User guide

Canopy System User Guide Analyzing the RF Environment
pmp-0229 (Mar 2013)
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receives on that frequency for one minute without transmitting, as it monitors for a radar signature. Then
the slave proceeds as follows:
• If an SM detects no radar during this minute, it attempts to register in the AP. If it does detect
radar, it locks out that frequency for 30 minutes and continues scanning other frequencies in
its scan list.
• If a BHS detects no radar during this minute, it registers in the BHM. While registering and
ranging, it continues for another full minute to scan for radar. If it detects radar, it locks out
that frequency for 30 minutes and continues scanning other frequencies in its scan list.
The possibility exists for a slave to attempt to register in a different master at this point and to
even succeed. This would depend on both of the following conditions:
• matching color code values in the slave and master
• matching transmission frequency of the master to one that the slave is set in the scan list of
the slave.
The slave automatically inherits the DFS type of the master. This behavior ignores the value of the
Region Code parameter in the slave, even when the value is None. Nevertheless, since future
system software releases may read the value in order to configure some other region-sensitive
feature(s), the operator should always set the value that corresponds to the local region.
The Home => General Status web page in any module with DFS displays one of the following
status statements in its read-only field DFS field under Device Information:
• Normal Transmit
• Radar Detected Stop Transmitting for n minutes, where n counts down
from 30 to 1.
• Checking Channel Availability Remaining time n seconds, where n
counts down from 60 to 1.
• Idle, which indicates that the slave radio is scanning but has failed to detect a beacon from a
master radio. When it has detected a beacon, the slave initiates a channel availability check
(CAC) on that frequency.
RECOMMENDATION:
Where regulations require that radar sensing and radio shutdown is enabled, you
can most effectively share the spectrum with satellite services if you perform
spectrum analysis and select channels that are distributed evenly across the
frequency band range.
A connectorized 5.7-GHz module provides an Antenna Gain parameter. When you indicate the
gain of your antenna in this field, the algorithm calculates the appropriate sensitivity to radar
signals, and this reduces the occurrence of false positives (wherever the antenna gain is less than
the maximum).