电离层P4观测值的限差分析与应用

Limited Error Analysis and Application of P4 Observation in the Ionosphere

P4观测值为双频码组合电离层观测值，是利用GNSS技术建立电离层VTEC模型的主要观测量之一。基于IGS长时间序列VTEC产品和已有研究结果，分析了P4观测值的限差值，提出了利用该限差值对P4观测值进行粗差检验，并进行了多IGS站不同电离层活跃期的检核。应用结果初步表明所给出的P4限差值具有适应性与合理性，从而为P4观测值乃至原始伪距观测值的质量分析提供了新方法。

As a combined ionosphere observation of dual-frequency code, P4 observation is a main observation for establishing ionospheric VTEC model using GNSS technology. The limited error of P4 is analyzed based on IGS long time series VTEC products, a gross error checking method of P4 observation using the limited error is proposed and P4 observation of multiple IGS stations in different ionospheric active period have been checked. The results show that the limited error of P4 observation is reasonable and a- daptable, which can provide a new method for quality analysis of P4 observation and the original pseudorange observation.