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2.1 Installation Types and Coverage
Wireless network coverage can be described as:
• Wi-Fi hotspot — Network coverage is provided in key areas, such as crib areas and refuge bays.
• Full coverage — Seamless wireless coverage by strategically placing WNS units so their radio fields
overlap.
A WNS can communicate at wireless distances of 150-300 meters, depending on the geometry and geology
of the mine.
2.2 Power Requirements
The power requirements for a network are unique to each site installation. Determining power requirements
can be complex and is dependent on various factors such as the number of WNS units, PoE devices,
branches in the network and composite cable lengths.
Note: A site inspection conducted by a MST System Engineer will help determine the power
requirements for your network.
The WNS is designed to operate at a wide voltage range, from a minimum of 10VDC up to 50VDC. Each
WNS in a network can internally step up the incoming voltage to 48VDC in order to supply power to
connected PoE devices. The WNS needs to receive a minimum input of 15VDC to power connected PoE
devices.
48VDC power supplies are used for large networks to maximise the distance between power supplies.
For smaller networks of 1-2 nodes, it is recommended that a lower voltage 24VDC power supply is used.
2.3 Choosing Antennas
Antennas are connected to each WNS to provide wireless network coverage. The type of wireless coverage,
surrounding geology, tunnel topology and stratum type are factors that will determine the choice of
antenna. A minimum of one antenna is required per WAC in a WNS.
Antennas consist of two directional patterns:
• Omnidirectional antennas — radiate equally in all directions for a short range, providing immediate
coverage in an open area.
• Directional antennas — radiate in a specific direction over a longer range. A higher gain antenna
will have a longer range and is more directional. It is important that directional antennas are aligned
properly between WNS units.
The antenna radiation pattern and polarisation need to be considered to provide suitable wireless coverage
in an area.
Antennas commonly used with the WNS are shown below.
Revision A 20 Wireless Network Switch User Manual
Network System Design