Overview of IEEE 802.11 standard
ImasDé WLAN Product Family complies with IEEE 802.11
standard,
whose final revision was approved last June 1997. This standard defines
the operation and interoperability among wireless networks. The
IEEE
802.11 comittee has chosen the 2.4 GHz ISM band (Industrial, Scientific
and Medical) for a global WLAN standard definition, which is available
worldwide. The ISM bands are for unlicensed, being limited in transmit
power for local networks to 100 mW.
The IEEE 802.11 specification defines 2 Mbps as the maximum data
rate between wireless equipments, using Direct Sequence Spread Spectrum
(DSSS). This modulation technique is based on the substitution of each
data bit by an equivalent sequence of 11 bits, easily recognized by the
receiver, so even if some of the received signal spectrum has been affected
by interferences, the receiver will still be able of extract the data information
from it.
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