Real-Time GPS/Galileo Precise Point Positioning Using NAVCAST Real-Time Corrections

Abstract

Real-time precise point positioning (PPP) is possible through the use of real-time precise satellite orbit and clock corrections, which are available through a number of organizations including the International GNSS Service (IGS) real-time service (IGS-RTS). Unfortunately, IGS-RTS is only available for the GPS and GLONASS constellations. In 2018, a new real-time service, NAVCAST, which provides real-time precise orbit and clock corrections for the GPS and Galileo constellations, was launched. In this research, the potential performance of real-time PPP which makes use of NAVCAST real-time corrections is analyzed using various static and kinematic datasets. In the static dataset, 24 hours of observations from eight IGS stations in Canada over three different days were utilized. The static results show that the contribution of Galileo satellites can improve the positioning accuracy, with 30%, 34%, and 31% in east, north, and up directions compared to the GPS-only counterparts. In addition, centimeter-level positioning accuracy in the horizontal direction and decimeter-level positioning accuracy in the vertical direction can be achieved by adding Galileo observations. In the kinematic dataset, a real vehicular test was conducted in urban and suburban combined areas. The real-time kinematic GPS/Galileo PPP solutions demonstrate an improvement of about 53%, 45%, and 70% in east, north, and up directions compared to the GPS-only counterparts. It is shown that the real-time GPS/Galileo PPP can achieve a sub-decimeter horizontal positioning accuracy and about meter-level vertical positioning accuracy through the use of NAVCAST real-time corrections.

Kinematic Galileo and GPS Performances in Aerial, Terrestrial, and Maritime Environments

“…Starting from Q3 2019 campaign, the Galileo E1 E5b standard deviation values for the extra-urban surveys are lower than 0.28 m for the horizontal component and lower than 0.64 m for the vertical component. The horizontal values meet those required for a road-transportation domain according to the GSA Market Report Issue 6, 2019 [22], see Table 2. Figure 15 presents the results of the comparison between the reference solution and the triple-frequency differential solutions (GPS and Galileo) for the two types of antennas.…”

“…Starting from Q3 2019 campaign, the Galileo E1 E5b standard deviation values for the extra-urban surveys are lower than 0.28 m for the horizontal component and lower than 0.64 m for the vertical component. The horizontal values meet those required for a road-transportation domain according to the GSA Market Report Issue 6, 2019 [22], see Table 2.…”

“…The navigation phases during the maritime campaigns presented in this paper were: coastal navigation (accuracy requirements up to 10 m), port navigation, and port approach, (accuracy requirements between 1 and 10 m) according to IMO A.915 (22) [30].…”

“…It is stated that the Galileo system is characterized by a better planimetric performance with respect to the other systems, referred to by the reference trajectory [6]. The results of a vehicular test conducted in urban and suburban areas, with real-time computed kinematic GPS/Galileo PPP solutions, are presented in [22]. It was revealed that the GPS/Galileo solution had improvements of more than 45% in the east, north, and up directions, compared to the GPS-only solution.…”

Multi-sensor Integration for Land Vehicular Navigation

“…Precise point positioning (PPP) has been widely used in autonomous positioning (AP) because of its ability to provide positioning accuracy at the decimeter-level (Abd Rabbou and El-Rabbany, 2015b, Cai et al, 2015, Li et al, 2015b. PPP accuracy has improved through a combination of measurements from multiple GNSS systems such as GPS+Galileo (Elmezayen and El-Rabbany, 2019c), GPS+GLONASS (Cai and Gao, 2013), GPS+Galileo+GLONASS (Afifi and El-Rabbany, 2016), and GPS+Galileo+GLONASS+BeiDou (Cai et al, 2015). Precise real-time GNSS orbit and clock corrections have also been made available from a number of organizations, such as the international GNSS service (IGS) (IGS, 2019, Wang et al, 2018a as well as other analysis centers (Wang et al, 2018b).…”