Acta Geodaetica et Cartographica Sinica ›› 2016, Vol. 45 ›› Issue (S2): 72-81.doi: 10.11947/j.AGCS.2016.F028

Previous Articles     Next Articles

BeiDou/GPS Displacement Detection Using Robust Weighting Based on Moving Window

ZHANG Yunlong1, YANG Songlin1, LUO Xiaoyan2, FANG Jianhong3, QIU Dongwei4   

  1. 1. School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China;
    2. Beijing Key Laboratory of Urban Spatial Information Engineering, Beijing Institute of Surveying and Mapping, Beijing 100038, China;
    3. Qinghai Research Institute of Transportation, Xining 810001, China;
    4. School of Surveying and Urban Spatial Information, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
  • Received:2016-11-25 Revised:2016-12-20 Online:2017-05-20 Published:2017-05-20
  • Supported by:

    The Beijing Key Laboratory of Urban Spatial Information Engineering (No. 2016101);The Science and Technology Project of MOHURD (No. 2015K8050)

Abstract:

The positioning accuracy of Kalman model under creep deformation condition is closely related to the observation variance, which can be affected by the accuracy of weight ratio of GPS and BDS observations. To improve displacement detection accuracy, shorten convergence time of initial coordinate and reduce monitoring cost, firstly the BDS/GPS single-frequency single-difference combination model is set up by using clock-synchronized dual-antenna BDS/GPS receiver. Then the equivalent weights of GPS and BDS observations are robustly determined respectively, and the Helmert variance component estimated by introducing time-correlated forgetting factor is used to achieve the precise weight ratio between GPS and BDS observations. Finally the coordinates are calculated using the extended Kalman filter by updating observed variance in real-time. According to the experiment, for the short baseline (1 km), BDS/GPS robust precise weighting Kalman method can shorten convergence time of initial coordinate significantly, which is suitable for monitoring the deformation body with creep characteristics, and the displacement detection accuracy can reach sub-millimeter level. Moreover the displacement convergence rate is inversely related to the length of moving window approximately.

Key words: BDS, GPS, single-frequency single-difference positioning model, robust precise weighting, displacement detection, sub-millimeter accuracy

CLC Number: