Published on November 26th, 2018 | by Yangkai Sun0
WIFI MESH: WHAT IS IT, WHY USE IT?
In the mining industry, where short periods of operational downtime can cause millions of dollars in lost opportunity, operations must be empowered to continuously monitor, manage and control their fleet of high-value mining equipment, vehicles and personnel – wherever these assets may travel across large areas of rugged mining terrain. A WiFi mesh network could be an ideal communications infrastructure to meet the requirements of these critical applications.
What is it?
Wireless mesh network (WMN) is a mesh network created through the interconnection of wireless access points which are installed in fixed locations or on mobile vehicles. Each network user (AP) is also a provider, forwarding data to the next node. The networking infrastructure is decentralised and simplified because each node need only transmit as far as the next node.
Depending on the use case, this may allow the network to span large distances, provide high data rates, and maintain connections over rough terrain. Mesh networks are also reliable, as each node may form connections to several other nodes. If one node drops out of the network, due to hardware failure or any other reason, the network nodes reorganise their link paths to find an efficient way for traffic to traverse the network.
Why use it?
Some of the benefits associated with a WiFi mesh network include:
- Instant, automatic formation of wireless networks;
- Self-forming, self-healing, and self-balancing. Mesh networks are inherently more robust than traditional wireless networks. Automatic configuration and routing enable networks to be self-forming and self-healing. The network continues to function with one or more node failures as long as a path can be found between the nodes; and
- Lower infrastructure and operational costs. Most mesh networks require less backhaul than a traditional wireless network which can greatly reduce deployment and operating expenses.
Reasons why WiFi mesh can be a resilient option for connectivity
Sharing the communication infrastructure with operations functions, maintenance and other support systems such as environmental monitoring and safety systems means the investment on the wireless infrastructure can be fully realised over several different services.
Choosing a wireless mesh network means that although many mining systems are sharing the infrastructure, a single point of failure will not affect normal operations. The mesh networks allow for redundancy with overlapped coverage (with dynamic channel assignment enabled), adaptive mesh communications and multiple access points to cabled services in case of primary link failure. Utilising these features, networks can be planned to survive equipment outages with minimal impact on mining support systems.
The following case study outlines a scenario where Titan ICT was engaged to deliver a wireless network solution to support various mining operation applications in the pit area.
The client is operating an open pit coal mine in central Queensland, which has deep and narrow pits that are highly terrain limited in terms of radio coverage. An in-pit wireless network is required to provide sufficient network coverage and capacity for the fleet management system, fuel management system and remote telemetry systems installed on site. This network is required to cover the mining lease area and provide robust and reliable service for up to 15 years (on a 5-year refresh basis). The network needs to be capable of adapting to the ever-changing profile of the mining area, through simple cost-effective changes and modifications to maintain network service and performance.
Some of the challenges that presented during the systems integration project included:
- Reliable network operation 24/7 in a dusty, hot environment (to +40°C).
- Flexibility to easily relocate network nodes around active excavation site and seamlessly scale the network as additional nodes and coverage area is required.
- Capacity to support multiple IP applications concurrently including fleet management, fuel polling system, tire pressure and temperature monitoring system, video cameras, lightning alert system, surface mine telematics, and mobile client Wi-Fi access.
- Centralised network visibility, management, and troubleshooting.
- Cost effective to deploy and operate.
After evaluating several wireless solutions, a WiFi mesh network was selected. It was the best solution that met all the requirements which included reliable high capacity communications with the ability to operate in the extreme heat and dust of the mining area.
Field proven, high capacity, WiFi mesh networks have demonstrated the capability to provide high reliability in environments of extreme temperatures.
Mobile Access Points on trailers are easily relocated and automatically associate with the network as they are moved to different locations around the mine. While WiFi access points provide a smaller coverage area than LTE or WiMax base stations, the infrastructure required to support them is less costly.
In summary, where mine radio coverage is very terrain limited, WiFi mesh can provide a robust wireless solution with a lower overall cost compared to an LTE or WiMax network.