User's Manual

ASUS WLAN Adapter 33
Chapter 5
Chapter 5 - Glossary
Glossary
The 802.11b spectrum is plagued by saturation from wireless phones, microwave
ovens and other emerging wireless technologies, such as Bluetooth. In contrast,
802.11a spectrum is relatively free of interference.
The 802.11a standard gains some of its performance from the higher frequencies
at which it operates. The laws of information theory tie frequency, radiated power
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power and encoding scheme.
Compared with 802.11g:
802.11a is a standard for access points and radio NICs
that is ahead of 802.11g in the market by about six months. 802.11a operates in the
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you can have up to twelve access points set to different channels in the same
area without them interfering with each other. This makes access point channel
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LAN can deliver within a given area. In addition, RF interference is much less likely
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IEEE 802.11b (11Mbits/sec)
In 1997, the Institute of Electrical and Electronics Engineers (IEEE) adopted the
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standard includes provisions for three radio technologies: direct sequence spread
spectrum, frequency hopping spread spectrum, and infrared. Devices that comply
with the 802.11 standard operate at a data rate of either 1 or 2 Mbps.
In 1999, the IEEE created the 802.11b standard. 802.11b is essentially identical
to the 802.11 standard except 802.11b provides for data rates of up to 11 Mbps
for direct sequence spread spectrum devices. Under 802.11b, direct sequence
devices can operate at 11 Mbps, 5.5 Mbps, 2 Mbps, or 1 Mbps. This provides
interoperability with existing 802.11 direct sequence devices that operate only at 2
Mbps.
Direct sequence spread spectrum devices spread a radio signal over a range of
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into 14 overlapping operating Channels. Each Channel corresponds to a different
set of frequencies.
IEEE 802.11g
802.11g is a new extension to 802.11b (used in majority of wireless LANs today)
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OFDM (orthogonal frequency division multiplexing) technology. 802.11g allows
backward compatibility with 802.11b devices but only at 11 Mbps or lower,
depending on the range and presence of obstructions.
Infrastructure
A wireless network centered about an access point. In this environment, the access
point not only provides communication with the wired network but also mediates
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