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RedMAX Administration and Maintenance Guide
Redline Communications Inc. Confidential and Proprietary
Unfortunately, no amount of planning can avoid interference caused by external sources,
or "rogue" sectors. If you suspect that you are experiencing problems due to external
interference, perform the spectrum sweep as outlined in Guide to Field Spectral Analysis.
If the spectrum tests shows any unknown source of interference in your bands, you need
to contact your local regulator, as the frequency spectrum used by the RedMAX system is
licensed.
Viewing Noise Level Measurements
RedMAX devices can report the background noise level as measured by the AN100U/UX
radio. This measurement is extremely useful when attempting to troubleshoot uplink
stability issues and CRC errors.
The reported value can be found in two locations:
•
At the beginning of the AN100U/UX's event log.
•
On the AN100U/UX's Web client Wireless Status page.
Each of the two values is measured slightly differently. In either case, the lower bound of
the value (interpreted as no detected background noise) is around -108.6dBm, depending
on the calibration of the individual radio.
If the noise level is greater than the lower bound, then it must be at least 30dBm less than
the sensitivity threshold of the current operating modulation/coding rate. If the noise level
is not 30dBm less than the sensitivity threshold, then it impacts signal quality (i.e. CINR).
Note
An elevated noise floor value is a strong indicator of interference in the uplink;
however, the absence of an elevated noise floor value does not necessarily indicate
the absence of interference. The noise floor value is one of many indicators that
must be considered. See “RF Interference” on page 5-29 for more details.
The noise floor value that is shown on the status page is an average value, that may not
reflect peak values. Please refer to “Noise Floor Calculation” on page B-20 for detailed
information on how this value is calculated.
AN100U/UX Event Log Value
The noise level reported in the AN100U/UX's event log on system boot-up is an
instantaneous value measured during the first 3 seconds after the AN100U/UX radio's
receive chain is powered up. This value is not updated or reported again.
See “Monitoring System Event Logs” on page 2-6, to view the sector controller event logs.
This value of this noise level measurement will result in one of 3 event log messages:
•
Average Noise Floor on the Uplink Channel = [dBm]
This message is part of normal system operation, and indicates that the radio was not
able to synchronize on any interfering signal.
•
WARNING: Uplink Channel Conflict with [sector controller MAC] (RSSI dBm)
