IEEE 802.11ac
IEEE 802.11ac is a wireless networking standard in the 802.11 family (which is marketed under the brand name Wi-Fi), developed in the IEEE Standards Association process,[1] providing high-throughput wireless local area networks (WLANs) on the 5 GHz band.[1] The standard was developed from 2011 through 2013 and approved in January 2014.[1][2]
This specification has expected multi-station WLAN throughput of at least 1 gigabit per second and a single link throughput of at least 500 megabits per second (500 Mbit/s). This is accomplished by extending the air interface concepts embraced by 802.11n: wider RF bandwidth (up to 160 MHz), more MIMO spatial streams (up to eight), downlink multi-user MIMO (up to four clients), and high-density modulation (up to 256-QAM).[3][4]
New technologies
New technologies introduced with 802.11ac include the following:[4]
- Extended channel binding
- Mandatory 80 MHz channel bandwidth for stations (vs. 40 MHz maximum in 802.11n), 160 MHz available optionally
- More MIMO spatial streams
- Support for up to eight spatial streams (vs. four in 802.11n)
- Downlink Multi-user MIMO (MU-MIMO, allows up to four simultaneous downlink MU-MIMO clients)
- Multiple STAs, each with one or more antennas, transmit or receive independent data streams simultaneously
- “Space Division Multiple Access” (SDMA): streams not separated by frequency, but instead resolved spatially, analogous to 11n-style MIMO
- Downlink MU-MIMO (one transmitting device, multiple receiving devices) included as an optional mode
- Multiple STAs, each with one or more antennas, transmit or receive independent data streams simultaneously
- Modulation
- Other elements/features
- Beamforming with standardized sounding and feedback for compatibility between vendors (non-standard in 802.11n made it hard for beamforming to work effectively between different vendor products)
- MAC modifications (mostly to support above changes)
- Coexistence mechanisms for 20/40/80/160 MHz channels, 11ac and 11a/n devices
- Adds four new fields to the PPDU header identifying the frame as a Very High Throughput (VHT) frame as opposed to 802.11n's High Throughput (HT) or earlier. The first three fields in the header are readable by legacy devices to allow coexistence
Meru Networks has suggested that 802.11ac makes a wireless network employing the Single Channel Architecture substantially more effective.[5] Traditional 802.11 networks are deployed as a Multiple Channel Architecture
Mandatory and optional features
- Mandatory features (carried over from 802.11a/802.11g)
- 800 ns regular guard interval
- Binary convolutional coding (BCC)
- Single spatial stream
- New mandatory features (newly introduced in 802.11ac)
- 80 MHz channel bandwidths
- Optional features (carried over from 802.11n)
- two to four spatial streams
- Low-density parity-check code (LDPC)
- Space-Time Block Coding (STBC)
- Transmit Beamforming (TxBF)
- 400 ns short guard interval (SGI)
- Optional features (newly introduced in 802.11ac)
- five to eight spatial streams
- 160 MHz channel bandwidths (contiguous 80+80)
- 80+80 MHz channel bonding (discontiguous 80+80)
- MCS 8/9 (256-QAM)
New scenarios and configurations
The single-link and multi-station enhancements supported by 802.11ac enable several new WLAN usage scenarios, such as simultaneous streaming of HD video to multiple clients throughout the home, rapid synchronization and backup of large data files, wireless display, large campus/auditorium deployments, and manufacturing floor automation.[6]
With the inclusion of USB 3.0 interface, 802.11ac access points and routers can use locally attached storage to provide various services that fully utilize their WLAN capacities, such as video streaming, FTP servers, and personal cloud services.[7] With storage locally attached through USB 2.0, filling the bandwidth made available by 802.11ac was not easily accomplished.
