With technology provided by Sequans Communications and Nokia, the RATP (Régie Autonome des Transports Parisiens), the state-owned public transport operator in Paris, successfully trialed a 4G LTE network automated on Line 14 of the Paris Metro. In this world-first experiment, A 4G LTE system was installed on one of the trains, using base station equipment from Nokia and a Sequans-powered LTE modem, to run all of its operational communications systems in the very challenging underground metro environment. The metro communications systems today require a complex combination of Wi-Fi, digital radio, and 3G/4G wireless technology, and this trial was conducted to demonstrate the highly promising benefits of a unified ground-to-train radio network based on 4G LTE technology. The trial was completed as part of the SYSTUF (SYStéme Télécom pour les Transports Urbains du Futur) project.
The trial showed conclusively that a 4G LTE system is capable of processing data for CBTC (communications-based train control), CCTV, radio, passenger information, and maintenance monitoring services all at one time. The RATP now has a proven alternative to proprietary Wi-Fi, which has serious limitations in that Wi-Fi is not optimized for mission critical applications and is not capable of carrying both safety-critical and non-critical information, nor distinguishing between the two. 4G LTE, which is a much more advanced technology, has primary characteristics that include high speed, security and capacity, with the ability to carry voice and data for train control, onboard video surveillance and passenger information, simultaneously, on a single IP network.
Sequans is one of the world’s leading providers of LTE semiconductor solutions and during the trial worked closely with Nokia, manager of the SYSTUF project. The network architecture for the trial consisted of radio head transceivers spread over the tunnel and stations of line 14 along the covered area, provided by Nokia, and on board equipment, which included an on-board mobile router with an LTE modem provided by Sequans. Sequans delivered advanced capabilities, enabling the system to operate at speeds up to 80 km/h with efficient handoffs between small cells in a real-world underground train environment. The technical achievements also included overcoming the mask effect from other trains. Sequans also provided the required monitoring tools to measure the performance of the LTE device inside the train. Sequans’ LTE chips are available in multiple LTE band formats, as required by public transportation systems around the world.
See Sequans and Nokia engineers at work in the following video: