单双频GPS混合观测高精度单频精密单点定位

Mixed Application of Single and Dual Frequency Receivers in Single-Frequency Precise Point Positioning

精密单点定位不受局域观测和设施影响,有利于形变监测。为降低电离层延迟对单频精密单点定位结果的影响,提出了单双频混合观测的方法。但单频精密单点定位仍受相位非小数偏差影响,为此提出采用双差模糊度应用于单频精密单点定位。观测数据解算结果表明,电离层延迟精度优于1 cm,满足单频精密单点高精度定位的要求,对应的单频精密单点定位可实现厘米级结果。双差模糊度应用于单频精密单点定位时,参数收敛时间平均缩短约7 min,在北、东、高程3个方向的定位结果平均分别提升0.23、0.14、0.21 cm。

Precise point positioning(PPP)is not affected by the local observation and infrastructure which is beneficial for deformation monitoring.Considering the influence of the ionospheric delay on single-frequency point positioning,the method of the mixed application of the single and dual frequency observations is proposed.However,the single-frequency precise point positioning is affected by the fractional bias of phase observation.The method for introducing the dual-differenced ambiguity into single-frequency precise point positioning is discussed.The data are processed using the method proposed.The results show that the estimated ionospheric delay is higher than 1 cm which can meet the requirement of single-frequency point positioning.It is noticed that the convergence time can be shortened for an average improvement of 7 minutes.The improvements for the single-frequency point positioning in the directions of the North,East,and UP can reach 0.23,0.14,and 0.21 cm,respectively.