1. Application of Satellite Positioning in Railway

Satellite navigation system is a satellite system that covers global space to realize positioning. It determines its position through electronic receiver, namely longitude, latitude, and altitude, and ensures that the time signal transmitted through satellite broadcasting is within the error range of 10 m. Each satellite navigation system covering the globe is usually composed of a constellation of 20–30 satellites, spreading over several orbital planes. In the actual system, the number of satellites in each satellite navigation system is not identical, but the satellite orbital tilt is greater than 50°, the orbital period is about 12 h, the height is about 20,000 km distance from the surface of the earth (Han in J Shenzhen Univ (Sci & Eng) 6(1):105–12, 1989 [1]. Figure 1.1 shows a schematic of a satellite in orbit. The satellite navigation system has the characteristics of all-weather positioning, global positioning, three-dimensional high-precision positioning, and dynamic navigation, so it has a wide range of applications.