is the time needed to start fixing integer ambiguities, typically around 20-30 min. This long time is attributed to the pseudorange measurement noise, satellite geometry, multipath due to surrounding environ ment, and receiver and antenna quality (El-Mowafy 2014, Seepersad and Bisnath 2014).In PPP-AR, satellite uncalibrated phase delay (UPD) is required to separate the float carrier phase ambiguities from their integer values and fix the latter. This improves the positioning accuracy from the decimetre level, achievable with standard float PPP, to the centimetre (cm) level (Laurichesse