses differences between China Geodetic Coordinate System 2000 (CGCS2000) and later updated ITRF versions,such as ITRF2014,in terms of technical implementation and maintenance.With progress of space geodetic technology,also the development of the BeiDou navigation satellite system,especially third generation of BDS with signal global coverage in the future,it is possible for us to establish a global millimeter-level reference frame based on space geodetic technology including BDS.The millimeter reference frame implementation concerns two factors:① The variation of geocenter motion estimation;② the site nonlinear motion modeling.In this paper,the geocentric inversion methods are discussed and compared among results derived from various technical methods.Our nonlinear site movement modeling focuses on singular spectrum analysis method,which is of apparent advantages over earth physical effect modeling.All presented in the paper expected to provide reference to our future CGCS2000 maintenance.