Mobile Satellite Measurements in Designing and Exploitation of Rail Roads

The article presents a summary of several years (2009-2015) of studies on the application of mobile satellite Global Navigation Satellite Systems (GNSS) measurements in the field of designing and operation of railways. These studies have been conducted by an interdisciplinary research team from the Gdansk University of Technology and the Gdynia Maritime University. Mobile satellite GNSS measurements are taken during a ride (through the railroad) by the measuring train consist of motor car with a trailed double axles platform bogies on which the GNSS receivers were installed. The authors described the adopted methodology of the carried out measurements of the rail and tram tracks. The problem of an accuracy of satellite positioning measurements has been discussed.The authors proposed a method that makes it possible to assess quantitatively the accuracy of the research implemented over years. New concepts were introduced, such as: GNSS positioning networking service availability, reliability and continuity based on the theory of reliability. Using a developed mathematical model they recounted the results of four archival measurement campaigns of years: 2009-2015. The studies have shown that the number of used satellite systems as well as support for GNSS measurements with the inertial system are important from the point of view of the accuracy of the results.