# Mitigating the Scintillation Effect on GNSS Signals Using MP and ROTI
## 3 Results
### Statistical Results  
#### 3.2.1 Satellite Removal Strategy  
The change of height and 3D positioning errors (RMSE) after removing scintillation-affected satellites based on MPI, MP2, ROTI, S4 and \(\sigma_{\phi}\) on 14 days at 3 stations are summarized in Tables 1-3. The improved RMSEs are highlighted in bold. It was observed that the satellite removal strategy based on MP1, MP2, ROTI and \(\sigma_{\phi}\) improved the positioning error on 7, 8, 6 and 5 days, respectively, within 14 days, while S4 improved the positioning error on 2 of the 7 days. The effectiveness of scintillation parameters was not higher than that of standard parameters, where S4 is the least effective parameter. Additionally, the situation exists that removing satellites based on MP can improve the error while using the other parameters cannot, and vice versa. Furthermore, the height and 3D errors were not always improved simultaneously. The error was improved on 8 out of 14 days at most, but most improvements were less than 0.05 m or even 0.01 m, where most of the original errors were at the decimeter level. Hence it can be concluded that the satellite removal strategy was not effective. Figure 10: Comparison between the original and weighted RMSE of the (**a**) PPP height error based on S4 and \(\sigma_{\phi}\), (**b**) PPP height error based on MPF and ROTI, (**c**) PPP 3D error based on S4 and \(\sigma_{\phi}\), (**d**) PPP 3D error based on MPF and ROTI. Units as in Figure 4. The period affected by scintillation is framed in a rectangle. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Station**} & \multirow{2}{*}{**Date**} & \multicolumn{2}{c}{**Original RMSE**} & \multirow{2}{*}{**Reference**} & \multirow{2}{*}{**Satellite-Removed RMSE**} \\ \cline{3-3} \cline{5-6}  & & & & & **Parameters** & **Satellite** & **Height** & **3D** \\ \hline \multirow{8}{*}{**SAOOP**} & \multirow{8}{*}{0.0144} & \multirow{8}{*}{0.0180} & \multirow{8}{*}{0.6422} & MP1 & G25 & 0.0178 & 0.0199 \\ \cline{4-7}  & & & & & MP2 & G5 & **0.0127** & **0.0139** \\ \cline{4-7}  & \multirow{2}{*}{2017} & & & & ROTI & G20 & **0.0141** & **0.0168** \\ \cline{4-7}  & & & & & S4 & & \\ \cline{4-7}  & & & & & \(\sigma_{\Phi}\) & G21 & 0.0144 & 0.0180 \\ \cline{4-7}  & \multirow{8}{*}{0.6245} & & & & MP1 & & \\ \cline{4-7}  & & & & & S4 & & \\ \cline{4-7}  & \multirow{8}{*}{0.6245} & & & & MP1 & & \\ \cline{4-7}  & & & & & S4 & & \\ \cline{4-7}  & & & & & ROTI & & & \\ \cline{4-7}  & \multirow{8}{*}{0.1395} & & & & MP1 & & \\ \cline{4-7}  & & & & MP2 & & & \\ \cline{4-7}  & \multirow{8}{*}{0.1395} & & & & S4 & & \\ \cline{4-7}  & & & & MP2 & & & \\ \cline{4-7}  & & & & S4 & & & \\ \cline{4-7}  & \multirow{8}{*}{0.0219} & & & & MP2 & & \\ \cline{4-7}  & & & & & S4 & & \\ \cline{4-7}  & & & & & ROTI & & & \\ \cline{4-7}  & & & & MP1 & & & \\ \cline{4-7}  & \multirow{8}{*}{0.0217} & & & MP2 & & & \\ \cline{4-7}  & & & & MP2 & & & \\ \cline{4-7}  & & & & S4 & & & \\ \cline{4-7}  & \multirow{8}{*}{0.0311} & & & MP1 & & & \\ \cline{4-7}  & & & & MP2 & & & \\ \cline{4-7}  & & & & S4 & & & \\ \cline{4-7}  & & & & S4 & & & \\ \cline{4-7}  & \multirow{8}{*}{0.0324} & & & MP1 & & & \\ \cline{4-7}  & & & & MP2 & & & \\ \cline{4-7}  & & & & MP1 & & & \\ \cline{4-7}  & & & & MP1 & & & \\ \cline{4-7}  & &