由空间距离和方位角进行大地主题解算

Solution to Geodetic Problem Through Space Distance and Azimuth

通常以椭球面作为计算基准面,而测量得到的直线距离不能直接用于椭球面计算。本文介绍了在已知方位角和空间距离情况下的大地主题解算问题。提出采用迭代的方法,首先将空间距离认为是大地线长度的初值,利用大地主题正算公式计算出端点坐标,根据求得端点坐标反算空间距离,将其与测得空间距离的差作为大地线长度的修正量,重新计算端点坐标,迭代至距离的反算值与测量值一致为止。可使用勒让德级数展开式或高斯平均引数公式两种方法进行大地主题解算。实验数据证明该方法严密,易于编程实现。

An ellipsoid is usually chosen for data processing since observed space distance could not be used directly. This paper introduces a method to solve geodetic problem in condition of that the space distance and azimuth have been observed. An iterative method is adopted to convert the straight distance to the length of geodetic line. The space distance is assumed to be the initial length of geodetic line. Langrange progression expression or Gauss average argument can be used to solve geodetic problem. Then the space distance is calculated with coordinates. Refine of the length for geodetic line is done by the difference between calculated and observed space distance, and the geodetic problem should be solved again until that is small enough. This method is easy to be carried out in computer. The test data show it works well.