Access Point High-Speed WAN Interface Cards
Access Point High-Speed WAN Interface Cards
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OL-12854-01
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The density of the materials used in a building's construction determines the number of walls the
signal must pass through and still maintain adequate coverage. Consider the following before
choosing the location to install your antenna:
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Paper and vinyl walls have very little effect on signal penetration.
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Solid and precast concrete walls limit signal penetration to one or two walls without degrading
coverage.
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Concrete and wood block walls limit signal penetration to three or four walls.
–
A signal can penetrate five or six walls constructed of drywall or wood.
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A thick metal wall or wire-mesh stucco walls causes signals to reflect back and cause poor
penetration.
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Avoid mounting the antenna next to a column or vertical support that could create a shadow zone
and reduce the coverage area.
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Keep the antenna away from reflective metal objects such as heating and air-conditioning ducts,
large ceiling trusses, building superstructures, and major power cabling runs. If necessary, use an
extension cable to relocate the antenna away from these obstructions.
Caution
Install the access point HWIC and any antennas away from appliances that share the same frequency
bands. Microwave ovens, cordless telephones, and security monitors can temporarily interfere with
wireless performance.
Caution
We recommend you avoid installing wireless antennas in or near rack-mounted installations that include
networking equipment and computer servers whose radiated noise emissions can severely degrade radio
performance.
Note
If the desired installation site has a marginally acceptable level of radiated noise emissions, consider
using a remote-mounted antenna, such as a wall-mount or ceiling-mount antenna, for better radio
performance and coverage.
Swivel-Mount Dipole Antennas
If you are using Cisco swivel-mount dipole antennas, follow these steps:
Step 1
Attach an antenna to each of the RP-TNC antenna connectors on the front of the access point HWIC and
tighten it hand-tight.
Step 2
Orient the antennas depending on how you intend to mount the router in which the access point HWIC
is installed.
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If the router is on a table or desk, orient the antennas to the left and right sides so that they are at a
90-degree angle to each other. (See
Figure 134
.)
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If the router is on a vertical surface, such as a wall, orient the antennas up and at a 90-degree angle
to each other.
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If the router is on a ceiling, orient the antennas down and at a 90-degree angle to each other.
