Overview of IEEE 802.11 Wireless Lan Technology
by Allan Ampoloquio
Wireless LAN (WLAN) is a wireless broadband technology that utilizes radio
frequency (RF) to transmit and receive data through the air, minimizing the need
for wired networks.
There are two competing RF technologies in the use of Wireless LAN, the IEEE
802.11 standard and proprietary technologies. Both fall under wireless broadband
technology. Broadband means the ability to transmit high-speed voice, data and
video traffic using a wide range of frequencies on a single wireless medium or device.
This page aims to give you an overview about Wireless Broadband -IEEE 802.11
standard commonly called Wireless LAN. 802.11 is a standard agreed by the IEEE
(Institute of Electrical and Electronics Engineers, Inc.) the world's leading
professional association for the advancement of technology. 802.11 is the
standard adopted by IEEE to define an over the air interface between a wireless
client and base station or between two wireless clients.
The 802.11 standard has evolved over the years and became one of the most successfully
deployed technologies. The standard now covers 802.11b, 802.11a and 802.11g systems.
Radio Frequency (RF) is the medium use by wireless networks in the transmission
of information over the air. RF works by converting electrical current into
radio waves and transmit those waves over the air using a defined frequency of
the radio spectrum. An example, the AM and FM radios two most commonly known
uses of the RF spectrum.
The Federal Communications Commission (FCC) is the one administering the use of
radio spectrum between the frequencies of 9 Kilohertz (KHz) and 300 gigahertz
(GHz). 802.11 WLAN systems operate in the radio spectrum available to the public,
also known as the unlicensed frequency band. These radio spectrum bands are
unlicensed, free for use by anyone provided FCC regulations are complied with.
The FCC as a regulatory governs the maximum transmit power of wireless radios as
well as, type of encoding and frequency modulations to be used. In 802.11
operations, it is provided for by the FCC that non-licensed radios (such as
802.11) must accept interference from licensed electronic systems. FCC considers
licensed device as the primary equipment.
802.11 Wireless LAN Standard Operating Frequencies: The 802.11 standard are
assigned frequencies 2.4 GHz (2.4-2.4835 GHz) on ISM Band and 5 GHz (5.15-5.25
GHz, G.25-5.35 GHz, 5.725-5.825 GHz) of the U-NII band. 802.11b and 802.11g
operates on 2.4 GHz while 802.11a is operating on the 5 GHz band.
802.11 assigned frequency range has different characteristics. Lower Frequencies
(2.4 GHz ) exhibit better range but with limited bandwidth and lower data rates.
Higher Frequencies (5 GHz) have less range but higher data rates but is prone to
blocking by solid objects.