变异系数赋权法确定GNSS系统硬件延迟

A Variation Coefficient Weighting Method to Determine the Difference Code Bias Estimation of GNSS System

采用平均实时去噪分离方法处理相位平滑伪距数据,研究GNSS系统硬件延迟估计的随机模型。针对高度角定权、等精度定权等经验定权法参数估计不客观的问题,选取高度角平方和相位平滑值作为质量指标,提出变异系数赋权法,该方法能够顾及观测值的多种随机影响因素,具有较强的数学理论基础。实验结果表明:1)模型拟合精度与观测数据和测站位置有关,测站位置电离层周日变化越平稳、观测数据越充足,模型拟合精度越好;2)变异系数赋权法计算的模型拟合精度优于高度角定权法;3)在参数估计的精度和稳定性方面,变异系数赋权法优于高度角定权法,单天数据的解算精度提高0.2 ns。

This paper studies the stochastic model of DCB for GNSS systems by post-processing phase smoothed code data. To resolve the problem of estimating the uncertainty of the parameters of the weight of the elevation angle and the equal-accuracy, the paper presents a weighted method, i.e., variation coefficient weighting, to effectively influence the stochastic model. The index weights are determined according to the decision matrix of the index value of the evaluation object. Preliminary results show that: 1) The fitting precision of the model is related to observation data and the station location. The more stable the ionospheric variation of the station position and the adequacy of the observational data, the better the model fitting accuracy. 2) The model fitting accuracy is better than by the weight of elevation angle using variation coefficient weighting. 3) In the accuracy and stability of parameter estimation, the variation coefficient weighting method is superior to the method of the weight of elevation angle, and the calculation accuracy of single-day data can be improved by 0.2 ns.