IEEE 802.11a-1999
Generation | IEEE standard |
Adopted | Maximum link rate (Mbit/s) |
Radio frequency (GHz) |
---|---|---|---|---|
Wi-Fi 8 | 802.11bn | 2028[1] | 100,000[2] | 2.4, 5, 6, 7, 42.5, 71[3] |
Wi-Fi 7
|
802.11be | 2024 | 1376–46,120 | 2.4, 5, 6[4] |
Wi-Fi 6E
|
802.11ax
|
2020 | 574–9608[5] | 6[a] |
Wi-Fi 6 | 2019 | 2.4, 5 | ||
Wi-Fi 5
|
802.11ac | 2014 | 433–6933 | 5[b] |
Wi-Fi 4
|
802.11n | 2008 | 72–600 | 2.4, 5 |
(Wi-Fi 3)* | 802.11g | 2003 | 6–54 | 2.4 |
(Wi-Fi 2)* | 802.11a | 1999 | 5 | |
(Wi-Fi 1)* | 802.11b | 1999 | 1–11 | 2.4 |
(Wi-Fi 0)* | 802.11 | 1997 | 1–2 | 2.4 |
*Wi‑Fi 0, 1, 2, and 3 are named by retroactive inference. They do not exist in the official nomenclature.[6][7][8] |
IEEE 802.11a-1999 or 802.11a was an amendment to the IEEE 802.11 wireless local network specifications that defined requirements for an orthogonal frequency-division multiplexing (OFDM) communication system. It was originally designed to support wireless communication in the unlicensed national information infrastructure (U-NII) bands (in the 5–6 GHz frequency range) as regulated in the United States by the Code of Federal Regulations, Title 47, Section 15.407.
Originally described as clause 17 of the 1999 specification, it is now defined in clause 18 of the 2012 specification and provides protocols that allow transmission and reception of data at rates of 1.5 to 54 Mbit/s. It has seen widespread worldwide implementation, particularly within the corporate workspace. While the original amendment is no longer valid, the term "802.11a" is still used by wireless access point (cards and routers) manufacturers to describe interoperability of their systems at 5.8 GHz, 54 Mbit/s (54 x 106 bits per second).
Description
IEEE802.11a is the first wireless standard to employ packet based OFDM, based on a proposal from Richard van Nee
Using the 5 GHz band gives 802.11a a significant advantage, since the 2.4 GHz band is heavily used to the point of being crowded. Degradation caused by such conflicts can cause frequent dropped connections and degradation of service. However, this high
Regulatory issues
Different countries have different regulatory support, although a 2003 World Radiotelecommunications Conference improved worldwide standards coordination. 802.11a was quickly approved by regulations in the
Timing and compatibility of products
802.11a products started shipping late, lagging 802.11b products due to 5 GHz components being more difficult to manufacture. First generation product performance was poor and plagued with problems. When second generation products started shipping, 802.11a was not widely adopted in the consumer space primarily because the less-expensive 802.11b was already widely adopted. However, 802.11a later saw significant penetration into enterprise network environments, despite the initial cost disadvantages, particularly for businesses which required increased capacity and reliability over 802.11b/g-only networks.
With the arrival of less expensive early 802.11g products on the market, which were backwards-compatible with 802.11b, the bandwidth advantage of the 5 GHz 802.11a was eliminated. Manufacturers of 802.11a equipment responded to the lack of market success by significantly improving the implementations (current-generation 802.11a technology has range characteristics nearly identical to those of 802.11b), and by making technology that can use more than one band a standard.
Dual-band, or dual-mode Access Points and Network Interface Cards (NICs) that can automatically handle a and b/g, are now common in all the markets, and very close in price to b/g- only devices.
Technical description
Of the 52 OFDM subcarriers, 48 are for data and 4 are
RATE bits | Modulation type |
Coding rate |
Data rate ( Mbit/s)[c]
|
---|---|---|---|
1101 | BPSK |
1/2 | 6 |
1111 | BPSK |
3/4 | 9 |
0101 | QPSK |
1/2 | 12 |
0111 | QPSK |
3/4 | 18 |
1001 | 16- QAM |
1/2 | 24 |
1011 | 16- QAM |
3/4 | 36 |
0001 | 64- QAM |
2/3 | 48 |
0011 | 64- QAM |
3/4 | 54 |
- ^ Wi-Fi 6E is the industry name that identifies Wi-Fi devices that operate in 6 GHz. Wi-Fi 6E offers the features and capabilities of Wi-Fi 6 extended into the 6 GHz band.
- ^ 802.11ac only specifies operation in the 5 GHz band. Operation in the 2.4 GHz band is specified by 802.11n.
- ^ The data rate is for 20 MHz channel spacing.