Example configurations
All rates assume 256-QAM, rate 5/6:
Scenario | Typical client form factor | PHY link rate | Aggregate capacity (speed) |
---|---|---|---|
One-antenna AP, one-antenna STA, 80 MHz | Handheld | 433 Mbit/s | 433 Mbit/s |
Two-antenna AP, two-antenna STA, 80 MHz | Tablet, laptop | 867 Mbit/s | 867 Mbit/s |
One-antenna AP, one-antenna STA, 160 MHz | Handheld | 867 Mbit/s | 867 Mbit/s |
Three-antenna AP, three-antenna STA, 80 MHz | Laptop, PC | 1.27 Gbit/s | 1.27 Gbit/s |
Two-antenna AP, two-antenna STA, 160 MHz | Tablet, laptop | 1.69 Gbit/s | 1.69 Gbit/s |
Four-antenna AP, four one-antenna STAs, 160 MHz (MU-MIMO) | Handheld | 867 Mbit/s to each STA | 3.39 Gbit/s |
Eight-antenna AP, 160 MHz (MU-MIMO)
|
Digital TV, Set-top Box, Tablet, Laptop, PC, Handheld |
|
6.77 Gbit/s |
Eight-antenna AP, four 2-antenna STAs, 160 MHz (MU-MIMO) | Digital TV, tablet, laptop, PC | 1.69 Gbit/s to each STA | 6.77 Gbit/s |
Data rates and speed
Theoretical
Theoretical throughput for single spatial stream (in Mbit/s)[8][lower-alpha 1] | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
MCS index[lower-alpha 2] | Modulation type | Coding rate | 20 MHz channels | 40 MHz channels | 80 MHz channels | 160 MHz channels | ||||||
800 ns GI[lower-alpha 3] | 400 ns GI | 800 ns GI | 400 ns GI | 800 ns GI | 400 ns GI | 800 ns GI | 400 ns GI | |||||
0 | BPSK | 1/2 | 6.5 | 7.2 | 13.5 | 15 | 29.3 | 32.5 | 58.5 | 65 | ||
1 | QPSK | 1/2 | 13 | 14.4 | 27 | 30 | 58.5 | 65 | 117 | 130 | ||
2 | QPSK | 3/4 | 19.5 | 21.7 | 40.5 | 45 | 87.8 | 97.5 | 175.5 | 195 | ||
3 | 16-QAM | 1/2 | 26 | 28.9 | 54 | 60 | 117 | 130 | 234 | 260 | ||
4 | 16-QAM | 3/4 | 39 | 43.3 | 81 | 90 | 175.5 | 195 | 351 | 390 | ||
5 | 64-QAM | 2/3 | 52 | 57.8 | 108 | 120 | 234 | 260 | 468 | 520 | ||
6 | 64-QAM | 3/4 | 58.5 | 65 | 121.5 | 135 | 263.3 | 292.5 | 526.5 | 585 | ||
7 | 64-QAM | 5/6 | 65 | 72.2 | 135 | 150 | 292.5 | 325 | 585 | 650 | ||
8 | 256-QAM | 3/4 | 78 | 86.7 | 162 | 180 | 351 | 390 | 702 | 780 | ||
9 | 256-QAM | 5/6 | N/A | N/A | 180 | 200 | 390 | 433.3 | 780 | 866.7 |
Several companies are currently offering 802.11ac chipsets with higher modulation rates: MCS-10 and MCS-11 (1024-QAM), supported by Quantenna and Broadcom. Although technically not part of 802.11ac, these new MCS indices are expected to become official in the 802.11ax standard (2017-2019), the successor to 802.11ac.
Advertised
Type | 2.4 GHz band[lower-alpha 4] (Mbit/s) | 5 GHz band (Mbit/s) |
---|---|---|
AC600 | 150 | 433 |
AC750 | 300 | 433 |
AC1200 | 300 | 867 |
AC1300 | 400 | 867 |
AC1300[9] | - | 1,300 |
AC1450 | 450 | 975 |
AC1600 | 300 | 1,300 |
AC1750 | 450 | 1,300 |
AC1900 | 600[lower-alpha 5] | 1,300 |
AC2200 | 450 | 1,733 |
AC2350 | 600[lower-alpha 5] | 1,733 |
AC2600 | 800 | 1,733 |
AC3100 | 1000 | 2,167 |
AC3150 | 1000 | 2,167 |
AC3200 | 600[lower-alpha 5] | 1,300 + 1,300[lower-alpha 6] |
AC5300[12] | 1000[lower-alpha 7] | 2,166 + 2,166 |
Products
Commercial routers and access points
Quantenna released the first 802.11ac chipset for retail Wi-Fi routers and consumer electronics on November 15, 2011.[13] Redpine Signals released the first low power 802.11ac technology for smartphone application processors on December 14, 2011.[14] On January 5, 2012, Broadcom announced its first 802.11ac Wi-Fi chips and partners[15] and on April 27, 2012, Netgear announced the first Broadcom-enabled router.[16] On May 14, 2012, Buffalo Technology released the world’s first 802.11ac products to market, releasing a wireless router and client bridge adapter.[17] On December 6, 2012, Huawei announced commercial availability of the industry's first enterprise-level 802.11ac Access Point.[18]
Apple Inc. is selling 802.11ac versions of its AirPort Extreme and AirPort Time Capsule products.[19] Motorola Solutions is selling 802.11ac access points including the AP 8232.[20] In April 2014, Hewlett-Packard started selling the HP 560 access point in the controller-based WLAN enterprise market segment.[21]
Commercial laptops
On June 7, 2012, it was reported that ASUS had unveiled its ROG G75VX gaming notebook, which will be the first consumer-oriented notebook to be fully compliant with 802.11ac[22] (albeit in its "draft 2.0" version).
