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Close Proximity and Short Range Wireless Personal Area Networks

A quick overview

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• Close Proximityo < 1 feet

• Short Range Directional Antennaso Restricted to within one device within a room

• Wireless Video Access Networkso Image, Audio, Videoo Interactive Multimedia

• Various open standards and atleast one proprietary format:o WirelessHDo Ultra Wide Band (UWB) – IEEE® 802.15.3ao Sony® TransferJet™o IEEE® 802.11no ZigBee – IEEE® 802.15.4o Bluetooth™ SIG/IEEE® 802.15.1

Agenda

Unlicensed radio (60 GHz)

Wireless USB

Cable Free USB

Wireless HDMI

Open standards; “Short Range”Proprietary; “Close Proximity”

PtP

PtMP

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Agenda

• Network topologies, Systems• RF bandwidth allocations

o Licensed vs. unlicensed spectrum• PHY and MAC layer specifications• IPR, Regulatory and Copyright concerns

o MPAA – copyright infringemento FCC/OfCom – interference and power management

• Trade and Industry forumso WiMedia Allianceo UWB Forumo WirelessHD Forumo Sony®o IEEE® 802.11 WGo IEEE® 802.15 WG

• Applicationso HDTVo HD Audioo IPTV

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Communication range

• Wide Area Networkso The Internet!!

• Regional Area Networkso Completely wirelesso ~ 40 km rangeo Backhaul to a WAN

• Metropolitan Area Networkso Wired or Wirelesso Covers several blocks to the entire city (< 50 km)

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Communication range

• Local Area Networkso WLAN – IEEE802.11xo Scalable from enterprise to SOHO

• Personal Area Networkso Connects office and home applianceso < 10 m rangeo Multiple standards for different app scenarioso All built around the concept of a PICONET

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Piconets

• Concept born out of IEEE 802.15• Can be used to explain any “pico” network

topology• One DEVice masquerades as a PicoNet Controller

(PNC) (master)• Several (slave) DEVices

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IEEE 802.15.3 PHY

• 2.4 – 2.4835 GHz carrier frequency (EU, Japan, Canada and the US)

• 5 channels (2.412 GHz – 2.462 GHz center frequencies)

• Compatibility with Wi-Fi (IEEE 802.11b) channel assignments

• Multiple timing parameters to allow all DEVs to access all 5 channels

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IEEE 802.15.3 PHY

• Contention based Access Controlo A Contention Access Period (CAP) is specifiedo CSMA/CA protocol is usedo Clear Channel Assessment (CCA)

• Channel Time Access Period (CTAP) channel accesso A fixed Channel Time Allocation (CTA) per DEVo Better power saving and QoSo CTA assignment may be dynamico TDMA based

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IEEE 802.15.3 MAC

• Goalso Fast connection timeo Ad Hoc connectivity

Peer discoveryo Data transport with QoSo Securityo Dynamic membershipo Efficient data transfer

• Superframe sizes range from 64 to 2048 bytes

• CRC-16 error correction

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DEVs and PNCs

• Devices are either master or slaveo Choice is based on capabilitieso Only master devices can become PNCs

• Independent and Dependent piconetso Each has a unique ID

• Dependent piconets = Child or Neighbor

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Piconet hierarchy

• Child piconetso Offload some of the computational and memory

requirements from the parento Extend reacho Operating on different carrier frequencieso DEVs in child piconets are peer to DEVs in parent

piconets• Neighbor piconets

o Sharing carrier frequencies when no more free channels are available

o DEVs in neighboring piconets cannot talk to one another

• One parent may have several child and neighbor piconets connected to it

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Piconet operation

• Top level overviewo Starting a piconeto Creating a child/neighbor piconeto Handing over controlo Association and Disassociation of DEVso Securityo Ending a piconet

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Starting a piconet

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Starting a piconet

• Scan all frequencies• If unused channel is found

o Wait for t = CAPo Transmit beacon

• If no unused channel is foundo Designated PNC may start a dependent piconet

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Handover

• PNC Handover Request command• Any capable DEV may become PNC• If a “more capable” DEV enters a piconet,

