Cisco Cisco Aironet 1400 Wireless Bridge Guide De Montage
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Cisco Aironet 1400 Series Wireless Bridge Mounting Instructions
OL-7618-01
Stacking Bridges
Installing the Stacked Bridges
To install stacked bridges, refer to
as you follow these steps:
Step 1
Install the link 1 bridges (bridges A and C) normally, but leave room at each site to install the link 2
bridges (bridges B and C).
bridges (bridges B and C).
Step 2
Activate the link 1 bridges, align the antennas, and verify proper operation of the link.
Step 3
At each site location, choose a candidate location for the second bridge that is at least 8 feet away from
the first bridge. Separate the bridges as far as is practical from each other, keeping in mind that the
second antenna must have a clear path to the remote system.
the first bridge. Separate the bridges as far as is practical from each other, keeping in mind that the
second antenna must have a clear path to the remote system.
Step 4
At each site location, temporarily install the second link 2 bridge, positioning the antenna toward the
intended location of the corresponding link 2 remote antenna.
intended location of the corresponding link 2 remote antenna.
Note
You can improve system isolation by using different polarizations for the two local antennas. For
example, if the link 1 system has vertical polarization, assemble the link 2 system for horizontal
polarization.
example, if the link 1 system has vertical polarization, assemble the link 2 system for horizontal
polarization.
Verifying Isolation
Isolation measurements are valid only if the link 1 bridges are operating at maximum power. By default,
the bridge operates at maximum power.
the bridge operates at maximum power.
To verify signal isolation, refer to
as you follow these steps:
Step 1
Ensure that the link 1 bridges are operating at full power and bridge A is configured as the root bridge.
Step 2
At Site 1, measure the isolation between bridges A and B:
a.
Activate the link 2 bridge (bridge B) as a non-root bridge and let it associate to bridge A (the root
bridge).
bridge).
b.
Connect a voltmeter to the RSSI port of bridge B, and verify that the voltage is 1.95 volts (-40 dBm)
or less. If the voltage exceeds 1.95 volts, move the bridge farther away and repeat this procedure.
or less. If the voltage exceeds 1.95 volts, move the bridge farther away and repeat this procedure.
c.
Slowly rotate the bridge B antenna a few degrees to the left and to the right and verify that the RSSI
level does not rapidly spike above 1.95 volts. If the voltage peaks above 1.95 volts, move the bridge
farther away and repeat this step.
level does not rapidly spike above 1.95 volts. If the voltage peaks above 1.95 volts, move the bridge
farther away and repeat this step.
Step 3
Go to the remote Site 2 location to measure the isolation between bridges A and D:
a.
Activate the link 2 bridge (bridge D) as a non-root bridge and let bridge D associate to bridge A (the
root bridge).
root bridge).
b.
Connect a voltmeter to the RSSI port of bridge D and align the bridge D antenna with bridge A so that
the RSSI voltage is maximized.
the RSSI voltage is maximized.
c.
When the antennas are fully aligned, if the RSSI voltage level is greater than 1.95 volts, the bridge
sites are very close. Reduce the output power on all bridges at both sites (bridges A, B, C, and D) to
12 dBm.
sites are very close. Reduce the output power on all bridges at both sites (bridges A, B, C, and D) to
12 dBm.