GPS变形监测的位移显著性检验方法研究

Research on the test method of displacement significance in GPS deformation monitoring

目前普遍采用的位移显著性检验方法,是人为地将客观上的空间位移问题转化为地方(局部)坐标系中的1维或2维位移问题来进行检验,既使位移检验在理论上的严密性受到损害,又使GPS能够在协议地球坐标系(ITRF或WGS-84)中同时精确测定空间3维位移的优越性得不到充分利用。由于在位移转换过程中会引入误差,可能导致位移显著性检验结果不可靠,尤其是当位移量小而坐标转换误差大时可靠性更低。为了避免由于位移转换存在误差而影响位移显著性检验结果的可靠性,本文提出了用GPS进行变形监测时,直接在ITRF或WGS-84空间坐标参考框架下进行位移显著性检验的新方法—"变形误差椭球检验法",严密地推导了有关理论公式,给出了具体的检验方法,并进行了实例计算和分析。

The method that widely used for displacement test at present is to artificially transform objective spatial displacement to one-dimensional or two-dimensional displacement in local coordinate system. This not only damages the theoretical strictness of displacement test but also makes it impossible to fully use the superiority that GPS can simultaneously and accurately measure three-dimensional displacements in the agreement globe coordinate system （ ITRF or WGS-84 ） in deformation analysis. In addition, errors can be caused in the process of displacement transformation, which may result in incorrect test result. To avoid the effect of displacement transformation error on the test result of displacement significance, this paper puts forward a new method-- ＂Deformation Error Ellipsoid Test Method＂ , by which displacement significance is tested directly in ITRF or WGS-84 when GPS is used for deformation monitoring. The strict theoretical formulae for deformation error ellipsoid test and a realistic case of displacement test are given.