that does what Wi-Fi does, but better: A secure, short-range, high-bandwidth wireless protocol for home use. Thats what the Wireless Gigabit Alliance (or WiGig) started looking into about five years ago. WiGigs specifications provide for an in-Presented by: home wireless system like Wi-Fi that goes far faster, can handle more devices with less BIBI ABIDA interference, is more secure, and uses less power (handy on ever more power-hungry mobile phones). This is due to the use of the 60-gigahertzWi-Gig band of radio spectrum. The reasons why are complicated and technical, but the 60-GHzFrustrated by unsecured Wi-Fi, a fix is on band is sort of like a brand new highwaythe way…. compared with the retrofitted roads of todays Wi-Fi devices. They can carve upABSTRACT the spectrum better, design the devices with more advanced features, and generally fulfillThe widespread availability and use of the needs of a modern wireless devicedigital multimedia content has created a better.need for faster wireless connectivity thatcurrent commercial standards cannot The WiGig 1.0 standard combines twosupport. This has driven demand for a single different wireless technologies: 60-gigahertzstandard that can support advanced wireless and Wi-Fi. The first technologyapplications such as wireless display and uses the 60-gigahertz band of the wirelessdocking, as well as more established usages spectrum to create a 10-meter range wirelesssuch as network access. network. It also uses ―Beamforming‖ to extend the range of the 60-gigahertz networkWi-Fi is so common and used by so many beyond 10 meters. The 60-gigahertz wirelessdevices that its starting to become a network can support devices inside a roomproblem. Within the bands of radio spectrum and can transfer data at 7 gigabits percarved out for Wi-Fi communication, there second, or about 10 times faster than theare only so many channels and frequencies fastest Wi-Fi networking available.that devices can connect over. This leads tointerference, low speeds, and droppedsignals.Just ask anyone whos ever been in a roomwith a couple hundred Wi-Fi devices —getting and keeping a signal can be difficult.Even Steve Jobs had a demo fail on stagebecause of how dense the air was with Wi-Ficommunications.So the pressure is on to find a replacement
Introduction computers and handheld devices. For the first time, consumers will be able to create aThe widespread availability and use of complete computing and consumerdigital multimedia content has created a electronics experience without wires.need for faster wireless connectivity that Specification Overviewcurrent commercial standards cannotsupport. This has driven demand for a single The WiGig specification includes keystandard that can support advanced features to maximize performance, minimizeapplications such as wireless display and implementation complexity and cost, enabledocking, as well as more established usages compatibility with existing Wi-Fi andsuch as network access. provide advanced security. Key features include:The Wireless Gigabit (WiGig) Alliance wasformed to meet this need by establishing a Support for data transmission ratesunified specification for wireless up to 7 Gbps; all devices based oncommunication at multi-gigabit speeds; this the WiGig specification will bespecification is designed to drive a global capable of gigabit data transfer rates.ecosystem of interoperable products. Designed from the ground up toThe WiGig MAC and PHY Specification support low-power handheld devicesenables data rates up to 7 Gbps, more than such as cell phones, as well as high-10 times the speed of the fastest Wi-Fi performance devices such asnetworks based on IEEE 802.11n. It computers; includes advanced poweroperates in the unlicensed 60 GHz frequency management.band, which has much more spectrum Support for beamforming,available than the 2.4 GHz and 5 GHz maximizing signal strength andbands used by existing Wi-Fi products. This enabling robust communication atallows wider channels that support faster distances beyond 10 meters.transmission speeds. Widely used advanced security andThe WiGig specification is based on the power management for WiGigexisting IEEE 802.11 standard, which is at devices.the core of hundreds of millions of Wi-Fi Physical layer enables low powerproducts deployed worldwide. and high performance WiGigThe specification enables a broad range of devices, guaranteeingadvanced uses, including wireless docking interoperability and communicationand connection to displays, as well as at gigabit rates.virtually instantaneous wireless backups, Supplements and extends the 802.11synchronization and file transfers between Media Access Control (MAC) layer.
