## 3 Results
### Comparative Analysis of PPP and Static Relative Methods in Urban Areas
a similar performance to geodetic dual-frequency receivers; however, it is less accurate. These results are expected since the low-cost receivers do not have antenna calibration parameters; however, the observation time was subjected to the recommendations of [26] for the convergence of the method. In Table 9, the absolute difference between each method is presented, which is expressed in m. The geodetic dual-frequency occupations (Est1-Est6) show a latitudinal and longitudinal difference less than 1.7 cm and 4.4 cm, respectively. The maximum differences shown by the geodetic single-frequency occupations (ISL1-ISL3) for longitude is about 40 cm. The low-cost receivers with double (LCDF) and single (LCSF) frequency show similar behavior, where the biggest difference established between them is in longitude. Such behavior could be related to the PPP positioning technique apparently. The coordinate estimations of ISL1-3, LCSF and LCDF stations showed maximum dispersions in longitude (\(\sigma\sim\)2 m). It showed the maximum difference in comparison with the relative positioning method with standard deviations less than 1 cm (Table 8) and a difference of less than 2.6 cm for the geodetic receiver between both techniques. Figure 13 shows the sum of the differences in coordinates (latitude and longitude) in m, where a large difference is found on the single frequency geodetic receiver (ISL1-3) and low-cost receivers (LCSF and LCDF). This may be due to the fact that the antenna of the low-cost GNSS receiver does not have an IGS calibration or circular polarized antenna (irregular gain pattern and low multipath suppression) [56]. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Station**} & \multicolumn{2}{c}{**PPP**} & \multicolumn{2}{c}{**Static Relative**} & \multicolumn{2}{c}{**Absolute Difference (m)**} \\ \cline{2-7}  & **Latitude \(\phi\)** & **Longitude \(\lambda\)** & **Latitude \(\phi\)** & **Longitude \(\lambda\)** & **Latitude \(\phi\)** & **Longitude \(\lambda\)** \\ \hline Est1 & 24\({}^{\circ}\)49\({}^{\prime}\)30.08338\({}^{\prime\prime}\) & 107\({}^{\circ}\)22\({}^{\prime}\)27.15461\({}^{\prime}\) & 24\({}^{\circ}\)49\({}^{\prime}\)30.08334\({  
Table 10 shows the results of the absolute differences of the orthometric, and ellipsoidal heights obtained from the PPP and static relative methods in m. The differences in orthometric heights for the dual-frequency geodetic receivers (Est1-Est6) show a maximum of 9 cm in the EST2 station. The values obtained in both methods are similar, they are not sensitive to the inclusion of the GGM10 model. The single-frequency geodetic receivers (ISL1-2), on the other hand, showed constant difference of 0.5 m.  
The low-cost receivers of single frequency (LCSF) show the greatest differences with less than 90 cm, which suggests that the solutions are not consistent with or without the GGM10 model. On the other hand, low-cost dual frequency (LCDF) receivers show 1 cm of absolute difference. This difference is due to the inclusion of the GGM10 model, as the difference is 2 mm when the GGM10 model is omitted. Through hours of positioning, it is possible to achieve precision for the vertical component up to 5 mm with the inclusion of high-quality antennas. Solutions of 10 mm were obtained in the vertical component in the case of static relative method in \(\sim\)2 h of observation time, using dual frequency low-cost antennas and the GGM10 model. The accuracies are low for the PPP method in both low-cost receivers, however, it presents better accuracy than the geodetic and low-cost single-frequency receivers as shown in Figure 14. The obtained PPP accuracy may be subject to signal degradation in the case of geodetic and low-cost single-frequency receivers (ISL1-3, LCSF) as well as a low-cost dual-frequency receivers (LCDF).