Protocol Date Frequency
(GHz)
802.11-1997 Jun-97 2.4 22 1, 2 N/A DSSS, FHSS
802.11ad Dec-12 60 2,160 Up to 6, 7 Gb/s N/A
Table does not include all standards released in this period or those in progress due to be released later. The releases
prior to 802.11n are provided to show the history of the 802.11 working group.
10 I ICT TODAY
OFDM,
single carrier,
low-power
single carrier
802.11a Sep-99
5
20 Up to 54 N/A OFDM
802.11b Sep-99 2.4 22 Up to 11 N/A DSSS
802.11g Jun-03 2.4 20 Up to 54 N/A OFDM
802.11n
20 Up to 288.8
(Wi-Fi 4) Oct-09 2.4/5
Up to 600
4 MIMO-OFDM
802.11ac
(Wi-Fi 5) Dec-13 5
20 Up to 346.8
40 Up to 800
80 Up to 1733.2
160 Up to 3466.8
8 MIMO-OFDM
802.11ax
(Wi-Fi 6) End of 2019? 2.4/5 Up to 10,530
(10.53 Gb/s) MIMO-OFDM
Release
Bandwidth
(MHz)
Stream
Data Rate
(Mbit/s)
Allowable
MIMO
Streams
Modulation
TABLE 1: IEEE 802.11 network physical layer (PHY) standards.
Based on multiple-input-multiple-output (MIMO)
antennas, 802.11n operates on 20 and 40 megahertz
(MHz) wide channels in both the 2.4 and 5 gigahertz
(GHz) bands with a potential data rate of 54 to 600
megabits per second (Mb/s). 802.11n uses a modulation
technique called 64 quadrature amplitude modulation,
commonly referred to as 64 QAM.
OTHER IMPORTANT STANDARDS INCLUDE:
802.11ac: This is the current Wi-Fi standard, built on
the same technology of 802.11n using MIMO antennas,
but it adds multi-user capability (MU-MIMO) and a
higher-order modulation form called 256 QAM. The
standard, published in 2013, now uses only the 5 GHz
UNII and ISM bands with higher bandwidth channels,
80 MHz and 160 MHz, with a maximum of eight
spatial streams. The theoretical maximum data rate is
nearly 7 gigabits per second (Gb/s), but manufacturers
have developed 802.11ac in two waves. Wave 1 devices
were the first to hit the market and are limited to 80
MHz channels and a theoretical high-end throughput
of 1.3 Gb/s. Wave 2 devices are fully utilizing the
specifications to achieve up to 6.67 Gb/s throughputs.
Most manufacturers have used the 802.11ac standards to
develop their products and are Wi-Fi certified. This is the
most common technology in new Wi-Fi installations.
802.11ad/WiGig: The term “millimeter wave” applies
to all frequencies between 30 GHz with a wavelength of
10 millimeters (mm), and 300 GHz with a wavelength of
3.7
40