Throughout the world, many railways use the interoperable radio communications network, GSM-R (Global System for Mobile Communications – Rail), for operational voice communications and to provide the data bearer for ETCS (European Train Control System). Within the European Union, and for all infrastructure managers wishing to adhere to European standards such as ERTMS, this is legally mandated via Technical Specifications for Interoperability (TSI).

GSM-R is a technology system based around standardised commercial GSM (Global System for Mobile Communications) equipment (also known as 2G) used worldwide but enhanced to deliver specific ‘R’ (railway) functionality. GSM-R technology is very reliable and has been suitable for serving the railway’s needs over the past decade. However, network demands, coupled with new efficiency requirements and the fact that the GSM technology is not going to be around forever, is driving a need for the next radio technology to serve the railway.

In this context, the International Union of Railways Union (UIC – Union Internationale des Chemins de fer) decided, in 2012, to set up the Future Railway Mobile Communications System project (FRMCS) to prepare the necessary steps towards the introduction of a successor for GSM-R.

As well as being a major player in the provision of 2G, 3G, 4G-LTE and 5G equipment used by all mobile network operators globally, Nokia is also a leading supplier of GSM-R. So, it’s no surprise that the company is a leading participant in the definition of this new standard, which it believes will initially be based on the Long Term Evolution (LTE) telecommunications technology.

Safe hands

Nokia was a pioneer in the GSM-R field, being the first company world-wide to contract a commercial GSM-R project in Sweden for Banverket (now Trafikverket) in 1998, commencing operations in 2000. Since then, the company has deployed over 29 GSM-R networks worldwide, from a full ‘turnkey’ deployment (design, radio planning and deployment) through to end-to-end GSM-R network operations as a full managed service – such as the ADIF high speed railway GSM-R system in Spain and the Prorail GSM-R system in Belgium.

To assure interoperability with other vendors GSM-R, Nokia’s GSM-R system has been developed according to the relevant open standards (EIRENE, MORANE and ETSI). Extensive interoperability tests have been performed to verify network-to-network interoperability including full certified interoperability with the Kapsch GSM-R core. This proven and deployed interoperability enables a step-by-step network-wide transformation to a digital platform.

4G, 5G and the railway industry

Railway operators of all types typically run a mix of narrowband and broadband communications technologies to support their safety-critical, safety-related and passenger services. GSM-R is the most widely adopted radio technology for mission-critical voice and train control data. These services typically require low bandwidth, low latency and high availability, which suits GSM-R well.

However, as new requirements emerge, for example to facilitate automatic train operation (ATO), with more video streams from and to the train, a narrow-band technology such as GSM-R will struggle to support these applications.

Migrating to LTE (Long Term Evolution, 4G and 5G) technology has the potential to support broadband services and high-speed mobility, and also to consolidate all communications needs onto one single, highly flexible but secure and resilient network. Furthermore, the high throughput and low latency performance and stringent Quality of Service (QoS) characteristics of LTE will enable the railways to deliver better services for passengers whilst reducing operational costs.

Nokia has been innovating in LTE for 19 years with many world firsts, and is currently the global number one supplier of commercial LTE equipment with its LTE 4.5G Pro, 4.9G and 5G offerings, all of which have the potential to revolutionise communications, including how public safety is ensured and how industrial processes are run.

Technology choice?

Close to 800 operators are investing in LTE in more than 200 countries serving commercial, private and public safety networks. By 2020, LTE is expected to connect more subscribers than any other mobile technology. It can be served on licensed and unlicensed spectrum and continuously evolves via the standardised 3GPP (3rd Generation Partnership Project) governing body. A Nokia LTE network will support 5G and is designed for evolution over the coming decades.

As a well-established technology that is supported by a solid and growing ecosystem, LTE has a long future ahead of it. Even when the much-vaunted 5G technologies start to be deployed, LTE will provide a long-term foundation for 5G networks.

Technology migration is not trivial and takes time. However, the sooner the capabilities of LTE are brought into operations, the sooner rewards will be reaped in terms of lower operational costs and new revenue opportunities from passenger services. One of the ways these benefits can be realised is through a Private LTE network (PLTE). This simply means the railway having access to an LTE network that only services railway users.

A Private LTE network can support both human and machine communications on a single, reliable network that offers mobility without cumbersome portable radios and opens up the world of the Internet of Things (IoT). Complementing Ethernet and Wi-Fi, Private LTE will help to enable digital transformation in many industries and pave the way towards the adoption of even more capable 5G mobile technologies.

Future

Nokia, which leads the way in 4G LTE technology with a clear and software-driven path to 5G, leverages its AirScale product for the building of a smooth evolution path to 5G with 4.5G Pro and 4.9G evolution of the 4G standard. The evolution from 4G to 4.5G to 4.9G and 5G is tightly controlled by Nokia and adheres to the global 3GPP set of standards that all telecom vendors follow.

5G will initially be made available through evolution in LTE technologies. It will be followed, later in the evolution of the standards, by the introduction of a new air interface that will be backward compatible with the LTE interfaces, the transport function and the core function.

