CommTel powers comms for Western Sydney Airport rail link

The $11 billion Sydney Metro – Western Sydney Airport project, currently under construction, is a public–private initiative that seeks to transform Western Sydney. The 23 km rail line includes 9.8 km of twin-bore tunnels and 10.6 km of elevated track, connecting six new stations from St Marys to the new Bradfield City Centre via the Western Sydney International (Nancy-Bird Walton) Airport. The project also features 12 new metro trains, core rail systems, and a stabling and maintenance facility at Orchard Hills.

CommTel is deploying cutting-edge solutions for the driverless metro line, providing uninterrupted 4G and 5G mobile connectivity throughout the passenger journey. An advanced fibre-based repeater system, deployed across tunnels and station interiors, supports all frequency bands from 700 MHz to 3.8 GHz and leverages advanced MIMO technology for high-speed connectivity. The system is designed to ensure continuous indoor and outdoor coverage for all mobile carriers along the entire corridor. Key components include radio base stations (eNodeB and GNodeB), central nodes, remote units, hundreds of indoor antennas, and kilometres of radiating cables in tunnels — all seamlessly integrated with existing outdoor networks.

In addition to delivering the public underground mobile network, CommTel plays a key role in providing a private, mission-critical O&M radio network. This system supports essential voice and data communication services and includes radio base stations across outdoor tracks, tunnels, stations and depots, as well as an onboard radio system for 12 new trains and maintenance vehicles. It also features a centralised network management system and dispatch functionality, integrated with the broader Sydney Metro operations.

CommTel worked in close alignment with Sydney Metro and rolling stock manufacturers to ensure the new onboard radio systems deliver cutting-edge performance for both front and rear cabs. These systems should support efficient train, station and depot operations, boosting reliability and safety. CommTel is also extending the NSW Public Safety Network (PSN) into all underground sections of the metro, for uninterrupted emergency services communication; this is achieved through an indoor fibre-based repeater distributed antenna system.

This ambitious development comes with stringent wireless network performance requirements for coverage and capacity, compounded by the complex tunnel environment. Challenges include long-distance RF transmission, confined spaces, reflective surfaces, signal multipath issues, interference from electrical systems, and risks of passive intermodulation (PIM), and voltage standing wave ratio (VSWR) anomalies. CommTel has worked closely with civil and electrical engineering teams from the design phase to mitigate these challenges, strategically placing antenna systems to meet in-train signal threshold expectations while minimising interference, PIM and VSWR problems.

CommTel’s design team says it has successfully delivered on key performance indicators (KPIs) across all the relevant technologies, including TETRA (mission-critical O&M radio), P25 (PSN), and 4G and 5G (public carrier), providing uniform signal coverage by deploying a smart fibre-based repeating distributed antenna system for the 4G/5G network and PSN and distributed base station architecture for TETRA to cover this extensive network of a 20 km tunnel (twin-bore), six stations and one depot with high availability. The company is delivering the project as a turnkey solution — covering the entire spectrum of communications needs, from public and mission-critical networks to 4G/5G carrier-grade systems.

The scope of deployment includes:

• radio base stations;
• a fibre-based repeating system for the PSN and public cellular network;
• radiating cables for tunnel environments;
• outdoor trackside monopoles;
• antenna systems;
• train and maintenance car radio systems; and
• core telecommunications infrastructure.
   

With tunnel boring now complete, the project enters its next major phase: constructing six state-of-the-art metro stations. CommTel says is proud to contribute to this transformative project, helping position Western Sydney as a future global economic powerhouse.

Image caption: Integration staging in the CommTel facility.