Specifications

System Overview MP.11 5054-R/2454-R Installation and Management
Changing Basic Configuration Information
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893. Once fully operational on a frequency, the BSU actively monitors the occupied frequency for radar interference.
If radar interference is detected, the BSU blacklists the channel, logs a message and rescans to find a new frequency
free of radar interference.
Radar detection is performed only by the BSU and not by the SU. When an SU is set to a country in which DFS is
used, it scans all available channels upon startup looking for a BSU that best matches its connection criteria (such as
Base Station System Name, Network Name, and Shared Secret). The SU connects to the BSU automatically on
whatever frequency the BSU has selected. Because of this procedure, it is best to set up the BSU and have it fully
operational before installing the SU, although this is not required. If a BSU rescans because of radar interference, the
SU loses its wireless link. The SU waits 30 seconds (when the Mobility feature is enabled, the SU starts scanning for
a BSU instantly rather than waiting 30 seconds); if it finds that it could not receive the BSU in this amount of time, it
rescans the available frequencies for an active BSU.
2. Guarantee the efficient use of available frequencies by all devices in a certain area. To meet this requirement, the
BSU scans each available frequency upon startup and selects a frequency based upon the least amount of noise and
interference detected. This lets multiple devices operate in the same area with limited interference. This procedure is
done only at startup; if another non-radar device comes up on the same frequency, the BSU does not detect this or
rescan because of it. It is expected that other devices using these frequencies also are in compliance with country
regulations, so this should not happen.
Transmit Power Control
Transmit Power Control is a manual configuration selection to reduce the unit’s output power. The maximum output
power level for the operating frequency can be found in the event log of the unit’s embedded software.
By default, the unit lets you transmit at the maximum output power that the radio can sustain for data rate and frequency
selected. However, with Transmit Power Control (TPC), you can adjust the output power of the unit to a lower level in
order to reduce interference to neighboring devices or to use a higher gain antenna without violating the maximum
radiated output power allowed for your country. Also, most countries in the ETSI regulatory domain require the transmit
power to be set to a 6 dB lower value than the maximum allowed EIRP when link quality permits, as part of the DFS
requirements.
You can see your unit’s current output power for the selected frequency in the event log. The event log shows the
selected power for all data rates, so you must look up the relevant data rate to determine the actual power level.
NOTE: This feature only lets you decrease your output power; you cannot increase your output power beyond the
maximum the radio allows for your frequency and data rate.
See System Status to configure Country. See Configure the Wireless Interface to configure Transmit Power Control.