分析了卫星星座PDOP值与卫星数的关系以及伪距和载波相位观测值残差量级的大小,结合精密单点定位各参数的特性,提出一种适用于精密单点定位的分类因子抗差自适应滤波法。该方法在等价权函数的选取上兼顾PDOP值的检验,并对不同观测量分别进行抗差等价权替换。根据不同参数的特性,建立分类自适应因子,利用预测残差求取各类参数的自适应因子。实验表明,该方法不仅能检测和控制异常观测量对定位解算的影响,而且能提高PPP定位的精度及可靠性。
We discuss the relationship between the PDOP value of satellite constellation and satellite number and analyze the magnitudes of the residual errors of pseudo-range and carrier phase observations value.We propose a classification factor robust adaptive filtering method.This method is applied for precise point positioning and the equivalent replacement is based on observation of the different values.At the same time,the adaptive factor is set up according to the characteristics of different parameters and calculated by the prediction residual.Experiments show that this method can not only detect and control the influence of the abnormal values,but can also improve the accuracy and reliability of PPP.