Comparison
Frequency range, or type |
PHY | Protocol | Release date [11] |
Frequency | Bandwidth | Stream data rate [12] |
Allowable MIMO streams |
Modulation | Approximate range | |||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Indoor | Outdoor | |||||||||||
(GHz) | (MHz) | (Mbit/s) | ||||||||||
1–7 GHz | DSSS[13], |
802.11-1997 | June 1997 | 2.4 | 22 | 1, 2 | — | DSSS, |
20 m (66 ft) | 100 m (330 ft) | ||
HR/DSSS [13] | 802.11b | September 1999 | 2.4 | 22 | 1, 2, 5.5, 11 | — | CCK, DSSS | 35 m (115 ft) | 140 m (460 ft) | |||
OFDM | 802.11a | September 1999 | 5 | 5, 10, 20 | 6, 9, 12, 18, 24, 36, 48, 54 (for 20 MHz bandwidth, divide by 2 and 4 for 10 and 5 MHz) |
— | OFDM | 35 m (115 ft) | 120 m (390 ft) | |||
802.11j | November 2004 | 4.9, 5.0 [B][14] |
? | ? | ||||||||
802.11y | November 2008 | 3.7 [C] | ? | 5,000 m (16,000 ft)[C] | ||||||||
802.11p | July 2010 | 5.9 | 200 m | 1,000 m (3,300 ft)[15] | ||||||||
802.11bd | December 2022 | 5.9, 60 | 500 m | 1,000 m (3,300 ft) | ||||||||
ERP-OFDM[16] | 802.11g | June 2003 | 2.4 | 38 m (125 ft) | 140 m (460 ft) | |||||||
HT-OFDM [17] | 802.11n (Wi-Fi 4) |
October 2009 | 2.4, 5 | 20 | Up to 288.8[D] | 4 | QAM )
|
70 m (230 ft) | 250 m (820 ft)[18] | |||
40 | Up to 600[D] | |||||||||||
VHT-OFDM [17] | 802.11ac (Wi-Fi 5) |
December 2013 | 5 | 20 | Up to 693[D] | 8 | DL QAM )
|
35 m (115 ft)[19] | ? | |||
40 | Up to 1600[D] | |||||||||||
80 | Up to 3467[D] | |||||||||||
160 | Up to 6933[D] | |||||||||||
HE-OFDMA | ) | May 2021 | 2.4, 5, 6 | 20 | Up to 1147[E] | 8 | UL/DL QAM )
|
30 m (98 ft) | 120 m (390 ft) [F] | |||
40 | Up to 2294[E] | |||||||||||
80 | Up to 5.5 Gbit/s[E] | |||||||||||
80+80 | Up to 11.0 Gbit/s[E] | |||||||||||
EHT-OFDMA | Wi-Fi 7 )
|
Dec 2024 (est.) |
2.4, 5, 6 | 80 | Up to 11.5 Gbit/s[E] | 16 | UL/DL QAM )
|
30 m (98 ft) | 120 m (390 ft) [F] | |||
160 (80+80) |
Up to 23 Gbit/s[E] | |||||||||||
240 (160+80) |
Up to 35 Gbit/s[E] | |||||||||||
320 (160+160) |
Up to 46.1 Gbit/s[E] | |||||||||||
UHR | 802.11bn (Wi-Fi 8) |
May 2028 (est.) |
2.4, 5, 6, 42, 60, 71 |
320 | Up to 100000 (100 Gbit/s) |
16 | Multi-link QAM )
|
? | ? | |||
WUR [G] | 802.11ba | October 2021 | 2.4, 5 | 4, 20 | 0.0625, 0.25 (62.5 kbit/s, 250 kbit/s) |
— | OOK (multi-carrier OOK)
|
? | ? | |||
mmWave (WiGig) |
DMG [20] | 802.11ad | December 2012 | 60 | 2160 (2.16 GHz) |
Up to 8085[21] (8 Gbit/s) |
— | 3.3 m (11 ft)[22] | ? | |||
802.11aj
|
April 2018 | 60 [H] | 1080[23] | Up to 3754 (3.75 Gbit/s) |
— | single carrier, low-power single carrier[A] | ? | ? | ||||
CMMG | 802.11aj
|
April 2018 | 45 [H] | 540, 1080 |
Up to 15015[24] (15 Gbit/s) |
4 [25] | OFDM, single carrier | ? | ? | |||
EDMG [26] | 802.11ay | July 2021 | 60 | Up to 8640 (8.64 GHz) |
Up to 303336[27] (303 Gbit/s) |
8 | OFDM, single carrier | 10 m (33 ft) | 100 m (328 ft) | |||
Sub 1 GHz ( IoT )
|
TVHT [28] | 802.11af | February 2014 | 0.054– 0.79 |
6, 7, 8 | Up to 568.9[29] | 4 | MIMO-OFDM | ? | ? | ||
S1G [28] | 802.11ah | May 2017 | 0.7, 0.8, 0.9 |
1–16 | Up to 8.67[30] (@2 MHz) |
4 | ? | ? | ||||
Light (Li-Fi) |
LC ( VLC/OWC )
|
802.11bb | December 2023 (est.) |
800–1000 nm | 20 | Up to 9.6 Gbit/s | — | O- OFDM
|
? | ? | ||
IrDA )
|
802.11-1997 | June 1997 | 850–900 nm | ? | 1, 2 | — | ? | ? | ||||
802.11 Standard rollups | ||||||||||||
802.11-2007 (802.11ma) | March 2007 | 2.4, 5 | Up to 54 | DSSS, OFDM | ||||||||
802.11-2012 (802.11mb) | March 2012 | 2.4, 5 | Up to 150[D] | DSSS, OFDM | ||||||||
802.11-2016 (802.11mc) | December 2016 | 2.4, 5, 60 | Up to 866.7 or 6757[D] | DSSS, OFDM | ||||||||
802.11-2020 (802.11md) | December 2020 | 2.4, 5, 60 | Up to 866.7 or 6757[D] | DSSS, OFDM | ||||||||
802.11me | September 2024 (est.) |
2.4, 5, 6, 60 | Up to 9608 or 303336 | DSSS, OFDM | ||||||||
|
See also
- Clear channel assessment attack
- List of WLAN channels
- OFDM system comparison table
- Spectral efficiency comparison table
References
- . Retrieved 2024-05-21.
