Railroads and the Rail Traffic Control Systems installed on them in Poland have recently been undergoing rapid technological development (Brodzik, 2019). Modern transportation solutions are susceptible to electromagnetic interference (Paś and Rosiński, 2017). Development of modern railroad infrastructure means not only stations and modern rolling stock, but also safe and reliable train traffic control systems based on the latest telecommunication and IT technologies (Ciszewski et al., 2017). In the last century these technologies were still considered dangerous and were introduced with great fear. Today, computerized systems for controlling railway traffic on the track are becoming the norm. Systems are created as "overlays" for existing relay systems or autonomous systems are built based on microprocessor systems (Burdzik et al., 2017). Today it is hard to imagine a modern control room without computer equipment. The introduction of microprocessor technology to railroad traffic control devices took place at the turn of the century. However, the use of modern radio systems in rail transport is the moment when technology based on the appeared in the world LTE (Long-Term evolution) standard. The development of modern data transmission technologies is integrally connected with the mobility of its users. In the presented article the author has tried to determine the impact of transmission synchronization on the basic transmission parameters of LTE signal (Chrzan, 2021). The convenience of using rail communications for its users is the possibility of uninterrupted access to data transmission services along the entire route of the train. Therefore, the research presented in this article was focused on the use of the public radio communication network for passenger data transmission and data transmission for railroad needs.
The article presents the influence of synchronisation of data transmission in open railway systems using GPS (Global Positioning System) technology. It presents a description of the physical phenomena associated with synchronisation, and presents the author's method for carrying out measurements on railway line No. 4. For this purpose, a diagnostic station was built and special software for data transmission encryption was prepared. The process of synchronisation of clocks with the use of uniform time was adopted as the basis. General measurement results and conclusions resulting from the use of open transmission in railway radiocommunication systems synchronised by the GPS system signal are presented.
