摘要
根据拟合推估两步极小解法的基本原理,将随机场分为趋势性和随机性两部分,对趋势性部分采用函数模型拟合后,用剩余残差拟合随机性信号协方差函数,再求解趋势性模型参数和随机信号。探讨了该方法在地图坐标变换中的应用,结果表明,基于两步极小的拟合推估新解法的结果明显优于最小二乘的结果。
After having reviewed the basic collocation theory, the principle of the collocation by two minimization steps is introduced. Considering that the stochastic signal contains not only the stochastic information but also some systematic trend, after the systematic trend parameter having been calculated and then the residual was used to compute the covariance function of the stochastic information. With the refitted covariance function, the stochastic signal was evaluated and the systematic trend parameters were estimated again. An actual digital map case shows that the solution accuracy with this method for collocation is better than that with the affine transformation by least squares.
出处
《大地测量与地球动力学》
CSCD
北大核心
2008年第1期81-84,共4页
Journal of Geodesy and Geodynamics
基金
国家自然科学基金(40774001和40474001)
地球空间与大地测量教育部重点实验室开放基金(1469990324233-04-11)
关键词
拟合推估
协方差函数
两步极小
数字化地图
坐标变换
collocation
covariance function
two minimization steps
digital maps
coordinate transformation
