BreadCrumb
®
ME3 User Guide
Rajant Corporation
Version: 1.02
03-100116-001
BreadCrumb channel configuration.
3.3 Physical Placement and other Considerations
Commonly occurring environmental factors have a significant impact on performance and behavior
of the BreadCrumb Wireless Network. LOS (Line of Sight) obstructions, distance, weather, and
device placement should all be considered when deploying a wireless network.
IEEE 802.11 wireless operation degrades gradually as distance increases between nodes or as
interference becomes prominent. This manifests as a data rate reduction between nodes.
The goal in planning and deploying a BreadCrumb Wireless Network is to maximize both coverage
and the data transfer rate between devices. These can be maximized by taking into consideration all
of the contributing factors described in this section.
3.3.1 Line-of-Sight
Unobstructed LOS (Line-of-Sight) is critical for optimal performance of the BCWN. Partial LOS
obstruction results in noticeable network performance degradation. Total LOS obstruction can result
in complete loss of network connectivity.
Elevating the device and external antenna will assist in providing better LOS. This can allow the
radio waves to propagate over some possible obstructions.
Unobstructed LOS is not necessary from every BreadCrumb device and wireless client to every
other BreadCrumb device and wireless client. However, each device must have unobstructed LOS
to the previous and subsequent device.
Client connectivity will degrade and drop if LOS to a BreadCrumb device can not be maintained.
3.3.2 Distance
Many factors determine acceptable distances between BreadCrumb devices when deploying a
BCWN:
•
If many devices are placed too closely together, it is possible that interference will degrade
the performance of the system.
•
Devices placed too far away or in RF “shadows” may experience total loss of connection.
•
RF transmit power and receive sensitivity are important in determining the distances over
which the device will be effective.
•
When placing a BreadCrumb device, check the connection status to the nearest available
device using either the BreadCrumb device’s status LED (described in section 1.3.5 Status
LED), or the BC|Commander management application. If the connection is poor or non-
existent, attempt to relocate the BreadCrumb device closer to another device until an
acceptable connection is obtained. If a poor connection or no connection is made at even
relatively close distances, you should refer to Chapter 5 Troubleshooting.
•
When the connection quality is found to be acceptable from BC|Commander, the distance of
the BreadCrumb device from the network can be increased until an optimal balance between
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