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CN1100 Access Point - Installation Guide - G7601 - 3.8
On initialization, the CN1100:
Applies random backoff (in 10s of seconds)
Scans the preferred and enabled channels
Applies the table rules (interference, loading, and beacon SINR)
Selects the best channel
Begins operating
The CN1100 uses the described rules table to select a channel based on the following input:
Scanning logs the SINR and loading of an xMax signal on each preferred channel.
Scanning logs the relative noise floor of each preferred channel.
A decision engine chooses the best channel to use based upon the conditions of that channel.
The channel with the lowest xMax SINR and noise floor, but still below a maximum allowable
threshold as set in the internal table, is claimed and used.
If no channels with xMax signals below the maximum threshold are found, no channel is
claimed and this condition is reported to xMonitor/SNMP.
An CN1100 in the “no channel available” condition waits a specified time and then begins
channel scanning for an available channel.
From time to time, the CN1100 scans for a better channel. A better channel is defined the same way
the channels were graded in the initial scan. However, just because there is a better channel from the
CN1100 receiver perspective, this is not necessarily a mandate to change channels.
The CN1100 makes a periodic scan on a timed interval or when the channel reaches a determined
error or noise threshold. This threshold or timing is set so that channel is unusable or idle. Mobile
devices use their preferred channel list to hand off to another CN1100, if available. In this case, the
bridge devices, xMods and xVMs, scan until they reacquire a CN1100.
In order for SON to work, as well as handoff or DSA, the xMod/xVM must always scan in the
background to build a preferred channel list. This list includes all available channels, as these devices
are mobile and may move into locations that have different channel sets or different excluded
channels.
