Bombardier Transportation has successfully completed tests to operate its range of mass transit and mainline rail control solutions with the latest Long-Term Evolution (LTE) 4G standard for wireless data communications.
The tests were carried out with the four leading mobile telecommunication suppliers – Ericsson, Huawei, Nokia and ZTE. The technical assessments were conducted in line with the rail signalling industry’s Quality of Service (QoS) requirements for the transmission of critical signalling information alongside other wireless communication with the train.
The LTE standard supports high speeds and capacity for wireless data transmission networks and offers the ability to consolidate delivery of multi-service traffic into a single wireless network. Well known for its roll-out on commercial mobile networks, LTE is rapidly being adapted for the railway industry for ground-to-train voice and data communications.
Operators using LTE will be able to integrate the transfer of safety-critical signalling, closed-circuit television, passenger information system (PIS) as well as on-board internet services onto one network. In addition, operating rail control solutions with LTE will enable enhanced system stability and data encryption and security.
Peter Cedervall, President, Rail Control Solutions Division, Bombardier Transportation commented: “Thanks to its high capacity, LTE can provide a broad range of services to the public and various infrastructure operators. It offers an effective, comprehensive and economical solution for city planners and national infrastructure decision makers.
“Our recent, successful multi-service tests with a number of telecommunications networking partners will ensure we continue to offer our customers around the world reliable, proven and advanced solutions as they respond to new requirements.”
Ericsson said it completed a total of 11 tests in a laboratory at simulated speeds of up to 200 kilometres per hour to determine the ability of the LTE networks to support communications-based train control (CBTC) and multiservice solutions. Examples of multiservice solutions are closed-circuit television (CCTV), voice, platform information, advertising and Wi-Fi for passengers.
CBTC uses high-resolution location determination and high-capacity data communications - such as those enabled by LTE networks - to support automatic train protection, operation and supervision functions. With more accurate information about the exact positions of trains, operators can manage traffic in a more efficient and safe manner.
CBTC systems are more reliable than older train control systems, require less wayside equipment, have built-in redundancy features, and enable operators to make optimal use of tracks and trains by responding to demand more swiftly and efficiently.
In the CBTC tests, the LTE networks achieved uplink and downlink latencies far below the threshold of 100 milliseconds and packet losses approaching zero (anything less than 0.5% was considered a pass mark). Quality of Service capabilities built into Ericsson's equipment also allowed for the preemption and prioritization of mission-critical railway services.
Charlotta Sund, Head of Customer Group Industry & Society at Ericsson, said: "The results of the tests performed to date are very promising and we will continue to test a variety of modems to ensure we can provide robust LTE networks for rail applications. We aim to develop solutions that ensure enhanced rail safety through communications-based train control and CCTV, as well as enhanced entertainment for passengers through services such as voice, platform information, advertising and Wi-Fi."
ZTE said it has also completed similar a joint test of Bombardier Transportation’s communications-based train control with ZTE's LTE solution for the railway industry. It added that the success of this test is an important step towards wide commercial use of LTE rail transit systems.
The joint test measured LTE systems’ key performance indicators (KPIs) when carrying diverse services such as CBTC, closed circuit television (CCTV), passenger information system (PIS) and Wi-Fi, simulated for trains running at medium and high-speeds.
ZTE said that its LTE solution for the railway industry has unique technical features. As the target areas are covered by two integrated networks, the LTE technology is a highly reliable solution for high-speed rail operations. Moreover, the specially designed redundancy system for core devices greatly reduces the possibility of any single point of failure.
This allows the system to not only guarantee great reliability, but also offers a better user experience. Compared with traditional narrowband wireless systems, the LTE rail transit system uses a bearer network over LTE, which provides high bandwidth and transmits CBTC, CCTV and PIS services over the same network. This enables users to enjoy multiple services.