In June 2013, Apple announced that the new MacBook Air features 802.11ac wireless networking capabilities,[23][24] later announcing in October 2013 that the MacBook Pro and Mac Pro also featured 802.11ac.[25][26]
As of December 2013, Hewlett-Packard incorporates 802.11ac compliance in laptop computers.[27]
Commercial handsets
Vendor | Model | Release Date | Chipset | Notes |
---|---|---|---|---|
HTC | One (2013) | February 19, 2013 | BCM4335 [28] | First 802.11ac-enabled handset announced February 19, 2013[29] |
Samsung | Galaxy S4 | April 26, 2013 | BCM4335 [30] | |
Samsung | Galaxy Note 3 | September 25, 2013 | BCM4339 [31] | Subsequent Devices Include 802.11ac |
LG | LG Nexus 5 | October 2013[32] | BCM4339 [33] | BCM4339 is the updated version of the BCM4335 |
Nokia | Lumia 1520 | November 2013[34] | WCN3680 | First 802.11ac-enabled Windows Phone |
Nokia | Lumia Icon | February 20, 2014[35] | WCN3680 | Lumia 930 is Europe version of the same phone, also with 802.11ac |
HTC | One (M8) | March 25, 2014 | WCN3680 [36] | |
Samsung | Galaxy S5 | April 11, 2014 | BCM4354[37] | |
LG | G2 | September 18, 2013 | AWL9581 [38] | |
LG | G3 | May 23, 2014 | BCM4339 [39] | |
Amazon.com | Fire Phone | July 25, 2014 [40] | WCN3680 [41] | |
Samsung | Galaxy S5 Prime/SM-G906S | June 18, 2014 | QCA6174 | |
Samsung | Galaxy Alpha | September 07, 2014 | E702A7[42] | |
Apple | iPhone 6 | September 19, 2014 | BCM4345[43] | First 802.11ac-enabled iOS device, along with iPhone 6 Plus |
Apple | iPhone 6 Plus | September 19, 2014 | BCM4345[43] | First 802.11ac-enabled iOS device, along with iPhone 6 |
Motorola | Nexus 6 | October 16, 2014 | BCM4356[44] | |
Samsung | Galaxy Note 4 | October 10, 2014 | BCM4358[45] | |
Commercial tablets
Vendor | Model | Release Date | Chipset | Notes |
---|---|---|---|---|
Microsoft | Surface Pro 3 | June 20, 2014 | Avastar 88W8897 | 802.11ac-enabled touchscreen computing device |
Apple | iPad Air 2 | October 24, 2014 | Broadcom BCM4350 | First 802.11ac-enabled iOS tablet device |
Nexus 9 | November 3, 2014 | Nvidia Tegra K1 | 2x2 MIMO |
Chipsets
Vendor | Part # | Streams | LDPC | TxBF | 256-QAM | Applications |
---|---|---|---|---|---|---|
Broadcom | BCM43602 | 3 | routers, laptops | |||
Broadcom | BCM4360 | 3 | routers, laptops | |||
Broadcom | BCM43569 | 2 | DTV | |||
Broadcom | BCM4352 | 2 | tablets | |||
Broadcom | BCM4350 | 2 | tablets | |||
Broadcom | BCM4356 | 2 | handsets, tablets | |||
Broadcom | BCM4354 | 2 | handsets, tablets | |||
Broadcom | BCM4339 | 1 | handsets | |||
Broadcom | BCM4335 | 1 | handsets | |||
Marvell | Avastar 88W8897 | 2 | tablets | |||
Marvell | Avastar 88W8864 | 3 | routers | |||
Qualcomm | WCN3680 | 1 | handsets | |||
Qualcomm | QCA9862 | 2 | tablets | |||
Qualcomm | QCA9880 | 3 | home routers | |||
