抗差Helmert估计在BDS/GPS组合定位权比分配中的应用

BDS与GPS双系统组合定位时，每个子系统需要进行定权，不同系统间的差异性会导致定权不准确。为提升组合定位精度，本文提出一种基于抗差Helmert方差分量估计的组合定位算法（RH算法）。首先，建立Helmert方差分量后验估计模型，区分多类型、不同精度的观测值，实现系统间权值的动态分配；然后，构建基于IGGⅢ方案的改进等价权函数，调整含粗差观测量的权值，解决观测值易存在粗差导致Helmert模型收敛失真的问题；最后，通过测试实际采集的双系统观测数据，验证算法的有效性和准确性。

Application of Robust Helmert Estimation in Weight Ratio Allocation of BDS/GPS Integrated Positioning

For the BDS/GPS integrated positioning system, each sub-system needs proper weight allocation, which, however, can be inaccurate due to the difference between systems. To improve the accuracy of the integrated positioning, this paper proposes an integrated positioning algorithm based on the robust Helmert-variance-component estimation, namely robust Helmert(RH). Firstly, we establish the Helmert-variance-component-posteriori estimation model. We distinguish the observed values with multi-type and different accuracy to achieve dynamic allocation of sub-system weight. Then, to adjust the weight of the observed values with gross errors, we construct an improved equivalent power function based on IGGⅢ scheme. This solves the convergence distortion problem in Helmert model owing to gross observation errors. Finally, by collecting and testing the actual data observed by the dual system, we verify the effectiveness and accuracy of the algorithm.