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Processing parameters for both PPP and differential solutions
| Parameter | PPP solution | Differential solution | |
|---|---|---|---|
| Dual frequency | Triple frequency | ||
| GNSS system | G, E, C | G, E, C | G |
| Observations | Code and phase | Code and phase | Code and phase |
| Mathematical model | Undifferenced ionosphere-free | Undifferenced ionosphere-free | Differenced |
| Frequency |
|
| L1/L2 |
| Sampling rate | 1 Hz | 1 Hz | 1 Hz |
| Elevation mask | 10° | 10° | 10° |
| Orbit and clock | CNES (RT) | CNES (RT) | IGS (final) |
| Tropospheric model | Saastamoinen model | ||
| Mapping function | Vienna mapping function 1 (VMF-1) | ||
| Parameter estimation | Kalman filter | ||
IMO accuracy requirements for GNSS positioning (IMO, 2002)
| Navigation phase | Horizontal accuracy (m) | Integrity | ||
|---|---|---|---|---|
| Alert limit (m) | Time to alarm (seconds) | Integrity risk (per 3 h) | ||
| Ocean | 10 | 25 | 10 | 10−5 |
| Coastal | 10 | 25 | 10 | 10−5 |
| Port approach | 10 | 25 | 10 | 10−5 |
| Inland waterways | 10 | 25 | 10 | 10−5 |
| Track control | 10 | 25 | 10 | 10−5 |
| In port navigation | 1 | 2.5 | 10 | 10−5 |
| Automatic docking | 0.1 | 0.25 | 10 | 10−5 |
Maximum 2D position error and 2D RMSE at 95% confidence for the PPP solutions
| PPP solution | Statistical parameter (m) | PPP solution | Statistical parameter | ||
|---|---|---|---|---|---|
| Maximum |
| Maximum |
| ||
| G-DF | 0.346 | 0.420 | G-TF | 0.162 | 0.265 |
| GE-DF | 0.215 | 0.242 | GE-TF | 0.149 | 0.190 |
| GC-DF | 0.236 | 0.279 | GC-TF | 0.243 | 0.314 |
| GEC-DF | 0.168 | 0.221 | GEC-TF | 0.221 | 0.175 |
Statistical analysis of 2D position for different PPP solutions
| PPP solution | Statistical parameter (m) | PPP solution | Statistical parameter (m) | ||
|---|---|---|---|---|---|
| Mean | RMSE | Mean | RMSE | ||
| G-DF | 0.140 | 0.172 | G-TF | 0.107 | 0.109 |
| GE-DF | 0.084 | 0.099 | GE-TF | 0.073 | 0.078 |
| GC-DF | 0.097 | 0.115 | GC-TF | 0.123 | 0.129 |
| GEC-DF | 0.064 | 0.085 | GEC-TF | 0.092 | 0.068 |