GPS双差基线模型的有偏估计解法研究

Research on Using the Biased Estimator to Resolve GPS Double-Difference Base-line Model

当GPS定位中设置历元间隔较小时,双差基线平差模型是严重病态的.此时,用最小二乘估计解算整周模糊度得不到正确解。为此,通常采用搜索法确定整周模糊度。但是搜索法一般要经过迭代求解过程,效率较低。尝试用有偏估计法直接解算GPS病态模型来获得较准确整周模糊度浮点解,从而为进一步固定整周未知数做必要准备。

If the intervals are too small in GPS surveying, the double-difference base-line model will be a very bad ill-conditioned and under this circumstances the ambiguity of the least squares estimation is no longer a group of good results. As a result the ambiguity resolution is usually acquired based on ambiguous search. But the searching methods commonly base on an iterative course, so these methods are inefficient. In this paper,the au- thor attempts to use biased estimator to resolve the ill-conditioned problems in GPS and acquire the float ambigui- ties which are necessary for acquiring the integer ambiguity.