基于三频观测的Multi_GNSS载波相位特性分析

Analysis on Multi-GNSS Carrier Phase Characteristics Based on Triple-frequency Observations

载波相位观测噪声和多径误差是衡量载波相位观测数据质量的重要指标。采用三频消电离层无几何组合对GPS、BDS和Galileo系统的载波相位观测噪声和多径误差进行计算。选取IGS ARHT和MGO2两测站2021年连续30 d的数据,对上述GNSS系统的载波相位观测噪声和多径误差特性进行了分析,采用高阶谐函数对GPS Block IIF卫星的频间钟偏差进行模型化以降低其对DIF的影响,结论显示,各系统的DIF组合均方根值随着仰角的增大逐渐减小,在高仰角区间内比低仰角区间下降约90%;受残余IFCB的影响,GPS系统的DIF组合均方根值最大,约为BDS-2系统的3—7倍,约为BDS-3和GAL系统的20倍。

The multi-path effects and measurement noise are important indexes in GNSS carrier phase quality checking and can be cal-culated using the Differenced Ionosphere-free Linear Combination(DIF).Carrier phase observation noise and multi-path errors for GPS,BDS and Galileo systems are normally calculated by a three frequency ionospheric non geometric combination.30 consecutive days observations of IGS station ARHT and MGO2 are collected and the DIF combinations of GPS,BDS-2,BDS-3 and Galileo are analyzed.It can be concluded that the DIF RMS of the four GNSSs reduce along with the growth of elevation and the decline range can reach up to 90%compared with the low elevation section and the high elevation section.Because of the IFCB residuals,the DIF RMS of GPS is the largest among the four GNSSs,which is 3—7 times of that of BDS-2 and 20 times of BDS-3 and Galileo.