The IEEE (Institute of Electrical and Electronics Engineers) is
an international communications standards body responsible for:
802.11 (WiFi), 802.15 (Bluetooth, Wireless USB), 802.16 (WiMAX),
802.3 (Ethernet). Equipment manufacturers of these technologies
must conform to the IEEE specifications to ensure compatibility.
The current 802.11 (WiFi) standard was ratified by IEEE in 1999,
which included 802.11a for the 5 Ghz band offering data rates of
up to 54 Mbps using OFDM modulation (PSK/QAM), and 802.11b for
the 2.4 Ghz band offering data rates of up to 11 Mbps using DSSS
modulation (CCK).
In 2003 the 802.11g standard was ratified, which allowed 54 Mbps
data rates in the 2.4 Ghz spectrum by using OFDM modulation, and
also incorporating an automatic fallback to the 802.11b
standard.
Later equipment
manufacturers introduced proprietary (and non-compatible)
versions of 802.11g offering data rates of up to 108 Mbps by
using MIMO (Multiple-In, Multiple-Out) to transmit on 2
non-overlapping channels at the same time.
All IEEE standards are available on-line and free to download:
