基于伪卫星高精度定位的基坑支护位移变化感知

Displacement change perception of foundation pit support based on high- precision pseudolite positioning

为了进一步提升复杂施工环境基坑监测结果的准确性和提高自动化程度,本文采用伪卫星独立组网技术对基坑支护水平位置变化进行长期监测。首先,建立相对定位观测方程,基于已知点初始化方法固定出模糊度参数;其次,对相对定位中的载波双差多路径误差进行建模并修正;最后,利用无迹卡尔曼滤波(UKF)消除观测模型的线性化误差,获得最终的定位结果,并将该结果与真实位移进行比较。结果表明,伪卫星高精度定位系统可以有效感知基坑支护的微小位移,其绝对误差基本稳定在0.1 mm以内,平均相对误差约为10%。

In order to improve the accuracy and automation of the monitoring results under complex construction environment,the pseudolite independent networking technology was used to monitor the varieties in the horizontal position of foundation pit for a long time.Firstly,relative positioning observation equation is established and the ambiguity parameters is fixed based on the known point initialization method.Secondly,carrier double-difference multipath errors from relative positioning is modeled and corrected.Finally,the linearization error of the observation model is eliminated by using UKF to obtain the final positioning result,and this result is compared with the real displacement.The results show that the high-precision pseudolite positioning system can be used to effectively perceive the small displacement of foundation pit support,and its absolute error is basically within 0.1 mm,and the average relative error is about 10%.