StructureThe WiGig specification defines Physical(PHY) and Medium Access Control (MAC)layers and is based on IEEE 802.11. Thisenables native support for IP networkingover 60 GHz. It also makes it simpler andless expensive to produce devices that cancommunicate over both WiGig and existingWi-Fi using tri-band radios (2.4 GHz, 5GHz and 60 GHz). Figure 2. WiGig Protocol Adaptation Layers (PALs) 1.Physical layer (PHY) Like the 2.4 GHz and 5 GHz bands used by Wi-Fi, the 60 GHz band used by WiGig is unlicensed and available worldwide. Because the 60 GHz band has much more spectrum available, the channels are much wider, enabling multi- gigabit data rates. The WiGig specification defines four channels, each 2.16 GHz wide – 50 times wider than the channels available in 802.11n.These wide channels enableFigure 1. WiGig architecture enables tri-band WiGig to support applications that requirecommunications extremely fast communication, such asThe WiGig Alliance is also defining uncompressed video transmission.Protocol Adaptation Layers (PALs) thatsupport specific data anddisplay standards Modulation and Coding Schemes(MCS)over 60 GHz. PALs allow wireless The specification supports two types ofimplementations of these standard interfaces modulation andthat run directly on the WiGig MAC and coding schemes, which provide differentPHY, as shown in Figure benefits:2, and can be implemented in hardware. The Orthogonal frequency-divisioninitial PALs are audio-visual (A/V), which multiplexing (OFDM) supportsdefines support for HDMI and DisplayPort, communication over longerand input-output (I/O), which defines distanceswith greater delay spreads,support for USB and PCIe. providing more flexibility in handling obstacles and reflected
signals. Furthermore, OFDM allows Power Management the greatest transmission speeds of WiGig devices can take advantage of a new up to 7 Gbps. scheduledaccess mode to reduce power Single carrier (SC) typically results consumption. Two devices communicating in lower powerconsumption, so it is with each other via a directional link may often a better fit for small, low- schedule the periods during which they power handheld devices. SC communicate; in between those periods, supports transmission speeds up to they can sleep to save power. This advanced 4.6 Gbps. capability allows devicesto more precisely tailor their power management to their2.Medium Access Control (MAC) Layer actual traffic workload, and is especially important for cell phones and other handheldThe MAC layer of the WiGig specification battery-powered devices.includes new features that support advancedusage models, facilitate integration with 3.Protocol Adaptation Layers (PALs)Wi-Fi networks, reduce power consumption PALs allow wireless implementations of keyand provide strong security. computerand consumer electronicsWi-Gig Beamforming interfaces over 60 GHz WiGig networks. PALs make it easier for implementers toUse of the 60 GHz band allows extremely produce devices with built-in support forfast communication, but also presents the specific uses such as wireless connections tochallenge that propagation loss is higher displays. PALs enable highly efficientthan in the 2.4 GHz and 5 GHz bands. The implementations because they are definedWiGig specification addresses this challenge directly on the WiGig MAC and PHY,using adaptive beamforming, a technique rather than layered on other protocols andthat enables robust multi-gigabit can be implemented in hardware. Thiscommunications at distances greater than 10 maximizes performance and reduces powermeters. Beamforming employs directional consumption.antennas to reduce interference and focus Audio-Visual (A/V)the signal between two devices into a The A/V PAL allows wireless transmissionconcentrated ―beam.‖ This allows faster data of audio-visual data. An example might betransmission over longer distances. transmitting movies from a computer or digital camera to a TV set or projector. This PAL supports wireless implementations of HDMI and Display Port interfaces, as well as the High-bandwidth Digital Content Protection (HDCP)scheme used to protect digital content transmitted over those interfaces. It scales to allow transmission of both compressed and uncompressed video.
Input-Output (I/O)The I/O PAL defines high-performancewireless implementations of widely usedcomputer interfaces over 60 GHz.ConclusionThe WiGig Alliance is also specifyingPALs that define wireless implementationsof A/V and I/O interfaces, facilitatingadvanced applications such as wirelessdocking, high-speed synchronization andconnection to displays.The publication ofthe specification enables manufacturers tocreate a global ecosystem of interoperableWiGig products. Now, the specification isavailable to members of the WiGig Alliance,who are able to develop next-generationwireless products under royalty-free terms.In future, we will find people switching toWi-Gig.References 1. http://en.wikipedia.org/wiki/Wireless _Gigabit_Alliance 2. http://www.engadget.com/2009/12/1 0/wigig-alliance-completes-multi- gigabit-60ghz-wireless-specificat/ 3. http://www.businesswire.com/portal/ site/home/permalink/?ndmViewId=n ews_view&newsId=2009121000511 1&newsLang=en