- ^ "What is Wi-Fi 8?". everythingrf.com. March 25, 2023. Retrieved January 21, 2024.
- arXiv:2303.10442.
- ^ "Understanding Wi-Fi 4/5/6/6E/7". wiisfi.com.
- ^ "MCS table (updated with 80211ax data rates)". semfionetworks.com.
- ^ Kastrenakes, Jacob (2018-10-03). "Wi-Fi Now Has Version Numbers, and Wi-Fi 6 Comes Out Next Year". The Verge. Retrieved 2019-05-02.
- ^ Phillips, Gavin (18 January 2021). "The Most Common Wi-Fi Standards and Types, Explained". MUO - Make Use Of. Archived from the original on 11 November 2021. Retrieved 9 November 2021.
- ^ "Wi-Fi Generation Numbering". ElectronicsNotes. Archived from the original on 11 November 2021. Retrieved 10 November 2021.
- ^ Van Nee, Richard (January 1998). "OFDM physical layer specification for the 5 GHz band". IEEE P802.11-98/12.
- ^ Van Nee, Richard; Prasad, Ramjee (December 1999). "OFDM for Mobile Multimedia Communications". Boston: Artech House.
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: Cite magazine requires|magazine=
(help) - ^ "Official IEEE 802.11 working group project timelines". January 26, 2017. Retrieved 2017-02-12.
- ^ "Wi-Fi CERTIFIED n: Longer-Range, Faster-Throughput, Multimedia-Grade Wi-Fi Networks" (PDF). Wi-Fi Alliance. September 2009.
- ^ arXiv:1307.2661.
- ^ "The complete family of wireless LAN standards: 802.11 a, b, g, j, n" (PDF).
- ^ The Physical Layer of the IEEE 802.11p WAVE Communication Standard: The Specifications and Challenges (PDF). World Congress on Engineering and Computer Science. 2014.
- ^ IEEE Standard for Information Technology- Telecommunications and Information Exchange Between Systems- Local and Metropolitan Area Networks- Specific Requirements Part Ii: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications. (n.d.). doi:10.1109/ieeestd.2003.94282
- ^ a b "Wi-Fi Capacity Analysis for 802.11ac and 802.11n: Theory & Practice" (PDF).
- ^ Belanger, Phil; Biba, Ken (2007-05-31). "802.11n Delivers Better Range". Wi-Fi Planet. Archived from the original on 2008-11-24.
- ^ "IEEE 802.11ac: What Does it Mean for Test?" (PDF). LitePoint. October 2013. Archived from the original (PDF) on 2014-08-16.
- .
- ^ "802.11ad - WLAN at 60 GHz: A Technology Introduction" (PDF). Rohde & Schwarz GmbH. November 21, 2013. p. 14.
- ^ "Connect802 - 802.11ac Discussion". www.connect802.com.
- ^ "Understanding IEEE 802.11ad Physical Layer and Measurement Challenges" (PDF).
- ^ "802.11aj Press Release".
- .
- ^ "IEEE 802.11ay: 1st real standard for Broadband Wireless Access (BWA) via mmWave – Technology Blog". techblog.comsoc.org.
- ^ "P802.11 Wireless LANs". IEEE. pp. 2, 3. Archived from the original on 2017-12-06. Retrieved Dec 6, 2017.
- ^ a b "802.11 Alternate PHYs A whitepaper by Ayman Mukaddam" (PDF).
- ^ "TGaf PHY proposal". IEEE P802.11. 2012-07-10. Retrieved 2013-12-29.
- .
- General
- "802.11a-1999 High-speed Physical Layer in the 5 GHz band" (PDF). 1999-02-11. Retrieved 2007-09-24.