|
| Item | Models |
|
| Constellation | GPS, Galileo, BDS-2, BDS-3 |
| Observations | Raw carrier phase and code observations |
| Estimator | Extended Kalman filter |
| Frequency selection | GPS:L1/L2/L5; Galileo:E1/E5a/E6/E5b; BDS-2:B1I/B2I/B3I; BDS-3:BIc/B1I/B2a/B3I |
| Elevation cutoff angle | 10° |
| Sampling rate | 30 s |
| Weighting scheme | Elevation-dependent weight: For GPS/galileo/BDS-3 and IGSO/MEO of BDS-2, adopt 3 mm and 0.3 m for raw phase and code, respectively; for GEO of BDS-2, adopt 1 cm and 1m for raw phase and code, respectively |
| Ionospheric delay | Estimated as random-walk process [16] |
| Tropospheric delay | Dry component: corrected with GPT model [34] |
| Wet component: estimated as random-walk process (10−8m2/s) |
| Mapping function: GMF [35] |
|
| Sagnac effect | Applied |
| Station displacement | Corrected by IERS convention 2010 [36] |
| Satellite antenna PCO/PCV | PCO/PCV values from IGS14_2080.atx are used |
| Receiver antenna PCO/PCV | For GPS, L1/L2 PCO/PCV values from IGS14.atx are used, use L2 parameters to correct L5; |
| For Galileo, use GPS L1 values to correct E1, use GPS L2 values to correct E5a/E6/E5b; |
| For BDS-2, use GPS L1 values to correct B1I, use GPS L2 values to correct B2I/B3I; |
| For BDS-3, use GPS L1 values to correct B1c/B1I, use GPS L2 values to correct B2a/B3I |
|
| Phase wind-up effect | Corrected [37] |
| IFCB | Only applied for satellites of GPS Block IIF and BDS-2 |
| Satellite DCB | Corrected with MGEX DCB products [38] |
| Receiver IFB | Estimated as daily constants |
| Receiver clock | Estimated as white noise process (1002 m2) |
| Phase ambiguity | Estimated, constant for each continuous arcs |
| Ratio | 2.0 |
|
