Current Status and Development Trend of Communication and signaling Technology

With the development of informatization and digitalization, railway communication and signaling technology has been developing towards integration and high efficiency. In terms of communication, many countries and companies have begun to plan and deploy 5G technologies and study the next-generation railway communication system. The EU and Germany, etc. are carrying out application extension research on the existing GSM-R system. In terms of signaling, the EU, Japan, and some manufacturers have successively started research on next-generation train control system and developed new train control systems such as hybrid ERTMS 3 and UTCS. DB, Siemens and other companies actively carry out research on the digital interlocking system to further improve system efficiency. Generally speaking, railway communication and signaling technology mainly presents the following development trends.

As the pace of 5G commercialization accelerates, world major technical powers, represented by the United States, Germany, France, Japan and Korea have accelerated 5G strategy and policy layout by formulating development strategies, releasing 5G spectrum plans, funding the 5G industry, supporting 5G technology trials, and building 5G platforms, to take the leading position in this field. In the railway sector, China is leading the way in the deployment of 5G technology, with full coverage of 5G signals over several stations and high speed lines and active exploration of 5G applications in railway communication. Deutsche Bahn AG (DB), SNCF and other enterprises are also actively applying 5G technologies, such as joint study by DB and Nokia on a 5G-based automated communication system, co-building of 5G Labs by SNCF and Nokia.

The current GSM-R system is based on time division multiplex system, it is impossible to achieve packet-switched data transmission, and there are also shortcomings include small bandwidth, weak interference immunity and insufficient capacity. For this reason, countries are actively developing and expanding GSM-R systems and researching the next-generation railway mobile communications.

The EU is studying the application of IP protocols for GSM-R systems, using GPRS or EGPRS to extend the operational capacity of the GSM network, which is planned to be implemented around 2022. In parallel with the construction of the GSM-R radio network, the German railways have developed, tested and implemented multiple railway-dedicated communication systems meeting communication requirements between railway sections and stations including wireless train dispatching, wireless shunting, general voice service, telephone communication across traffic management sites and wireless communication. GSM-R system greatly simplifies the dedicated service communication equipment. DB has proposed an ultimate application of the GSM-R system in dedicated railway communication, that is, to provide all dedicated railway communication services with GSM-R landline. 

With further development of satellite positioning technology, foreign leading train control suppliers have also launched train control systems or projects applying the satellite positioning technology. The United States, the EU, Japan and China have successively started the research on the application of satellite positioning technology in train control systems. They plan to apply the satellite communication for train positioning and cancel the track-side equipment such as axle counter, track circuit and balise, so as to reduce construction costs and maintenance costs. 

At present, to reduce the overall cost and life cycle cost of train control systems and improve their overall performance, many foreign countries have begun to improve the existing train control systems and develop new train control systems. For example, the EU has begun to develop the next-generation train control system with automatic train protection (ATP), automatic train operation (ATO) and automatic train supervision (ATS) functions. European companies have been engaged in development of the hybrid ERTMS 3-level system to reduce track-side equipment and form virtual fixed block sections. Japan has researched a new train control system (UTCS), which can be completely independent of the track circuits and replace the traditional blocking section and interlocking equipment. From the perspective of technological development, the train control system will be developed towards digitalization, automation and networking in the future. It will gradually take the place of the ground equipment, and improve the track passing capacity and ensure the train operation safety.