Comparative analysis of TEC in GNSS ionospheric tomography based on carrier phase smoothing pseudo-distance and precise single point positioning
The ionosphere is an important part of the Sun-Earth space environment,which has important influence on the modern radio engineering system and human space activities.Therefore,the monitoring and research of the ionosphere have important scientific significance for understanding the Sun-Earth space environment,revealing the formation and change mechanism of the ionosphere,and improving the accuracy of navigation and positioning.Using GNSS(Global Navigation Satellite System)to establish Computerized Ionospheric Tomography(CIT)model to invert the ionospheric structure,and to detect and study the ionospheric activity and its change rule is the current research hotspot.Among them,Carrier Phase Smoothing Pseudorange(CPSP)and Precise Point Positioning(PPP)are two main methods for obtaining ionospheric Total Electron Content(TEC),but the effects of these two methods on the performance of computerized ionospheric tomography model have not been compared and analyzed.In view of this,this paper uses the GNSS data of September 7 and September 8,2017 in the European region to obtain TEC for computerized ionospheric tomography inversion based on CPSP and PPP,respectively,and compare their accuracy.These two inversion methods are called CPSP-CIT and PPP-CIT,respectively.The results show that the mean RMSE between CPSP-CIT and the altimeter is 0.9292 × 1011 el/m3,and the mean RMSE between PPP-CIT and the altimeter is 0.6915 × 1011 el/m3.It can be seen that compared with CPSP-CIT,the accuracy of PPP-CIT is 25.6％higher.To further verify the accuracy of the above results,RMSE values of CPSP-CIT,PPP-CIT and Swarm satellite data were calculated respectively.The results showed that the average RMSE values between CPSP-CIT,PPP-CIT and Swarm satellite data were 0.4774 × 1011 el/m3 and 0.4275 × 1011 el/m3,respectively.The result shows that swarm between satellite data,the PPP-CIT precision compared with CPSP-CIT was 10.5％higher.In conclusion,the inversion accuracy of PPP-CIT is higher than that of CPSP-CIT,and its inversion results are closer to the measured data.
Ionospheric tomographyCarrier Phase Smoothing Pseudorange(CPSP)Precise Point Positioning(PPP)Ionosphere total electron content
NETL
NSTL
万方数据
