Thursday, May 7, 2009

WiGig Unites 60 GHz Wireless Development

The Wireless Gigabit Alliance (WiGig) brings together 17 tech firms for 60 GHz streaming video, LAN standards: The 60 GHz unlicensed band, available for use in various forms worldwide, can carry Gbps of data, but there hasn't been unity about how to proceed. The new WiGig group will focus on streaming video (SiBeam is the leader in this band already), wireless LAN (the IEEE already has a 60 GHz working group underway), and docking/synchronization--a replacement for UWB, which hasn't lit up the market yet, but is at least available right now.

Multi-Gbps wireless LAN networking would be a hoot in the home, especially as we push data to networked storage devices and move ever-larger video and photo files around, but the standard's real potential is in providing for lossless high-definition streaming alongside these other purposes.

The group has been working together for a year, and chose this moment to makes its public debut. A standard is due out in fourth quarter, with testing to follow. WiGig intends to bring its work to the IEEE group on 60 GHz wireless LAN (802.11ad), and many WiGig members are also Wi-Fi Alliance members and IEEE participants. It's possible that 802.11ad will look a lot or entirely like WiGig. WiGig will also create a testing plan and carry out certification.

Bill McFarland, chief technical officer at Atheros, said in an interview today that it's clear consumers will wind up moving increasingly more data around the home. "People will end up with large files and high data rate streams. They're going to want to be able to move it flexibly," he said. Rather than have multiple chips dedicated to different purposes, WiGig is trying to unite it all under one banner.

McFarland noted that 60 GHz has a big advantage: 7 GHz of available in the U.S. and much of the world. "This very broad piece of bandwidth that we can use without licenses, without paying, and it allows us to use it in kind of big chunks, where we can get to very high data rates"--multiple gigabits per second.

The high data rates allow uncompressed HD video--roughly 3 Gbps--which avoids the current expense, possible image degradation, and latency of adding H.264 chips or other compression hardware between the transmitter and receiver.

The WiGig group isn't intending its standard as a Wi-Fi competitor; 60 GHz attenuates rapidly and doesn't penetrate objects well. This limits it to mostly in-room purposes. Wi-Fi in 802.11n can work well throughout a house. The idea of tri-band (2.4/5/60 GHz) chips seems like a reasonable path to take.

I asked McFarland how this 60 GHz effort would avoid the pitfalls of ultrawideband's rocky 7-year road to potential oblivion. He noted that there's no other spectrum available that enables multiple Gbps, and that by bringing together a set of companies involved through the development and marketing chain they can avoid the strife that delayed and may have doomed UWB.

When UWB was initially proposed, the FCC hadn't approved it. Ultimately, regulators worldwide allow UWB, but some have highly restricted the spectrum range, which reduces the number of simultaneous networks and devices, and requires more flexibility in product design. The 60 GHz effort starts with worldwide regulation already in place.

Ultimately, UWB took so long from design to market that "the data rates that UWB offered were not significantly higher than what could be achieved using 11n technology, so there was no strong, compulsive drive" to put UWB in hardware. (UWB started to make noise when Wi-Fi's highest rate was 11 Mbps, remember.)

Mark Grodzinsky, the marketing vice president of startup Wilocity, a firm that will develop chips and reference (and someone who was deeply involved in reconciling 802.11n into a viable standard), said of the 13 firms on the board of directors, "This is a group of companies that really knows how to do this and has done it before very well." Combined, they sell billions of wireless chips each year.

The intent with WiGig is to have several key differentiators that make the technology have multiple factors that can't be achieved with anything today, and that aren't likely to be achieved by any other technology the drawing board. This includes the high speed, but also the notion of multiple applications using a single radio. (This is how Bluetooth has managed to thrive, and it was one of the intents of the WiMedia Alliance for UWB.)

Grodzinsky described wireless docking and wireless display as two capabilities that are highly limited with any technology today. If you have a device capable of eSATA, gigabit Ethernet, and multiple USB streams, but the dock connection is 480 Mbps USB 2.0 or even wireless USB, performance is highly throttled down. A wireless display isn't really possible.

WiGig was also conceived with handheld devices front and center: characteristics that keep power use low are part of the spec from the get-go. Grodzinsky said, for instance, that error correction schemes are only used if errors need to be corrected; other wireless burn cycles on fixing errors when they don't exist.

WiGig's board of directors includes major chipmakers in the wireless space (Atheros, Broadcom, Intel, and Marvell), handset firms (LG, Nokia, and Samsung), PC-focused companies (Dell, Intel, and Microsoft), and consumer electronics manufacturers (NEC, Panasonic, and Samsung). Note there's some overlap among those firms' markets, too. Notably absent is Apple, which rarely joins standards groups at their inception, but is often an early adopter and later board member. Sony is also missing from this list. (Four other firms are "contributors" and not on the board, including more chipmakers.)

SiBeam is also not on the list, although its backers Panasonic and Samsung are. SiBeam is part of the WirelessHD Consortium, which is backed by six firms in the WiGig group, plus Sony and Toshiba. There will have to be a merger or some kind of close association between WirelessHD and WiGig because no TV set or computer will have two sets of chips, and WirelessHD doesn't have a data-transfer focus.