RoF for High-Speed Trains

The provision of broadband Internet connections and advanced services to moving users on high-speed trains is gaining a lot of interest owing to the rapid deployment of high-speed railway worldwide and the emergence of broadband services. Nevertheless, high mobility, frequent handover, and diverse transmission environments remain as bottlenecks for a high-speed communication network for high-speed rails. In this chapter, a radio-over-fiber-based linear-cell network using backhaul links in the millimeter-wave band is present to overcome the challenges. Using the system, the radio cells along the railway track can be significantly simplified, rendering the system a cost-effective solution. In addition, by combination with optical switching technology, a moving backhaul network together with the train can be constructed. Thus, a handover-free network over a long coverage area can be realized. The system concept and operating principle of the system are described. The proof-of-concept demonstration in the laboratory was conducted. In addition, a field trial on a high-speed rail system in Japan was also demonstrated.