Alvarion BreezeACCESS EZ AU-EZ, Системное руководство

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Chapter 4 - Operation and Administration Menus and Parameters
BreezeACCESS EZ AU-EZ 72 System Manual
and 5810 MHz should not be used as well. These frequencies are marked in the
database as Adjacent to Radar, and will be treated the same as Radar Detected
frequencies.
4.2.6.2.2.2.2 DFS implementation on the SU
When DFS is enabled on the SU, the unit uses a channel availability check
mechanism that is similar to the AU’s. Before associating to the AU, the SU picks
a Radar Free frequency and:

If the frequency was previously scanned and tagged as available, it
immediately associates to the AU.

If the frequency is currently tagged as Radar Free as a result of a Radar
Detected status that expired, or in some cases if the Radar Free validation has
expired (see the note above), the SU will initiate its own channel availability
check. As a result:
»
If no radar signal is detected, the SU associates to the AU
»
If the SU detects a radar, it will tag the frequency in its own database as
Radar Detected, notify the AU and attempt to connect on another channel
While associated, the SU also performs In-Service Monitoring, meaning that it
periodically scans the operating channel for radar signals. If radar is detected, it
will notify the AU and stop transmitting on the respective frequency.
ETSI requirements enforce particular implementations for the DFS functionality
on CPEs. Implementations of DFS on the SU for ETSI 5.8 and ETSI 5.4 based
country codes are compared in
Table 4-5 .
NOTE
Some country codes require a periodical revalidation of the Radar Free frequencies. So additionally,
it might be required for the channel validation period not to have expired as well.
Table 4-5: DFS behavior on SUs using ETSI based country codes
Feature ETSI 5.8 based country codes ETSI 5.4 based country codes
Applicable country
codes
 ETSI 5.8
 Other country codes based on ETSI 5.8
(UK 5.8, Germany 5.8 and Universal
5.8 with Detection Algorithm set to
ETSI)
 ETSI 5.4
 Other country codes based on ETSI 5.4
(ETSI F 5.4 and Universal 5.4 with
Detection Algorithm set to ETSI)