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In May, fifteen technology companies joined to form the Wireless Gigabit (WiGig) Alliance with the goal of establishing a unified specification for 60 Gigahertz (GHz) wireless technologies. The newly formed WiGig Alliance hopes to spur the development of a wide variety of consumer devices that would be capable of sending high definition (HD) programming, data and other content over 60 Gigahertz (GHz) spectrum at speeds 10 times faster than current wireless networks. The alliance envisions a global wireless ecosystem of interoperable, high performance devices that work together seamlessly to connect people in the digital age. The technology will enable multi-gigabit-speed wireless communications among these devices and will help the industry convergence to a single radio using the readily available, unlicensed 60 GHz spectrum.
According to the alliance officials, the WiGig specification will allow devices to communicate without wires at gigabit speeds within a typical room. The group's vision is to create a global ecosystem of interoperable products based on this specification, which will unify the next generation of entertainment, computing and communications devices. The member companies are leaders in the wireless, CE, PC and handheld markets and have the technical acumen and business experience to make the 60 GHz wireless technology a reality for both the home and enterprise. "To help bring this technology to market, we welcome new member companies to join our group", said Dr. Ali Sadri, President and Chairman of the Wireless Gigabit Alliance. Among the companies that comprise the board of directors for the alliance are Atheros Communications, Broadcom Corp., Dell, Intel Corp., LG Electronics, Marvell International., MediaTek, Microsoft Corp., NEC Corp., Nokia Corp., Panasonic Corp., Samsung Electronics Co. and Wilocity.
The WiGig specification is expected to be available to member companies in Q4 of 2009. If WiGig Alliance can complete its so-called WiGig Specification this year, the group hopes to put together an infrastructure to test and certify devices by the second half of 2010. That means consumer products using its 60 GHz technologies won't hit the market until the latter part of 2010 or 2011.
Two other groups already touting competing technologies for the wireless transmission of high-definition content in the home include the WirelessHD Consortium and the Wireless Home Digital Interface (WHDI). While high-speed wireless technologies have attracted a lot of interest, it is too early to say which of the competing groups and technologies is likely to triumph. Some major manufacturers appear to have hedged their bets by joining more than one group. Samsung, for example, is a member of all three groups.
WHDI, which claims to be the furthest along in bringing products to the market, uses the unlicensed 5-GHz spectrum. Signals sent over the 5-GHz spectrum travel further than signals sent over 60 GHz, which are generally limited in range to one room. As a result, the WHDI solution is capable of sending HD content throughout the home. But the bandwidth limitations of the 5-GHz spectrum mean it can't transmit all the bits that make up the HD stream.
The requirement for high data throughput at distances of 10 meters requires a large allocated frequency spectrum. Like the WiGig Alliance, the competing WirelessHD Consortium also uses the 60 GHz spectrum, which allows uncompressed HD content to be transmitted between TVs, set-top boxes and other devices at very high data rates. The WirelessHD specification defines a wireless video area network (WVAN) for the connection of consumer electronic (CE) audio and video devices. A key attribute of the WirelessHD system is its ability to support the wireless transport of an uncompressed 1080p A/V stream with a high quality of service (QoS) within a room at distances of ten meters.
In North America and Japan, the WirelessHD specification allocates a total of 7 GHz for use, 5 GHz of which is overlapping. The band 57~64 GHz is allocated in North America while 59-66 GHz is allocated in Japan. In addition, Korea and the European Union have also allowed similar allocations. The regulator agencies allow very high effective transmit power (the combination of transmitter power and antenna gain), greater than 10 W of effective isotropic radiated power (EIRP). High EIRP and wide allocated bandwidth will allow high throughput connections that, however, are very directional.
The WirelessHD specification defines a novel wireless protocol that enables directional connections that adapt very rapidly to changes in the environment. This is accomplished by dynamically steering the antenna beam at the transmitter while at the same time focusing the receiver antenna in the direction of the incoming power from the transmitter. This dynamic beam forming and beam steering utilizes not only the direct path, but allows the use of reflections and other indirect paths when the line-of-sight connection is obstructed. This dynamic adjustment of the antenna energy is completed in less than one millisecond.
The WirelessHD Consortium has been very focused on removing the HDMI cable but they haven't focused on IP-networking or on servicing multiple devices. Mark Grodzinsky, chair of the marketing working group for the new WiGig Alliance and vice president of marketing for member company Wilocity commented that, "While streaming uncompressed video is very important for the WiGig alliance, it is equally important that we have technology to serve all these platforms. That is how I would differentiate our group."
The group, targeting a broad range of wireless applications ranging from home nets to mobile phones, is working on a specification for 60 GHz networking at rates up to 6 Gbits/second. Because of the limited range inherent in high frequency technologies, WiGig will presumably be an in-room technology, although they claim they wish to connect devices wirelessly throughout the home. 60 GHz simply does not currently have the range to achieve whole-home transmission, and using WiGig technology alone to accomplish this will be a Herculean task, likely requiring the use of some type of repeater technology in the home. "If the plan is to create a whole-home network with a combination of 60 GHz and Wi-Fi, it seems more likely to succeed, and perhaps explains the presence of Wi-Fi chip vendors in the Alliance.
Many observers anticipate 60-GHz products that also will include 2.4- and 5-GHz Wi-Fi.
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