GPS/伪卫星技术在露天矿边坡监测中的应用

GPS/pseudolites technology for the slope deformation monitoring in open-pit mine

针对露天矿区GPS可视卫星个数和几何图形条件易受到较大坡度的遮挡影响,利用GPS/伪卫星(PLs)组合定位技术,增强卫星的几何强度。同时,为了削弱非建模系统误差的影响,提出通过经验模态分解(EMD)的多尺度分解与重构结构,依据累积标准化模量的均值随尺幅的变化确定系统误差与噪声分离尺度的选择标准,建立系统趋势分离模型。通过模拟仿真和实验分析表明:选择合适的PLs的设站位置,GPS/PLs组合定位技术可较大程度地改善定位精度因子(DOP);利用EMD方法去除非建模系统误差后,GPS/PLs组合观测值的双差残差序列的系统误差很大程度上得到削弱;可靠性检验指数F-ratio和W-ratio分别达到7.79和91.83,整周模糊度固定解的可靠性明显增强;基线向量解的精度也得到明显提高,X、Y、Z坐标分量的标准差为0.1、0.1、0.3mm。

In order to improve positioning geometry strength and to increase the number of GPS satellites in open-pit mine,integration GPS/Pseudolites（PLs） positioning technology was proposed. However,the un-modeled systematic errors were still the main limiting factors for high precision baseline solution,wherefore the Empirical Mode Decomposition （EMD） theory was employed to eliminate the error. The multi-scale decomposition and reconstruction architecture were defined here on the basis of the EMD theory and the systematic error mitigation model was demonstrated as well. A standards of the scale selection for the systematic error elimination was given in terms of the mean of the accumulated standardized modes. Thereafter,the scheme of the GPS/PLs baseline solution based on the EMD was suggested. The simulation and experiment results show that the Dilution of Precision （DOP） are reduced greater degree when PLs is located suitable and the reliability of ambiguity resolution is dramatically improved with the reliability indices F-ratio and W-ratio reach 7. 79 and 91. 83 after systematic error eliminated. The proposed scheme dramatically improves the precision of baseline vector,standard deviation in X,Y,Z are 0. 1,0. 1,0. 3 mm respectively.