我国天文大地网与卫星多普勒网联合平差的初步方案
A primary program for the Combined Adjustment of Astro-geodetic and Doppler-satellite Nets in China
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摘要: 本文提出的联合平差方案的要点是,先将天文大地网和卫星多普勒网按原定方案分别单独平差,然后将天文大地网和多普勒网的公共点的单独平差成果进行联合平差。在联合平差时,将公共点上的大地经纬度作为随机参数(即信号),以在天文大地网平差得到的这些点的经纬度值及其方差,作为信号的先验期望和先验方差,而以多普勒网平差得到的这些点在美国的NWL-10D地心坐标系统的坐标值作为相关观测值,列出它们的包含信号和另外几个参数的观测方程式,然后按最小二乘配置法进行平差。Abstract: This paper deals with a program of combined adjustment.Its main point is as follows.At first,the astro-geodetic net and Doppler-satellite net are adjusted respectively according to its own original program;secondly,the separately adjusted results of common points between the astro-geodetic net and Doppler-satellite net are to be jointly adjusted again.In the combined adjustment,the geodetic longitudes and latitudes of common points are regarded as random parameters(these are signals),the values of longitude and latitude of these points and variances obtained by the astro-geodetic adjustment are regarded as priori expectations and priori variances of signals,and their coordinates in the American NWL-10D coordinate system obtained by the Doppler net adjustment are regarded as correlated values of observation.Then observation equations which contain signals and other some non-random parameters(e.g transformation parameters between two ellipsoids,etc) are given.Finally it is adjusted according to the least squares collocation.