User's Manual

Rajant Corporation BreadCrumb® ME4 v11 User Guide
03-100126-011 Version 11.0.0
Table 3: Default Channel Assignments
Radio Card Frequency Default Channel
900 MHz 5
2.4 GHz 11
4.9 GHz 20
5 GHz 153
In some cases, it may be necessary to manually set the radios to specific channels to provide critical
links within a mesh. This can be especially important when using single-radio BreadCrumb devices.
Refer to the BC|Commander v11 User Guide for the details of BreadCrumb channel configuration.
4.3 Physical Placement and other Considerations
Commonly occurring environmental factors have a significant impact on performance and behavior of
the BreadCrumb Wireless Network. Line-of-sight (LOS) 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 mesh 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.
4.3.1 Line-of-Sight
Unobstructed line-of-sight (LOS) is critical for optimal performance of the mesh. 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.
4.3.2 Distance
Many factors determine acceptable distances between BreadCrumb devices when deploying a mesh:
● If many devices are placed too closely together, it is possible that interference will degrade the
performance of the system.
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