It is likely that 5G-ready devices will start to become available from early 2019, fast tracking to an era where the internet starts to migrate from a communication platform primarily for people, into a platform allowing devices and assets to connect. Going further, it will give consumers the ability to download a UHD movie to their smartphones in a few seconds. 5G will enable offices, cars, trains and assets to seamlessly connect to each other and the cloud.

In terms of track-to-train broadband, this is something that Network Rail Telecom has been investigating. Nokia’s Bell Labs R&D team has already developed the software algorithms required to deliver 10Gbit/s to a moving train at up to 500km/h using mmWave 5G radio, and the company is currently planning trials on a railway test track within the next 12 to 18 months. (NOTE: 5G radio is not the same as 802.11ad mmWave WiFi standards-based radio.)

If you think about the evolution of 4G, an example of achievable speeds is roughly as follows:

4G – 300Mbps

4.5G – 1Gbps

4.9G – 3Gbps

5G – over 10Gbps

The key point to take away is that the different ‘G’s above are all supported by the same Nokia LTE core, which also supports the full Nokia Wi-Fi portfolio, the GSM-R over LTE transformation and the 3GPP 5G mmWave being developed.

An investment now in an LTE core will serve the future of Digital Railway for many years to come and it is this key point that removes the risk to rail – the migration path can be steady and controlled with a very clear 20-year-plus roadmap.

The other key points are the term LTE (Long Term Evolution) which is ‘what it says on the tin’, and 4G/5G is a standard specified by the 3GPP for use all over the world.

The mantra of the moment is “build it once and build it right” for the railway’s future telecommunications infrastructure.

Autonomous vehicles

Much is being reported that the latency performance of 5G is required for autonomous vehicles. However, in Australia, since commencing trial operations in 2008, trucks fitted with autonomous vehicle technology, communicating via 4G LTE, have already moved more than one billion tonnes of material.

In 2017, Rio Tinto’s autonomous fleet accounted for about a quarter of the total material moved in the Pilbara mines. On average, each autonomous truck was estimated to have operated about 700 hours more than a conventional haul truck during 2017, with around 15 per cent lower load and haul unit costs. There have been zero injuries attributed to autonomous haul trucks since deployment, highlighting their significant safety advantages.

Norwegian airport operator Avinor is developing autonomous snowploughs with the aim of increasing efficiency and reducing delays at airports. In March 2018, these autonomous vehicles were tested for the first time at a snowy airport 200km north of Oslo.

Autonomous vehicle technology for rail is already being planned on routes around the world. Rio Tinto is also developing fully autonomous, heavy-haul, long-distance trains for transporting iron ore (see News in this issue) and, in the Netherlands, Prorail has announced it is also planning to trial automated operating freight trains. The CEO of German operator Deutsche Bahn, Rüdiger Grube, has publicly stated the objective of DB is to introduce driverless trains by 2021.

Massive MIMO

Massive MIMO (multiple-input and multiple-output) is used in many radio technologies and, in fact, was invented by Nokia’s Bell Labs in America. A basic antenna will have both a transmit and a receive element, and data is transmitted and received via these elements. It follows that, if you employ more antennas, you can transmit and receive more data.

In Massive MIMO, Nokia does just that, using 64 transmit and 64 receive antennas packed into an array to boost capacity and coverage. Massive MIMO is often seen as a future technology to support 5G networks, but Nokia is making it available for deployment within LTE now. Using existing spectrum and base station sites, the Nokia AirScale Massive MIMO adaptive antenna delivers far more capacity than conventional antennas and radios and can be used as part of the railway to deliver secure, guaranteed data streams.

Massive MIMO antennas are capable of handling very large amounts of data. The processing of this data is therefore intensive, requiring a paradigm shift in processing power at the base-station (where the data from the distributed radios is processed). The Nokia answer is the new “ReefShark” chipset contained within the Airscale base-station platform. Made entirely in-house, this bespoke silicon packs more functionality into 50 percent smaller hardware compared to products that use discrete components; it decreases mMIMO antenna size by half; cuts energy use by 85 percent and boosts the intelligence and performance of MIMO antenna, all based on 3GPP 5G New Radio specifications.

Massive MIMO technology is one of the key enablers to deliver the step-change in mobile broadband performance.

UK first deployment of 5G

Nokia has products to deliver a number of wireless and fixed telecoms technologies now, including Wi-Fi and 4G LTE, and is at the forefront of 5G development.

BT and Nokia recently demonstrated the first UK public deployment of 5G. People in Bristol experienced the next generation of wireless technology in a public urban environment. This included spectacular 3D-like projections, a virtual reality dance piece, and a guided tour on which people walked through time.

The public part of the trial only lasted two days, but the trial continues to include Nokia’s Massive MIMO radio access solutions, network slicing (splitting a single physical network into multiple virtual networks) and edge computing nodes functionalities.

Cormac Whelan, CEO of Nokia in the UK and Ireland, said: “As 5G comes ever-closer to commercial reality, the opportunity to contribute to a ‘real world’ test of the technology in Bristol is invaluable. With the UK’s exciting ambition of becoming one of the first European markets to launch 5G, Nokia is thrilled to be working with the University of Bristol and with BT to make this public demonstration happen and to evaluate how the technology will work in a smart city such as Bristol.”

Nokia are therefore ideally placed to guide the rail industry on the roadmap to what is possible for the future of train radio.


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