Intel 2200BG, Руководство пользователя

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a “typical” office building, where the walls may be simple drywall (which is almost
transparent to microwaves), or could be plaster with metal underneath. Most sites are
somewhere between these two extremes, and consist of a mixture of surfaces. You can’t
tell what is inside a wall by just looking at it, and we can’t tell you exactly what distance
you will achieve. Consider published range information to be typical, average, common
or usual. Do not expect it to be exact.
Signal strength drops when a cell phone is used in the area
Range also depends on the electronic environment. If other equipment that could cause
interference is nearby, the range of your transceiver could vary widely, and could change
suddenly when the other equipment activates. This is particularly true for 802.11b
installations, which share their frequencies with microwave ovens, cordless phones,
wireless hi-fi speakers, electronics toys and similar devices. Try to keep your system
away from other transmitters, and from other sources of electrical noise, such as large
motors, spot welders, and similar “electronically noisy” devices.
Range is shorter than it should be
Repeat some tests late in the evening, or on a weekend, when there may be less
interference. However, some users leave their networks turned all the time so this test is
not foolproof. By all means, try more than one channel. Your range problem may just be
a nearby user whose system uses your present test channel.
Interference from fluorescent lights
If you mount an access point close to fluorescent light fixtures, the lamp glow appears
constant, but inside the lamp tube, ionization appears and disappears 120 times a
second. This can modulate or “chop” an incoming signal and interfere with reception.
When too much range is undesirable
Too much range is not necessarily a good thing. At first it would appear that you would
want as much range as possible, but with the increase in range comes an increase in
interference potential, as your unit hears not only your other units but also manages to
hear the systems of other companies up and down the street. If you have a large
installation, you will also wind up with more than one access point using the same
channel. If a remote unit hears two or more access points, this will slow the network.