# PPP and PPP-AR Kinematic Post-Processed Performance of GPS-Only, Galileo-Only and Multi-GNSS
## 2 Materials and Methods
\begin{table}
\begin{tabular}{c c} \hline \hline \multicolumn{2}{c}{**Processing Strategy**} \\ \hline Software & GINS, DYNAMO, EXE\_PPP [21] \\ \hline Strategy & PPP, PPP-AR zero-difference \\ \hline Estimation & Static with Kalman, 300 s sampling \\ \hline \multicolumn{2}{c}{**Orbit, Clocks and Satellites Biaises**} \\ \hline Orbits and clocks & CNES-CLS orbits (’grg’) [8] \\ \hline Satellite biases & CNES-CLS wide-lane satellite biases [22] \\ \hline GNSS relative weighting & Equal weighting for GPS and Galileo \\ \hline GNSS measurement sigmas & Code: 60 cm; Phase: 3.5 mm \\ (at 0\({}^{\circ}\) of elevation) & \\ \hline Elevation cut-off & 8 deg \\ \hline Elevation weighting function, & \(\sigma(\delta)=\frac{0.0035}{0.15+0.85\sin\delta}\) \\ \hline \multicolumn{2}{c}{**Models for Processing**} \\ \hline Antenna phase center corrections & ANTEX14 PCO/PCV [23] \\ \hline \multicolumn{2}{c}{VMF1 [24] + GPT2 [25] (A priori local meteorological parameters (pressure, temperature, and wet mapping function coefficients) of GPT2 model are used to compute hydrostatic delays and for the wet mapping function VMF1. We then adjust 1 zenithal tropospheric delay per two hours in factor of the wet mapping function).} \\ \hline Ionosphere model & Ionosphere-free combination and second ordercorrections [26] \\ \hline Reference frame & ITRF 2014 [27] \\ \hline Attitude model & Kouba [28] for GPS and GSA [23] for Galileo \\ \hline Ocean loading effects & FES2012 [29] \\ \hline Earth orientation modelling & IERS Conventions 2010 [30] \\ \hline Earth orientation parameters & EOP C04 [31] \\ \hline Phase windup & Models used by Kouba [28] \\ \hline \multicolumn{2}{c}{**Estimated Parameters**} \\ \hline \multicolumn{2}{c}{Troposphere} & 1 ZTD/2 h, 1 pair of gradients (E, N)/day (1 couple of gradients in north and east direction are also adjusted per day following [31; 32] \\ \hline Observation sampling & 300 s \\ \hline Inter-system biases (phase obs.) & 1 per station (zero mean condition) \\ \hline Station coordinates estimates & X, Y, Z transformed to East, North, Up \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Parameters, models and strategy of experiments. For the experimentation, one week of data (11-17 February 2019, Day of Year (DOY): 42-49/2019) is chosen. During that period, 31 GPS satellites and 24 Galileo satellites (including the ecliptic E14 and E18) were processed. All models and processing parameters and given in Table 2.  
The IGS compiles a consistent set of absolute Antenna Phase Centre (APC) (i.e., Phase Center Offset (PCO) and Phase Center Variation (PCV)) corrections for both ground stations and satellites antennas, which are provided in so-called the Antenna Exchange Format (ANTEX) files [20]. These are very important for the calculation of the geometrical distance between satellite and receiver. For the APC corrections, it was decided to use the ANTEX14 file from the IGS. During the processing of the present article, ANTEX14 file included the APC values of the receivers for GPS L1/L2 frequencies, but not of Galileo E1/E5a frequencies. Delivery of the respective receiver APC values for the Galileo E1/E5a frequencies was underway from the IGS Antenna WG [33]. For the ambiguity fixing step biases, we do not use any additional bias for Galileo ambiguity fixing since a previous study [6] showed that the Galileo \(\mu^{s}\) biases were compatible with all kind of receivers and modulations (such as L1C, L1W, L1X, etc. ).