# Assessment of BeiDou-3 and Multi-GNSS Precise Point Positioning Performance
## 5 Data Tests and Results Analysis
### Positioning Accuracy and Convergence Time
#### 5.1.2 Kinematic PPP Results and Analysis  
Similar to the static PPP processing, the kinematic PPP processing results for 12 different processing cases are presented and analyzed in this section. The PPP kinematic test was conducted by using real observation data that were collected at 16 stations over 30 days. Figures 7 and 8 show the kinematic PPP positioning errors, the number of visual satellite and PDOP at KUN1 for GPS-only, BDS-2-only, BDS-2/BDS-3, GLONASS-only, Galileo-only, and GPS/BDS-2/BDS-3/GLONASS/Galileo, respectively. Unlike BROCH, the change of the BDS-2-only PDOP of KUN1 is relatively stable, without significant anomaly distortion. As described in Section 4, the BDS-2 service area is mainly centered in the Asia-Pacific region where its GEO satellites and IGSO satellites are mainly concentrated, KUN1 can receive the enough the health signals of BDS-2. There are still obvious gaps between BDS-2 and other navigation system with the enough the health signals of BDS-2 when we compared the kinematic positioning accuracy of BDS-2 and other navigation system. When using the observations of BDS-3, the kinematic positioning accuracy of BDS-2/BDS-3 has been improved obviously compared BDS-2-only kinematic PPP, and there is no obvious noise. The above analyses clearly show that the performance of BDS has been greatly improved with the open service of the global basic navigation service of BDS-3. Similar to static positioning, GPS, BDS-2/BDS-3, GLONASS, and Galileo have all achieved good convergence effect, and multi-GNSS increases the positioning accuracy and the stability of positioning and reduces the convergence time over the single-constellation and dual-constellation PPP. Figure 6: The convergence time for GPS-only, BDS-2-only, BDS-2/BDS-3, GLONASS-only, Galileo-only, GPS/BDS-2/BDS-3, GPS/GLONASS, GPS/Galileo, BDS-2/BDS-3/GLONASS, BDS-2/BDS-3/Galileo, GLONASS/Galileo, and GPS/BDS-2/BDS-3/GLONASS/Galileo static PPP processing using real observation data collected at 16 stations over 30 days. Table 3 provides the RMS and convergence time in order to assess the performance of the kinematic positioning. The RMS statistical method of kinematic PPP and the convergence criterion are the same as static PPP. We can draw the following viewpoints based on the solutions of the selected observation data. The kinematic BDS-2/BDS-3 PPP improves the position accuracy by 26.32%, 36.00%, and 35.94% and it reduces convergence time by 19.32%, 14.07%, and 19.86% over the BDS-2-only PPP in three  
Figure 8: Number of satellite and PDOP at KUN1 for GPS-only, BDS-2-only, BDS-2/BDS-3, GLONASS-only, Galileo-only, and GPS/BDS-2/BDS-3/GLONASS/Galileo on DOY 024 in 2019. Figure 7: Kinematic PPP positioning errors at KUN1 for 12 different processing cases on DOY 024 in 2019.  
coordinate components, respectively. From the perspective of the positioning accuracy and convergence time, there is no significant difference between BDS-2/BDS-3, Galileo, and GPS, GLONASS. BDS and Galileo can improve multi-GNSS positioning accuracy. With the combination of BDS-2/BDS-3 and GPS, the positioning accuracy is improved by 21.59%, 17.47%, and 15.17% and the convergence time is reduced by 35.14%, 8.73%, and 18.49% over the GPS-only case in the three coordinate components, respectively. The GPS/Galileo combined PPP improves the positioning accuracy by 26.36%, 22.10%, and 22.19% and it reduces the convergence time by 32.13%, 24.67%, and 26.19% over the GPS-only PPP in three coordinate components, respectively. Whether positioning accuracy or convergence time, the performance of GPS/BDS-2/BDS-3/GLONASS/Galileo PPP is superior to the single-constellation and dual-constellation PPP. The effect of multi-GNSS to improve the positioning accuracy and reduce convergence time is more obvious in kinematic positioning. When considering that the receiver coordinates are estimated as white noise process, the receiver coordinate parameters cannot be constrained by the explicit kinematics model as in the static processing mode.