Mine operators are discovering that robust digital underground communications systems are vital to meeting production demands. Designers and engineers of modern mines will tell you that merely meeting the minimum compliance standards for workplace safety regarding underground communication is a missed opportunity. Updated mine communication systems can go beyond compliance by improving operations data and real-time production status resulting in greater production efficiency, improved machine learning datasets, and even more robust safety.

No two mines are the same and communications systems need to be tailored to these differences. Providers of one-size-fits-all underground communication solutions may not be able to deliver on every capability within the system. Studies of the physical characteristics of underground mines reveal the impact on which communication systems will be used for underground mining. Moreover, the difference between excavation styles (room and pillar, longwall, stope, etc.) is a major consideration in both the installation of the communication infrastructure and the behavior of radio transmissions inside mine galleries. *

A customized communication system tailored specifically to the needs of the underground environment improves coordination and helps make operations more adaptive to sudden changes in production or safety.

"Improving the data collected within the mine influences several production factors when it comes to reporting, alerting, and workflows," said Rob Albinger, General Manager of StrataConnect, Strata Worldwide. "Where we've seen significant improvements is in data collection. If data sets are correctly aggregated, they inform machine learning software which can then be used to advance operational efficiency and safely increase production."

Production data can now be collected from multiple sources including machinery, automated systems, conveyors, proximity sensors, dust detectors, etc. This data can be aggregated and leveraged to reveal inefficiencies in production. 

Reliable Underground Communications

"Unclear or staticky communications reduce efficiency and safety," said Albinger. "Clear and consistent connections ensure that sections and workfaces are coordinated, and instructions are understood. Well-engineered and designed underground communication networks anticipate safety issues and expand with the mine."

From corrosive gases to gritty fine dust, the punishing mining environment can quickly render common consumer equipment useless. This also applies to cables, relays, terminals, couplers, dividers, converters, etc. A breakdown in the constituents of the network can result in lost communication across the network, creating a risk exposure. High-quality equipment and underground mobile devices are easier to maintain, experience significantly less downtime due to equipment failure, retain more reliable connections, and provide a longer equipment life.

Customizable Mine Communication Networks

StrataConnect mining communication solutions are a customizable variety of wired and wireless technologies that combine functionality, redundancy, and economics to produce seamless underground networks.

StrataConnect Wireless is a wireless battery-powered mesh network of nodes that interconnect and interface with a centralized communications hub, creating a complete personnel tracking and communication system. This wireless system provides a real-time awareness of underground operations and working conditions. The nodes are strategically hung from the mine roof and communicate with each other to form a redundant relay network that pulls data and comms from the depths of the mine to the surface instantly.

Handheld, rugged, and easy to read display devices, provide individual miners with a personal connection and tracker. A digital mine map tracks the movement of these devices, displaying their whereabouts and direction of travel underground in real time.

The StrataConnect Server and Graphical User Interface (GUI) are at the heart of Strata's communication system. These facilitate communication between surface and underground operations. From text messages to gas detection alerts, StrataConnect consolidates communication and control into a central platform that is user friendly to monitor and manage.

StrataConnect DigitalBRIDGE is an underground network solution that is designed to be added to an existing fiber network. It provides the speeds and capabilities of fiber with the additional benefit of delivering power to connected devices placed anywhere along the network. The technology:

• Extends fiber to expand digital connection into active working sections or the "last mile"

• Carries power and data in single cable

• Simplifies network installation for reaching all areas of the mine

For integration into existing fiber networks, the DigitalBRIDGE Portal is installed nearby any fiber switch and power station to bridge high speed data over to coaxial cable and insert DC power. Then, personnel can tap into DigitalBRIDGE coax at any point to install Ethernet devices or split the network into multiple directions. The DigitalBRIDGE Quadport2 enables Power-over-Ethernet (PoE) connection of up to four devices, such as Wi-Fi access points, tracking systems, IoT processes, cameras and Programmable Logic Controller (PLC) units.

StrataConnect DigitalBRIDGE Plus+ digitizes leaky feeder systems to integrate technologies for high-speed PoE connectivity, without affecting VHF radio frequencies. Ethernet can be inserted at the head end to run throughout the underground network as long as DigitalBRIDGE Plus+ line amplifiers are used, or it can be integrated underground by bridging digital data from existing fiber networks onto the leaky feeder cable. This connection is created via a DigitalBRIDGE Plus+ line amplifier with Ethernet. Ethernet end-point devices can then be installed anywhere, receiving power and data connection through DigitalBRIDGE Plus+ Quadport2. DigitalBRIDGE Plus+ line amplifiers are required to transverse the digital signals where Ethernet access is needed, but in areas where no Ethernet access is required, operations can continue to use existing line amps.

DigitalBRIDGE Plus+ also supports both Digital Mobile Radio (DMR) and Land Mobile Radio (LMR) solutions for underground operations.

Mines Require Modern Communication Solutions

StrataConnect networks provide a signal and digital pathway for devices such as sensors to connect, upload real-time data, and be controlled remotely. It is important to have high bandwidth to enable large amounts of data to be carried through the system at once. Being connected to devices for monitoring, data, and alerts vastly improves workplace safety and could provide staff with the valuable seconds needed to react to accidents or seek shelter.

The expectations of investors and the demand for mineral commodities have put pressure on mine operators to run lean and efficient outputs with more precise and up-to-date reporting. With StrataConnect options, Strata Worldwide offers high quality mining communication systems. Every mine is unique, so we customize sophisticated solutions for optimum operations, improved safety, and greater production efficiency.

*Published in: IEEE Communications Surveys & Tutorials ( Volume: 11, Issue: 3, 3rd Quarter 2009)