In this paper,we develop an approach to study the effect of second-order ionospheric delay on GPS positioning based on the ionosphere-free combination (abbreviated to Lc) of GPS dual-frequency carrier phase observable...In this paper,we develop an approach to study the effect of second-order ionospheric delay on GPS positioning based on the ionosphere-free combination (abbreviated to Lc) of GPS dual-frequency carrier phase observables,in which the first-order ionospheric delay has been eliminated.GPS data from IGS WUHN tracking station during April 9 23,2003 is used to perform the above approach,and results show that the second-order ionospheric delay in GPS so-called ionosphere-free observables will result in the regular southward shift of GPS positioning solution.Additionally,the influence of the Earth's magnetic field on second-order ionospheric delay over the Wuhan area is discussed,and it indicates that the Earth's magnetic field is one of the main factors why second-order ionospheric delay results in the regular southward shift of GPS positioning solution over Wuhan area.展开更多
基金supported by the National Science Foundation for Distinguished Young Scholars (Grant No. 40625013)the National Natural Science Foundation of China (Grant No. 40890160)+1 种基金the National High-Tech Research and Development Program of China (Grant No. 2007AA12Z311)the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No.0909141014)
文摘In this paper,we develop an approach to study the effect of second-order ionospheric delay on GPS positioning based on the ionosphere-free combination (abbreviated to Lc) of GPS dual-frequency carrier phase observables,in which the first-order ionospheric delay has been eliminated.GPS data from IGS WUHN tracking station during April 9 23,2003 is used to perform the above approach,and results show that the second-order ionospheric delay in GPS so-called ionosphere-free observables will result in the regular southward shift of GPS positioning solution.Additionally,the influence of the Earth's magnetic field on second-order ionospheric delay over the Wuhan area is discussed,and it indicates that the Earth's magnetic field is one of the main factors why second-order ionospheric delay results in the regular southward shift of GPS positioning solution over Wuhan area.