Jaime Laguna discusses keeping underground mines connected with private wireless
From a miner’s perspective, there are obvious differences between open-pit and underground mining. Surface mines consist of large, cone-shaped excavations in which workers, vehicles and machinery can move around. Underground environments feature thick rock walls, confined spaces and a continuously increasing network of tunnels and galleries in which operations take place in almost “blind” conditions.
Connectivity is a critical asset in both types of environments. Fast, reliable data transfer is vitally important for enabling digital automation and ensuring workers’ health and safety in areas with limited visibility for people and systems. But below-ground operations present some unique challenges to the mine’s communication network.
Complex and continuously changing layouts and signal reflection from underground machinery make it difficult to plan, design and deploy mine networks. Geological, geotechnical and operational factors such as extraction sequence, optimisation restrictions and requirements make ubiquitous connectivity essential. Different teams may operate in different sections of a mine simultaneously or move between areas from week to week. As more automated processes come online, they need to be enabled even when workers aren’t present.
What this means is that connectivity must be everywhere. Furthermore, the communications infrastructure needs to support a wide range of new digital applications, such as underground location, ventilation management, and water inrush and methane gas monitoring.
The challenge is to deliver flexible and reliable wireless data and voice communication across a continuously changing geography in a variety of harsh production environments – around corners, despite possible interference – so that automated processes and equipment can function seamlessly and workers stay connected. It’s a tall order for any network.
Wi-Fi has limitations, even in opencast mining. For example, Wi-Fi access points have limited reach and blasts can impair their configurations, which makes them unsuitable for continuous operations. Wi-Fi networks also lack the quality-of-service features required to prioritise critical network traffic. Moving underground creates even greater challenges because Wi-Fi signals can be weakened and distorted by the structure of the mine itself. This creates the need for a high density of access points. In the ultra-connected mine, there can be no tolerance for patchy coverage.
To ensure always-on, everywhere coverage, mining operators may need a combination of radio technologies that includes small cells, micro remote radio heads (RRHs), distributed antenna systems (DASs) and radiating cables (also known as leaky feeders). Network architecture design and radio planning play central roles in successful implementation.
Industrial-grade private 4.9G/LTE or 5G networks meet the need for reliable and secure voice, data and video communications and automated applications in underground mines with low latency and high-speed data transfer.
Although coverage of a single antenna is often limited to a section or a gallery, the power of the cellular signal makes it a convenient choice for supporting caving, room-and-pillar and longwall mining methods as well as in-mine mission-critical and emergency voice and video communications.
Private wireless networks based on 4G/LTE and 5G cellular standards can support all mining applications on a single industrial-grade infrastructure. In addition, they can provide seamless handovers and mobility at high speeds with predictable quality of service (QoS) and support a massive number of active device connections per access point with far greater reliability and security than other network technologies.
A private wireless network can meet the needs of virtually any underground application that requires wireless connectivity, including autonomous vehicles, robotic processes and smart sensors. It can also support applications that are typically served by a cabled connection, such as HDTV camera feeds. LTE and 5G technologies make this possible because they can deliver high bandwidth and reliability, support low-power sensor and IoT networks, and adapt to older network protocols for legacy applications. If wireless spectrum is available, the same network technology can be deployed on the surface and underground to provide fleet connectivity and person-to-person or group communications across the entire mine.
Putting Private Wireless To Work
In 2021, Nokia announced that it would work with mobile operator Telia and implementation partner Digita to build a 5G standalone private wireless underground network in Agnico Eagle’s Kittilä mine in northern Finland. The mining operator successfully completed its first underground 5G video call in June 2022. Tommi Kankkunen, general manager of the mine, looked forward
to more achievements with 5G, saying, “5G will increase the performance of our networks above and below ground, which will enable our digitalised and automated operations to work even more efficiently. With this modern technology, we will be able to continue improving work health and safety as well as reliability.”
The question of which connectivity technology to use in underground mines has finally become a non-issue. With private wireless, mining companies can achieve a big reduction in operating costs and a huge increase in operational gains from a wide range of Industry 4.0 digitalisation and automation use cases.
Jaime Laguna is head of Nokia's mining and oil & gas business