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The positioning of the antennas is crucial when AeroScout
®
tags are used for asset tracking and location
services. AeroScout
®
tags will not be read when there are antenna standing wave nulls. Antennas need
to be positioned to have best reception of tag messages.
For Antenna mounting options, see Antenna Mounting Options on page 27.
2.6 Determining Wi-Fi Distances between Wireless Network Switches
2.6.1 Line of Sight Distances
In line of sight, a WNS has a maximum wireless range of 300 metres (984 feet) using high gain directional
antennas. WNS units are generally installed with a 100 metre (328 feet) overlap of the radio field as shown
in
Figure 7: Wireless channel layout and distances . This ensures sufficient coverage between WNS units.
WNS units within range of each other must be configured with different Wi-Fi channels. By default every
fifth channel is used (channels 1, 6 and 11) to prevent signal overlap, minimising the possibility of
inter-modulation or interference.
Figure 7: Wireless channel layout and distances
2.6.2 Distances Around Curves
The wireless range of a WNS decreases when going around curves. In this case, WNS units need to be
installed closer together to provide sufficient coverage. Distances between WNS units will vary depending
on the drift and tightness of the curve. They are installed closer together on a tight curve.
Use the following steps to estimate the distance between WNS units:
1. Install one WNS unit at the beginning of the curve.
2. Install the second WNS unit between 20 metres (65 feet) to 40 metres (130 feet) from the end of the
curve.
3. Perform a RF signal strength test by walking from the first WNS to the second WNS.
4. If the strength test records levels of:
Wireless Network Switch User Manual 23 Revision A
Network System Design