Qualcomm | QCA9890 | 3 | enterprise routers | |||
Qualcomm | QCA9892 | 2 | tablets, PtP Links | |||
Qualcomm | QCA9990 | 4 | enterprise access points | |||
Qualcomm | QCA9992 | 3 | enterprise access points | |||
MediaTek | MT7610 | 1 | ? | ? | ? | PC (PCIe or USB) |
MediaTek | [ MT7650] | 1 | ? | handsets | ||
MediaTek | MT7612E | 2 | laptops (PCIe 2.0) | |||
MediaTek | MT7612U | 2 | laptops (USB 3.0) | |||
Quantenna | QAC2300 | 4 | routers | |||
Redpine Signals | RS9117 | 1 | ? | handsets | ||
Redpine Signals | RS9333 | 3 | ? | routers | ||
Realtek | RTL8811AU | 1 | ? | ? | ? | adapter (USB 2.0) |
Realtek | RTL8812AU | 2 | ? | ? | ? | adapter (USB 3.0) |
See also
Notes
- ↑ A second stream doubles the theoretical data rate, a third one triples it, etc.
- ↑ MCS 9 is not applicable to all channel width/spatial stream combinations.
- ↑ GI stands for the guard interval.
- ↑ 802.11ac only specifies operation in the 5 GHz band. Operation in the 2.4 GHz band is specified by 802.11n.
- 1 2 3 With 802.11n, 600 Mbit/s in the 2.4 GHz band can be achieved by using four spatial streams at 150 Mbit/s each. As of December 2014, commercially available devices that achieve 600 Mbit/s in the 2.4 GHz band use 3 spatial streams at 200 Mbit/s each.[10][11] This requires the use of 256-QAM modulation, which is not compliant with 802.11n and can be considered a proprietary extension.[11]
- ↑ As of December 2014, commercially available AC3200 devices use two separate radios with 1,300 Mbit/s each to achieve 2,600 Mbit/s total in the 5 GHz band.
- ↑ With proprietary extension to 802.11n, using 40MHz channel in 2.4GHz, 400ns guard interval, 1024-QAM, and 4 spatial streams.
References
- 1 2 3 "Official IEEE 802.11 Working Group Project Timelines". 2012-11-03.
- ↑ Kelly, Vivian (2014-01-07). "New IEEE 802.11ac™ Specification Driven by Evolving Market Need for Higher, Multi-User Throughput in Wireless LANs". IEEE. Retrieved 2014-01-11.
- ↑ Kassner, Michael (2013-06-18). "Cheat sheet: What you need to know about 802.11ac". TechRepublic. Retrieved 2013-06-20.
- 1 2 "802.11ac: A Survival Guide". Chimera.labs.oreilly.com. Retrieved 2014-04-17.
- ↑ "Can Single Channel Really Work?". Blog.merunetworks.com. 2013-07-17. Retrieved 2014-04-17.
- ↑ de Vegt, Rolf (2008-11-10). "802.11ac Usage Models Document".
- ↑ "ASUS RT-AC56U & USB-AC56 802.11AC Review". Hardwarecanucks.com. Retrieved 2014-04-24.
- ↑ "IEEE Std 802.11ac™-2013 - 22.5 Parameters for VHT-MCSs" (PDF). IEEE. 2013-12-11. pp. 323–339. Retrieved 2015-04-13.
- ↑ http://www.smallnetbuilder.com/wireless/wireless-reviews/32327-linksys-wumc710-wireless-ac-universal-media-connector-reviewed
- ↑ Ganesh, T S (2014-09-02). "Netgear R7500 Nighthawk X4 Integrates Quantenna 4x4 ac Radio and Qualcomm IPQ8064 SoC". anandtech.com. Retrieved 2014-09-08.
