2. 2 11/24/2008
• Close Proximity
o < 1 feet
• Short Range Directional Antennas
o Restricted to within one device within a room
• Wireless Video Access Networks
o Image, Audio, Video
o Interactive Multimedia
• Various open standards and atleast one proprietary
format:
o WirelessHD
o Ultra Wide Band (UWB) – IEEE® 802.15.3a
o Sony® TransferJet™
o IEEE® 802.11n
o ZigBee – IEEE® 802.15.4
o 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
3. 3 11/24/2008
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 infringement
o FCC/OfCom – interference and power management
• Trade and Industry forums
o WiMedia Alliance
o UWB Forum
o WirelessHD Forum
o Sony®
o IEEE® 802.11 WG
o IEEE® 802.15 WG
• Applications
o HDTV
o HD Audio
o IPTV
4. 4 11/24/2008
Communication range
• Wide Area Networks
o The Internet!!
• Regional Area Networks
o Completely wireless
o ~ 40 km range
o Backhaul to a WAN
• Metropolitan Area Networks
o Wired or Wireless
o Covers several blocks to the entire city (< 50 km)
5. 5 11/24/2008
Communication range
• Local Area Networks
o WLAN – IEEE802.11x
o Scalable from enterprise to SOHO
• Personal Area Networks
o Connects office and home appliances
o < 10 m range
o Multiple standards for different app scenarios
o All built around the concept of a PICONET
6. 6 11/24/2008
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
7. 7 11/24/2008
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
8. 8 11/24/2008
IEEE 802.15.3 PHY
• Contention based Access Control
o A Contention Access Period (CAP) is specified
o CSMA/CA protocol is used
o Clear Channel Assessment (CCA)
• Channel Time Access Period (CTAP) channel
access
o A fixed Channel Time Allocation (CTA) per DEV
o Better power saving and QoS
o CTA assignment may be dynamic
o TDMA based
9. 9 11/24/2008
IEEE 802.15.3 MAC
• Goals
o Fast connection time
o Ad Hoc connectivity
Peer discovery
o Data transport with QoS
o Security
o Dynamic membership
o Efficient data transfer
• Superframe sizes range from 64 to 2048
bytes
• CRC-16 error correction
10. 10 11/24/2008
DEVs and PNCs
• Devices are either master or slave
o Choice is based on capabilities
o Only master devices can become PNCs
• Independent and Dependent piconets
o Each has a unique ID
• Dependent piconets = Child or Neighbor
11. 11 11/24/2008
Piconet hierarchy
• Child piconets
o Offload some of the computational and memory
requirements from the parent
o Extend reach
o Operating on different carrier frequencies
o 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
12. 12 11/24/2008
Piconet operation
• Top level overview
o Starting a piconet
o Creating a child/neighbor piconet
o Handing over control
o Association and Disassociation of DEVs
o Security
o Ending a piconet
14. 14 11/24/2008
Starting a piconet
• Scan all frequencies
• If unused channel is found
o Wait for t = CAP
o Transmit beacon
• If no unused channel is found
o Designated PNC may start a dependent piconet
15. 15 11/24/2008
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
17. 17 11/24/2008
• PNC Shutdown Info Element sent
Ending a piconet
PNC Shutdown PNC Shutdown
PNC ShutdownPNC Shutdown
18. 18 11/24/2008
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
19. 19 11/24/2008
IEEE 802.15.3x
• Older standard (2003) is called IEEE
802.15.3-2003
o Certified by IEEE and WiMedia Alliance
• Specifies only PHY and MAC – no higher
layer services explicitly specified
o 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) techniques
o Utilizes Multiband OFDM (MB-OFDM)
o To be certified by IEEE, MB-OFDM Alliance and
ECMA
20. 20 11/24/2008
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
21. 21 11/24/2008
Ultra Wide Band (UWB)
• Also known as impulse radio, baseband or
Zero-carrier technology
o No upconversion to IF/RF required
• UWB transmits in the form of “extremely
short” pulses
o 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
23. 23 11/24/2008
UWB
• Advantages
o Unlicensed operation
o Simplicity due to baseband transmission
o Information is sent using Pulse Position Modulation
o Very low transmit power
o Interference immunity
o Very high tolerance to multipath
o Data rates in the order of 100 Mbps
o Scales well with semiconductor technology
24. 24 11/24/2008
WirelessHD
• Specification finalized in October 2007
• Wireless High Definition
o HDTV requires 33% higher data rates than SDTV
o Compressed video and audio using MPEG and
H.264/AVC
o Advanced device and audio/video control protocol
o Unlicensed operation
o Data privacy for user generated content
o LOS antenna to ensure P2P
• Operates around the 60 GHz band
o Bandwidth of 7 GHz
• Transmit power of not more than 10 W
• Reach of ~ 10 m
25. 25 11/24/2008
WirelessHD
• 2 modes of operation
o High Rate WiHD
o Low Rate WiHD
• Explicit Feedback Beam Forming
• Implicit Feedback Beam Forming
26. 26 11/24/2008
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
mandatory
o 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
28. 28 11/24/2008
Wireless HDMI
• High Definition Multimedia Interface
o 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
29. 29 11/24/2008
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
Coupling
o “Touch and Get”
