In-tunnel wireless coverage: RFS brings coverage efficiency to the next frontier

Colombes (France), February 11, 2010 – On the occasion of the 2010 Mobile World Congress, Radio Frequency Systems (RFS), the global wireless and broadcast infrastructure specialist, highlights its technology and market leadership in in-tunnel wireless coverage, arguably one of the world’s most challenging environments from a radio frequency (RF) perspective, with significant successes in China and Europe.

In China, where RFS dominates with 80 percent of the in-tunnel wireless coverage market using radiating cable technology, recent successes with China's prestigious Ningbo-Taizhou-Wenzhou Railway (also known as the Yong-Tai-Wen railway) and Line 3 of the Shenzhen Metro, are helping to ensure safety and enhancing communications for travelers.

Delivering seamless GSM-R coverage in tunnels along the Yong-Tai-Wen railway

With trains traveling at speeds of up to 200 km/h (124.2 mi/h), safety is a critical concern for the Yong-Tai-Wen railway. RFS is supplying 106 km (64.8 mi) of RADIAFLEX® radiating cable, along with heavy-duty clamps, DC blocks, surge arresters and connectors, to enable wireless network coverage within the tunnels along the entire length of the 260-km (161.6-mi) railway. This seamless Global System for Mobile communications-Railway (GSM-R) coverage allows railway staff, along with engineers and emergency personnel, to maintain voice contact at all times and to exchange text messages and basic mobile data.  

The technical problems facing engineers installing in-tunnel wireless communications technology are considerable. Along with the often hot, dusty and rugged tunnel environment, the twists, turns and constrained tunnel cross sections, coupled with large and fast-moving vehicles, present an onerous RF distribution challenge. The low weight and small minimum bend radius of RFS’ RADIAFLEX radiating cable expedite installation in locations with restricted access.

On the Yong-Tai-Wen railway, high train speeds create severe turbulence in the tunnels. RFS is meeting the challenge with heavy-duty clamps that can withstand turbulence from trains traveling at speeds up to 300 km/h (186.4 mi/h) and higher. This means that, as train speeds are increased, the Yong-Tai-Wen railway can be assured the in-tunnel wireless coverage system will be able to handle the hurricane-like wind forces.

Ensuring high-quality reception along Shenzhen Metro Line 3 and its 22 stations
For the three-year Shenzhen Metro Line 3 project, RFS is providing in-tunnel RF commercial, Terrestrial Trunked Radio (TETRA) and security wireless communications sub-systems along the entire 32 km (19.9 mi) of Line 3 and its 22 stations. The results will ensure that wireless communications are available to Shenzhen metro personnel, passengers, police, rescue workers and fire brigades at all times.

With diverse stations, including six subway sites, one half-subway site and 15 light rail stations and cramped working conditions, the Shenzhen Metro Line 3 project is challenging from an RF perspective. The distances between TETRA base stations and radiating cables also make for some interesting challenges, especially when signal propagation is involved. Again, RFS is proving it has the right combination of know-how and technology to meet the demands.

In-depth understanding of the way wireless signals propagate and interact with other RF signals in subway tunnels allow RFS engineering staff to plot exactly where the base stations and RFS RADIAFLEX radiating cables were needed. This accuracy is achieved without the need for major on-site tweaking which, given the cramped conditions in the tunnels, would be difficult.

Along with its proven technology, RFS’ reputation for supplying high quality and reliable wireless transmission systems in and on subways and light rail systems, while remaining on schedule and within budget, were deciding factors in its selection for the Shenzhen Metro Line 3 project.

Focusing on technology excellence to set the standard for mission-critical in-tunnel wireless communications worldwide
RFS’ in-tunnel expertise and leadership are also recognized in Europe, where its in-tunnel RF coverage technology is being used to provide mission-critical wireless coverage in two high-profile deployments.
    
At 24.5 km (15.2 mi) long, the Laerdal road tunnel in western Norway is the world’s longest road tunnel. Reliable wireless coverage is essential for emergency and personnel communications, accident prevention and fire safety. With RFS’ proven in-tunnel wireless technology, travelers, workers and public safety authorities can be assured of access to wireless communications when they need it most.

In the United Kingdom, RFS’ RADIAFLEX radiating cables, CELLFLEX coaxial feeder cables and accessories form a key component of the wireless communications system in the three tunnels along the channel tunnel rail link (CTRL Section 2). From a technology perspective, the low longitudinal and coupling losses of RFS’ RADIAFLEX radiating cable were key factors in its selection for the tunnels, which have a combined length of 21 km (13 mi). RFS’ ability to provide heavy-duty radiating cable clamps that could withstand the forces generated by trains passing at 250 km/h (155.3 mi/h), and to concurrently support all four tunnel communications systems, were also important factors in its selection.
 
“Leveraging its successes in China and its strong European presence, RFS is the leading provider of RF coverage systems for the critical multi-carrier and multi-service applications in road and rail tunnels worldwide”, says Patrick Houze de l’Aulnoit, VP Global Sales & Marketing at RFS.

RFS provides today’s most advanced active, passive and hybrid RF distribution systems for in-building and in-tunnel environments. Its premium range of best-in-class solutions, which include the broadest range of RADIAFLEX radiating cables with superior performance, the ClearFill® fiber-optic extension and distributed antenna suite, plus unrivalled point of interface technology, are expertly scaled to match every indoor coverage need for 2G, 3G, 4G, TETRA and GSM-R in the 800, 850, 900, 1700, 1800, 1900 and 2100MHz bands.


During the RFS StayConnected Days @ 2010 Mobile World Congress, RFS is hosting a Press Briefing on Wednesday, February 17 from 9:00 am to 11:00 am at the RFS booth (Hall 2, Booth C53). To confirm your participation at the RFS Press Briefing or schedule an interview with an RFS executive, please contact:

Eric Giaretto,
eric.giaretto@rfsworld.com,
+33 (0)6 80 26 42 40.

Trademarks: Radio Frequency Systems®, RFS®, RADIAFLEX® and ClearFill® are registered trademarks of Radio Frequency Systems. All other trademarks are the property of their respective owners.

About RFS
Radio Frequency Systems (RFS) is a global designer and manufacturer of cable, antenna and tower systems, plus active and passive RF conditioning modules, providing total-package solutions for wireless infrastructure.

RFS serves OEMs, distributors, system integrators, operators and installers in the broadcast, wireless communications, land-mobile and microwave market sectors. As an ISO compliant organization with manufacturing and customer service facilities that span the globe, RFS offers cutting-edge engineering capabilities, superior field support and innovative product design. RFS is a leader in wireless infrastructure.