PNC handover takes place• In an iterative fashion, the “most

capable” DEV in a piconet MAY assume the role of a PNC

• Handovers may also happen when the current PNC leaves the piconet

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DEV association

DEVIDPiconet servicesDEV services

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• PNC Shutdown Info Element sent

Ending a piconet

PNC Shutdown PNC Shutdown

PNC ShutdownPNC Shutdown

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HDTV

• High Definition Television• 1080 pixels across

o Progressive scanning• 24 bits per pixel for color• Aspect ratio of 16:9• Extra picture content and 5:1 stereo audio

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IEEE 802.15.3x

• Older standard (2003) is called IEEE 802.15.3-2003o Certified by IEEE and WiMedia Alliance

• Specifies only PHY and MAC – no higher layer services explicitly specifiedo May be used as MAC/PHY spec for Bluetooth 3.0,

for e.g.• IEEE 802.15.3”a” is a newer follow-up

o Based on Ultra-wideband (UWB) techniqueso Utilizes Multiband OFDM (MB-OFDM)o To be certified by IEEE, MB-OFDM Alliance and

ECMA

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Common Platform

IEEE 802.15.3x Architecture

IEEE 802.15.3a UWB PHY

IEEE 802.15.3 UWB MAC

Convergence Layer

Wireless USB

Bluetooth 3.0

Non IP P2P (Wireless Firewire)IP (UPnP)

IEEE/MB-OFDM

Alliance

WiMedia Alliance

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Ultra Wide Band (UWB)

• Also known as impulse radio, baseband or Zero-carrier technologyo No upconversion to IF/RF required

• UWB transmits in the form of “extremely short” pulseso Typical pulse durations range from 10 picosec to

1 nanosec• Typical bandwidth of 1.5 to 7 GHz (or

more!!!)• Signals are transmitted slightly over the

noise floor, No• Power Spectral Density (Transmit power

per unit Hz transmitted frequency) is in the order of picoWatts

• Total power over the entire band is in the order of milliWatts

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UWB

2 5 10 f (GHz)

PSD (Watts/Hz)

Noise Floor

WLAN IEEE

802.11aUMTS 3GPP UWB

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UWB

• Advantageso Unlicensed operationo Simplicity due to baseband transmissiono Information is sent using Pulse Position

Modulationo Very low transmit powero Interference immunityo Very high tolerance to multipatho Data rates in the order of 100 Mbpso Scales well with semiconductor technology

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WirelessHD

• Specification finalized in October 2007• Wireless High Definition

o HDTV requires 33% higher data rates than SDTVo Compressed video and audio using MPEG and

H.264/AVCo Advanced device and audio/video control

protocolo Unlicensed operationo Data privacy for user generated contento LOS antenna to ensure P2P

• Operates around the 60 GHz bando Bandwidth of 7 GHz

• Transmit power of not more than 10 W• Reach of ~ 10 m

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WirelessHD

• 2 modes of operationo High Rate WiHDo Low Rate WiHD

• Explicit Feedback Beam Forming• Implicit Feedback Beam Forming

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Wireless USB

• Universal Serial Bus• First drafted in May 2007• Uses the MB-OFDM UWB spec. (IEEE

802.15.3a)• Data rates of 53.3, 106.7, 200 Mbps

mandatoryo Optional data rates of 80, 160, 320, 400 and 480

Mbps• Independent power management• Uses a polled TDMA protocol

o Token, data and handshake packets• Supported by Agere, HP, Intel, Microsoft,

NEC, Philips and Samsung

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Wireless USB

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Wireless HDMI

• High Definition Multimedia Interfaceo Wired

• ~ 65 Mbps throughput• 30 feet LOS• 3.1 to 4.8 GHz carrier• Supports 720p and 1080i HDTV• Utilizes lossless compression based on

JPEG2000 for each frame of video

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TransferJet

• Sony Corporation’s answer to Wireless USB

• Truly “Close Proximity”o < 3 inches

• 4.48 GHz carrier• Upto 375 Mbps throughput

o A maximum of 560 Mbps, including PHY layer error correction and other protocol overheads

• Antenna based on Electric Induction Field Couplingo “Touch and Get”

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Thank You