Will 802.11af WiFi Replace 802.11ac in the Home?
/802.22, WRAN, Wi-FAR, 802.11af, White-Fi, 802.19.1, Super-WiFi. What they have in common? They all are part of the newest IEEE standards ecosystem supporting spectrum sharing for cloud-directed agile radios. TV White Spaces or TVWS was the first brand used for the spectrum sharing method adopted by the FCC in 2010. Now, new spectrum sharing terms are being adopted like “dynamic spectrum access” and “spectrum access system.” Spectrum sharing is also moving out of the spectrum occupied by TV stations and into 3.5GHz, so “TV” and “White Spaces” may no longer be
applicable descriptors. With the new IEEE 802.xx standards being approved for the new spectrum sharing radios, chip makers are looking at committing the multi-million dollar budget required for manufacturing a chip. After the chip makers start delivering the chips to the world, the new efficient spectrum sharing system will be known by the industry with the IEEE designation: 802.22 for long-haul broadband or 802.11af for local area WiFi broadband.
2011. WRAN = 802.22. On July 1, 2011, IEEE published 802.22. Dubbed, Wireless Regional Area Networks (WRAN) it is also known as W-FAR, a better descriptor. Dr. Apurva Mody led the IEEE 802.22 Working Group. Dr. Mody also is the Chairman of the White Space Alliance. He and the other White Space Alliance members such as iConectiv have tirelessly promoted the spectrum sharing method across the globe.
Why is 802.22 a big deal? The industry press focuses on WRAN’s a big mileage broadband reach of 20-60 miles. The service can deliver 22Mbps over a 6MHz channel and can technically combine 4 channels to deliver up to 88 Mbps. The spectrum for 802.22 standard is the unused TV channels ranging from 54MHz (VHF Channel 2) to 862MHz (TV channel 69). The unused spectrum is called “White Spaces,” located between active TV channels. What is new and unique technically about 802.22 is that it establishes a method for more efficiently employing the empty TV channel spectrum and not interfering with active TV spectrum. The cloud database “directs” the spectrum agile broadband radios to use free TV channels based on information received from spectrum regulator like the FCC. 802.22 provides for different power levels as authorized by the regulator. For fixed-outdoor uses, the maximum power is allowed by the FCC is 4 Watts but
for personal portable agile radios it is 100mW. It is the 4 Watt power that allows 802.22 devices to deliver fixed, wireless broadband through 25 miles of trees, just like TV stations and 2-way public safety radios.
The applications are endless as the 802.22 fixed wireless broadband radios can potentially eliminate the use of towers because of the superior propagation characteristics through trees, buildings, and terrain. The radios can deliver intelligent transportation system (ITS) applications through curves and trees found in thousands of miles of roads. 802.22 can
deliver fixed broadband for mobile carrier backhaul in rural areas and to carrier small cells in urban areas. The TV White Spaces radios can also deliver fixed wireless broadband across hundreds of miles of rural areas, through trees and terrain in Africa, India, and Asia where there is no fiber.
White-Fi or 802.11af. On February 25, 2014, IEEE took another significant step publishing 802.11af, also called White-Fi. Bruce Kraemer, is the Chair of 802.11 and works at Marvell Semiconductor. 802.11af is a modified WiFi standard building on the 802.11ac WiFi. 802.11af WiFi operates with spectrum sharing techniques using a “cloud” geo-location database in the TV channel spectrum with agile radios. 802.11af allows radios to use 6, 7, and 8 MHz channels bonded up to 4 channels delivering 24-32MHz of spectrum. 802.11af is meant for short-range broadband connections, and not for 802.22 long-haul connections. This means that 802.11af will be ideal for M2M connections as it will use well-known 802.11ac methods but, using the TV spectrum, will penetrate walls, basements, and foliage. WiFi using 2.4GHz, on the other hand, cannot reach into many home basements and is difficult to consistently connect M2M devices.
2014. IEEE 802.19.1 On September 17, 2014, IEEE moved again and published 802.19.1. It established “co-existence” standards for agile radios operating together within the unlicensed spectrum directed by geo-location cloud databases. Steve Shellhammer, is the chair of the IEEE 802.19 Wireless Coexistence Working Group, and is a senior manager at Qualcomm. 802.19 requires a coexistence and information server which gathers information regarding the location, antenna height, and power levels of other nearby agile radio networks operating in approved unlicensed
spectrum slices. With the notification information from the coexistence servers, the agile radio networks can move to nearby other lesser-used unlicensed channels. The 802.11af and 802.22 standards focus on preventing interference with active TV spectrum but not between the agile radios themselves.
On the Starting Line: Chip Makers. 802.22 and 802.11af standards, or chips, are not yet operating in the agile spectrum sharing radios. The large chip makers, like Qualcomm, Hitachi, MediaTek, and Broadcom, have been looking at this market carefully. Some announced, at the August 2014 Global Spectrum Sharing Summit in Las Vegas, that they are looking very closely at 802.22 and 802.11af chip market. Because building a chip requires millions of dollars to tool and manufacture, the question is which of chip manufacturers will start manufacturing first, leaving the others far behind.
When chips start coming off the line, White-Fi will replace 802.11ac 2.4GHz. Why? 802.11af will deliver broadband into the back rooms of my house and into the basement.
