BAI Communications has delivered wireless communications in some of the most extensive rail networks in the world. These are the five challenges, and lessons, that BAI faced when deploying underground communications networks in New York, Toronto and Hong Kong.

1 – Dealing with dust

Underground railways are hostile environments. Heat, humidity, and poor air quality should be factored in the planning stages of any underground communications project.

Brake dust released by friction between brake pads, wheels and rails is a major contributor to poor air quality. Steel based, it’s pervasive, conductive, and a significant threat to smooth running sensitive telecoms electronics.

Dust in the environment

Addressing the issue requires using enclosures designed to keep dust out, to avoid equipment failure and fire hazards. Given the safety implications, and the unique characteristics of each underground environment, it may be necessary to create a new design from scratch. While this can take time, it’s worthwhile to source a solution that is discreet, vandal and graffiti resistant and, most important of all, future-proof and reliable.

2 – Completing complex projects without disrupting passengers

Many cities operate metro rail services that stop for just a few hours a night, with some even running 24/7. Popular with passengers, this almost constant service presents authorities with a challenge – how to conduct essential maintenance, or integrate new technologies, without disrupting timetables.

Getting this right relies on flexibility and preparation. Work must be scheduled during breaks in service – at weekends or overnight. Work scheduled in one location can also be postponed at the last minute. In such situations, contingency plans help teams relocate to other sites quickly.

Ability to innovate is also incredibly important. During work on Hong Kong’s metro communications network, tunnel size presented challenges that had the potential to delay completion. Safety requirements prohibited the use of conventional ladders, requiring scaffolding instead – considerably more time-consuming to set up and move. To avoid delay, BAI sourced a new platform ladder. It was lightweight, easy to transport, and, most importantly, saved at least 30 percent of the time needed in traditional scaffolding.

Passenger Experience

3 – Mind the gap – underground communications are installed in confined spaces

Delivering high-speed wireless connectivity requires suitable places to install sensitive electrical equipment. Finding them is more difficult in underground tunnels where ceilings are often low and space is at a premium. Any location needs three key features: interference-free communications coverage, protection for equipment against damage, and ability to restrict unauthorised access.

Ultimately, finding the perfect placements requires highly detailed planning, including surveying equipment locations in every station and tunnel to ensure compliance with requirements. Again, technology can play a huge part in this process. In Hong Kong, laser-based measurements across sites guaranteed that trains did not strike the newly installed equipment.

Confined spaces

Meanwhile, in New York’s subway, BAI used 3D visualisation, similar to Google’s Street View application, to speed up the entire planning process. Station planners could visualise the installations and the best locations for equipment. All while we carefully maintained the right aesthetics. While this approach provided a highly accurate way of demonstrating compliance, it also saved the time, hassle and expense of frequent site visits.

4 – Developing subterranean skill sets

Finding employees with the right skills is central to success in many industries. It is particularly relevant when it comes to underground connectivity given the numerous regulations governing which installation engineers can work on site. The contractors in electrical and mechanical installations were highly professional and experienced.  However, they often needed to acquire new skills when it came to telecom infrastructure deployment.

For example, coax cable and fibre used for high-speed wireless services require careful handling and precision fitting to avoid performance degradation. Even the smallest errors, like a kink in the cable, can seriously impact user experience. As a result, finding contractors qualified for underground rail work who also possess requisite skills for installing next generation mobile communications networks is challenging.

Develop Skills

The team responsible for the Wi-Fi roll-out and mobile coverage across the New York subway faced a challenge in this regard. Their deadline was two years. Meeting the new deadline required a doubling of the contractor workforce. The majority of new hires had limited experience working with fibre.

To meet the completion deadline without compromising quality, BAI had to restructure installation teams. A highly experienced lead who directed contractor engineers with less experience in telecom cable installation was onboarded. By structuring the team creatively, it was possible to complete the job within the challenging time frame and to the high standard required.

5 – Aligning transport and telecom business models

Both the inter-city and the metro railways require huge infrastructure investments. Rail systems remain in service for decades. Train purchases are typically on a 30-year cycle. However, the telecom industry is fast-paced. It is driven by an ever-accelerating rate of technology development and short system life cycles.

In terms of structure, rail authorities tend to be monolithic, taking on most of the responsibility for infrastructure and operations. Meanwhile, partnerships formed by stakeholders with different specialisations are the foundation of the telecom industry.

Marrying these philosophies requires a change in approach. Firstly, developing relationships between key personnel at the transport authority and the telco provider is essential to streamline processes. Secondly, doing so can help to ensure quick and easy access to trackside areas. Moreover, this allows partners to work with the flexibility and efficiency required for next generation telecom deployment.

This was also central to the success of the preponed New York subway installation. Therefore, taking the time to forge true partnerships between competing companies in the early stages ensured effective coordination, ultimately saving time. Being able to pull all parties together to agree a solution was a key part of the process and its success.

The importance of experience and innovation to underground communications

Every underground system presents a unique environment. Consequently, service providers must tailor every communications solution to be able to address different challenges. There is no such thing as an off-the-shelf solution.

As these five examples show, BAI has always planned ahead extensively and innovated in the face of unexpected challenges. Taking this kind of engineering approach to problem-solving ensures high quality services, reliability and long-term future use.