The mining industry faces significant communications challenges that can affect mine safety and asset management. With both aboveground and underground mining, physical obstructions such as machinery and terrain can disrupt wireless paths and cause reflectivity, multi-path, absorption, and phasing. Multi-polarized antennas that reduce signal degradation and support consistent voice, data, and video communications are an important part of the solution.
In this white paper from MP Antenna, you’ll learn how multi-polarized antennas for mining operations support mine safety, equipment monitoring, and consistent communications in difficult, dangerous environments with falling rock, clouds of dust and gas, electromagnetic interference (EMI), and line-of-sight (LOS) obstructions.
How Antennas Support Mine Safety
In the United States, the federal Mine Safety and Health Administration (MSHA) establishes standards for personal emergency devices (PEDs) that support one-way communications between underground and surface personnel. MSHA also sets standards for radio frequency identification systems (RFID) that allow surface personnel to track the location of miners. Both technologies are required under the 2009 MINER Act, which was passed in the aftermath of the fatal January 2, 2006 mine disaster in Sago, West Virginia.
PED systems use an antenna loop to radiate signals to miners, who then receive communications as text messages on belt-wearable receiving units. The transmitting antenna can be installed either aboveground or underground, but many mine operators use underground antennas to minimize transmission problems caused by terrain. To promote miner safety, however, these underground antenna deployments need to avoid “shadow zones”, areas within the antenna radius coverage where a message may not be received.
RFID tracking systems also support mine safety. Each miner wears a transmitter that sends out a unique, pulsed signal that’s received by an RFID reader. By installing stationary RFID readers at the various levels of a mine, operators can locate miners who are working underground at depths of several thousand feet. RFID systems are available for ultra-high frequencies (UHF), but mine operators need to choose UHF RFID antennas that can withstand EMI from radios, metal surfaces, and machinery.
How Mining Antennas Support Asset Management
The machines used in mining are a major investment. Equipment maintenance costs also represent a significant part of a mine’s budget. For mines that run continuously, downtime can disrupt production schedules and hurt the bottom line. That’s why mining companies use asset monitoring and management systems with trucks, trailers, dozers, graders, drills, scoops, shearers, man trains, and other mobile assets. By preventing problems before they start, mine operators can avoid more expensive equipment repairs.
From engine monitoring and vehicle location tracking to live video feeds of ore extraction, antennas support mining communications both aboveground and underground. Surface antennas are also used at fixed assets such as mine headquarters, processing plants, and large draglines that are built on-site, typically to remove overburden in strip mining operations. Sending signals over longer distances, such as from a remote headquarters to the entrance of a mine, can also pose challenges.
With long wall mining, the need to continuously reconfigure the mine means that communications networks must be ready to re-deploy. Machines with vehicle-mounted antennas aren’t the only moveable assets, however. Base stations, repeaters, and ceiling-mounted antennas are also re-located. “Shadow zones” don’t just pose risks to personnel either. They can prevent vehicles and machinery from sending and receiving messages via RFID or global positioning system (GPS) technology.
How Antennas Overcome Communications Challenges
The antennas that are used in mining operations must overcome obstructions and resist harsh environments. For optimal performance, systems engineers need to select products that can shape the radiation pattern to best fit the available space. For example, mining antennas that provide narrow beam-width coverage are a good choice for sending signals farther down tunnels. By contrast, mining antennas that are used with base stations typically feature broader radiation patterns.
Standard dipole antennas don’t receive reflected signals and may not be able to withstand dust, moisture, vibration, and impact. Multi-polarized antennas for mining applications send and receive signals in all polarizations, enabling reflected signals to become usable in non-line-of-sight (NLOS) situations. Importantly, these multi-polarized antennas are designed for rugged environments.
MP Antenna supplies multi-polarized mining network antennas with different radiation patterns in the vertical and horizontal planes.
- Directional antennas radiate in a single direction where typically higher gain is required.
- Omnidirectional antennas radiate radio wave power uniformly in all directions.
- Bidirectional antennas provide either front-and-rear or side-to-side coverage.
MP Antenna’s mining antennas support GPS, multiple feeds, various coax and connector types, and different mounting styles. Here at our facility in Elyria, Ohio, we design and manufacture mining antennas for sub 6 GHz applications such as UHF, VHF, wireless broadband systems, wireless mesh systems, and all 802.11 wireless systems. We also supply antennas that meet the UHF Gen2 standard for RFID, which typically operates between 900 and 915 MHz. Our antennas met MSHA standards within system designs, too.
In addition to radiation patterns, systems engineers that select antennas for mining communications need to consider the specific application environment. MP Antenna supplies products that are designed for underground, indoor, outdoor, and/or mobile uses. MP Antenna also offers custom solutions to meet specific demands of the mining industry, such as models that are designed to withstand high impact situations without compromising performance.