"Once a system comes into place, there’s no going back – passengers become quickly expectant..."
What were you doing in 1992? Work? School? College? Maybe you weren’t even born. George H. W. Bush was President of the USA, West Germany were the holders of the World Cup, and in Hong Kong (which still had five years left of being a British colony), the world’s first 900 MHz 2G subway Distributed Antenna System (DAS) came online for Hong Kong MTR Corporation Ltd (MTR). Yes, that’s right, whilst transport networks in many cities are struggling with connectivity, Hong Kong has been offering it for over 25 years. At the heart of this remarkable early adoption of technology is Radio Frequency Engineering (RFE) which has designed, built, installed and maintained communications systems for the MTR for more than 20 years. Part of the BAI Communications family since 2007, today Luke Upton speaks exclusively to Paul Chan, Managing Director of RFE about their work, what it is like to have worked on passenger connectivity in a period of huge change, exporting their knowledge overseas, 5G and much more.
The Hong Kong network is one of the world’s busiest rapid transit railway systems – serving 2.0 billion passengers per year, across ten main commuter lines, 91 stations and 68 Light Rail stops. The average ridership per station is a few times higher than subways in major cities like New York and London.
Paul (pictured below), who worked for the Hong Kong government and Hong Kong Telecom before co-founding RFE in 1997, tells us more about how they began working with MTR and helping deliver connectivity:
“Whilst working for Hong Kong Telecom in 1992, we had regular contacts with MTR so got to know the organisation and its passenger focus. In 1997 MTR invited International contractors to bid to build the Mobile Phone System for then new 1800 MHz spectrum serving six mobile network operators (MNOs). I saw the opportunity, and set up RFE with associates to partner with a German company – Radio Frequency Systems GmbH to offer our services. We won the contract and that began the business and our connection with MTR which is still going strong 21 years later.”
The task given to RFE was how to bring connectivity to a complex and incredibly busy underground network, which uses highly sophisticated precision-engineered systems supporting multi-band, multicarrier services. This is a challenge that RFE have thrived upon, and in delivering this solution have ensured that passengers on the Hong Kong network now expect, and receive constant access to high-speed wireless data on demand, including when they ride underground public transport. As anyone who has travelled on the network in Hong Kong will confirm, its connectivity leads to plenty of travellers watching films or television whilst on their way to work or home.
As in any technological development two decades is a long time, so I am keen to hear from Paul what some of the changes are he has seen in this time; “There’s been a huge advancement in technology in this period, particularly around mobile phones, where have gone from 2G, to 3G, to 4G and now onto 4.5G. And for our next systems we are already looking at future proofing for 5G. In addition to technology, the markets are now more open and as a result competition is much keener. It used to be largely dictated by US and European companies, but is now dominated by Chinese vendors like Huawei and ZTE. Hong Kong’s location and history, makes us as a result the location of a very competitive market.”
5G, the fifth major generation of the standards that encode and transmit data over radio waves, will offer the possibility of providing reliable connections to huge numbers of wireless devices simultaneously, enabling a huge expansion of the “Internet of Things” (IOT). As Paul says, the frequency bands have not yet been agreed, but by the end of 2018, we will see the first real world tests. The Tokyo Olympics in 2020 are also planning to present the full range of what 5G can offer. RFE are “nearly there” with their own technology, so they will be ready when the change arrives.
The incoming 5G change is just one example of keeping pace with changing demand; “As I’ve said Hong Kong is a competitive market, so we are very market driven. We are always alert to upcoming technology changes in the market, and are always working on smarter ways of doing things as well as partnering with other leading technology companies to offer better implementation and lower costs. An example of this would be our work on the MTR West Island Line in 2014.”
RFE was tasked with a new challenge: design a brand new confined coverage solution for its new MTR West Island Line, consisting of three new underground stations with approximately 3km of new tunnels. The DAS network requested by the MTR and the Mobile Network Operators (MNO) was substantially more complex than previously deployed networks. The solution was what is believed to be the world’s first Multiple In Multiple Out (MIMO) LTE development in an underground transit system. RFE worked closely with Hong Kong Telecommunications (HKT) – which operates leading mobile carrier CSL – to design, implement and commission a six band 2G, 3G, and 4G (LTE) subway DAS network
The new DAS network was built with the highest traffic capacity of four to six sectors per station covering over 20 sub-bands from 800 to 2,700 MHz. The network covers the new extension’s stations, tunnels, high speed elevators and public access areas. The result is extremely fast data services of up to aggregate of 5 Gbps per station, the fastest wireless data speeds available worldwide. Individual users, depending on their model of handset, can experience a data rate of up to 600 Mbps.
With London, among those cities currently beginning the process of providing cellular connectivity for its metro passengers, I ask Paul what advice he can offer just beginning this technological journey.
“There is a great difference between cities in their deployment, whilst here in Hong Kong we have had multiple generations of system enhancements and upgrades since the mid-1990s. In New York the first subway connectivity system wasn’t built until 2014, and London is yet to build one. Once a system comes into place, there’s no going back – passengers become quickly expectant. We’ve seen that in Hong Kong, but also in subways in Singapore, Taiwan, Thailand and mainland China where we’ve worked. For those just starting, I’d advise them to keep up to date with all the latest technology and try and ensure that your infrastructure is as ready as possible for the future technology developments. There’s a few basics you can focus on - try to make things fibre-connected with power points and space around then for future expansion or replacement by future models.”
“I’ll finish with another example that relates to keeping pace with changes. We mentioned 5G earlier, but there’s something with them that I am excited by and that’s Active Antennas. They are evolving quickly and for 4.5G and then 5G we are developing versions that can be upgraded but reuse the same fibre infrastructure. It’s like changing a light bulb! As a result it’s easier and more cost effective to make upgrades. It’s an exciting time and we are looking forward to the next set of upgrades and changes.”