Interconnection of Remote GSM-R Dispatcher Terminals to a GSM-R Central Hub Across an SDH Transport Network

Global System for Mobile Communications for Railways or GSM-R is a standardized digital system for railway communications and an integral component of railway safety and security operations throughout much of Europe and other parts of the world. Based on GSM mobile technology, GSM-R streamlines many of the existing broadcast communications systems used to transmit signaling, alarms, maintenance, cargo, and passenger data and supports secure voice among various operational, maintenance and emergency teams.

 

This application illustrates how a southern European railway operator deployed RAD’s FCD-E1M network termination unit (NTU) together with the company’s FOM-E1 fiber optic modem and converter to transmit crucial message and alarms as well as mission- critical voice from remote dispatching sites to a central hub. At the central site, they deployed RAD’s Megaplex-4100 multiservice multiplexer.

 

The dispatcher terminals have ISDN BRI and Ethernet interfaces, which are connected to the NTU, and the traffic is multiplexed over the E1 line off of the SDH ADM. The Megaplex-4100 multiplexes/demultiplexes the ISDN and Ethernet to a PBX and server respectively at the CO.

 

RAD's multiservice multiplexing system allows railway communications' planners maximum flexibility in extending their GSM-R backhaul network over SDH copper and fiber access lines.

Although, for railway operators and their GSM-R communications engineers, the focus of their interest lies naturally in the GSM-R radio system, the vital contribution made by the backhaul network to GSM-R availability and performance cannot be overlooked. For this reason, major GSM-R turnkey manufacturers deploy RAD's multiservice access equipment to facilitate transport of mission-critical voice and data between remote dispatching terminals and central control hubs.