- 1 2 Higgins, Tim (2013-10-08). "AC1900: Innovation or 3D Wi-Fi?". smallnetbuilder.com. Retrieved 2014-09-08.
- ↑ http://www.cnet.com/products/netgear-r8500-nighthawk-x8-ac5300-smart-wifi-router/#!
- ↑ "Quantenna Launches World's First 802.11ac Gigabit-Wireless Solution for Retail Wi-Fi Routers and Consumer Electronics" (Press release). Quantenna. 2011-11-15.
- ↑ "Redpine Signals Releases First Ultra Low Power 802.11ac Technology for Smartphone Application Processors" (Press release). Redpine Signals. 2011-12-14. Retrieved 2013-03-15.
- ↑ "Broadcom Launches First Gigabit Speed 802.11ac Chips - Opens 2012 CES with 5th Generation (5G) Wi-Fi Breakthrough" (Press release). Broadcom. 2012-01-05. Retrieved 2013-03-15.
- ↑ "Netgear's R6300 router is first to use Broadcom 802.11ac chipset, will ship next month for $200". Engadget. Retrieved 10 September 2014.
- ↑ "Buffalo's 802.11ac Wireless Solutions Available Now" (Press release). Austin, Texas: Buffalo Technology (via PRNewswire). May 14, 2012. Retrieved 2013-03-15.
- ↑ "Huawei Announces Commercial Availability of Industry’s First Enterprise-level 802.11ac Access Point". Huawei. 6 December 2012.
- ↑ "Apple - Mac - Airport Express". Retrieved 10 September 2014.
- ↑ AP 8232 Modular 802.11n Access Point - Motorola Solutions USA
- ↑ "HP Launches the HP 560 802.11ac Access Point". HP. 2014-03-31.
- ↑ "Asus gaming notebook first to feature full 802.11ac". Electronista. 2012-06-07. Retrieved 2013-03-15.
- ↑ "Apple unveils new MacBook Air lineup with all-day battery life, 802.11ac Wi-Fi". AppleInsider. 2013-06-11. Retrieved 2013-06-11.
- ↑ "Apple - Macbook Air". Retrieved 10 September 2014.
- ↑ "MacBook Pro with Retina display - Technical Specifications". Apple. Retrieved 10 January 2014.
- ↑ "Mac Pro - Technical Specifications". Apple. Retrieved 10 January 2014.
- ↑ "HP ENVY TouchSmart 17-j043cl Notebook PC Product Specifications HP ENVY TouchSmart 17-j043cl Notebook PC | HP Support". H10025.www1.hp.com. Retrieved 2014-04-17.
- ↑ "BCM4335".
- ↑ "HTC One specs".
- ↑ "BCM4335".
- ↑ "Samsung Galaxy Note 3 Review".
- ↑ "LG Nexus 5".
- ↑ "iFixIt Nexus 5 Teardown".
- ↑ "Nokia Lumia 1520". Nokia. Retrieved 2014-11-10.
- ↑ "Nokia Lumia Icon". Nokia. Retrieved 2014-11-10.
- ↑ "HTC One(M8) Teardown".
- ↑ "Samsung Galaxy S5 Hits Stores, Chock Full of Broadcom Tech".
- ↑ http://www.anadigics.com/news/press_releases/lg_electronics_g2_powered_anadigics_80211ac_wifi_feic/. Missing or empty
|title=
(help) - ↑ "LG G3 Teardown".
- ↑ "Amazon Fire Phone".
- ↑ "Amazon Fire Phone Teardown".
- ↑ "Samsung Galaxy Note 4 & Galaxy Alpha".
- 1 2 "Apple iPhone 6 Teardown".
- ↑ "Nexus 6 Teardown".
- ↑ "Samsung Galaxy Note 4 Review".
External links
- 802.11ac Technology Introduction white paper
- A brief technology introduction on the 802.11ac amendment to the 802.11-2007 standard
- A list of 802.11ac devices
- The Not So Definitive Guide to Beamforming
- Understanding IEEE 802.11ac Wi-Fi Standard and Preparing the Enterprise WLAN
- MIMO 802.11ac Test Architectures
- 802.11ac: The Fifth Generation of Wi-Fi Technical Paper
|