Wireless technologies of IEEE 802.15.x - Infrared - Bluetooth - UWB (ultra wide band) - Wireless USB - ZigBee

1. IEEE 802 Organization
LAN/MAN Standards Committee (Wireless Areas)
WLAN™ WPAN™ WMAN™ MBWA
IEEE 802.11 IEEE 802.15 IEEE 802.16 IEEE 802.20
802.15.1
“Bluetooth”
802.15.2
Coexistence
802.15.3 Task Group 3a
“High Data Rate” MAC &
Alt PHY (UWB)
2.4 GHz PHY
802.15.4 Study Group 4a
“Zigbee” 2.4 GHz (UWB?)

3. What is Bluetooth?
• Open Standard for Short Range Wireless Connectivity
• Designed for Transmitting Data and Audio Wirelessly
• Uses Radio Frequency (RF) Technology in the Unlicensed 2.4Ghz ISM
Frequency Band.
• Initial Target Applications include PC & PDA Peripherals, Wireless Audio
& Data, Data Synchronization, In-Vehicle (Telematics)
• Future Applications include Wireless Access Points, Healthcare,
Industrial Applications, Cordless Telephony, Smart Appliances,
Entertainment – Wireless Gaming.
• Provides for Ad Hoc device Connection and Service Discovery
• Promises Lower Power Consumption and Lower Cost per Node Than
Competing Wireless Technologies

4. Why Bluetooth?
• More Robust than Infrared (IrDA).
– RF based, not limited to line-of-sight.
– Supports 10 meter range (class 2), versus 1 meter.
• Power Consumption
– Bluetooth provides several classes of operation that
provide significant power advantages over other
wireless alternatives such as 802.11
• Projected to be Less Costly Than 802.11 & HomeRF.
– 802.11 & HRF estimate is > $25 per node, Bluetooth
target is < $ 5 when embedded in volume.
– Bluetooth costs will start declining sharply 1st half
2003.

5. Why Not Bluetooth?
• Range
– 802.11 WLAN & Home RF provide greater connection
distance
• Data Rate
– Bluetooth today provides 1Mbps raw data rate,
lower than competing technologies, 802.11b
(11Mbps), 802.11a (54Mbps)
• Hyped expectations have damaged its credibility
• Available 2 years latter than expected
• Interoperability problems with early products
• Interference from other products in the ISM band
• Future Technologies Promise Lower Power, Lower Latency
– wireless USB

6. Summary
• Bluetooth got off to a slow start but Momentum is Building
• Key Revenue Generators Today are Audio related (Headsets &
In-Vehicle Applications) and Data Related
• Currently 819 Qualified Products listed on the SIG web site,
more added daily
• For Further BT V1.1 Specification and Profile details, go to
www.bluetooth.com

7. Ultra Wide Band

8. Range and Data Rate

9. Introduction
• What is UWB?
– A series of very short baseband pulses with time
duration in nano-seconds that exist on ALL
frequencies simultaneously, like a blast of
electrical Noise.
• Synonyms:
– Non-sinusoidal Communication Technology
– Impulse Radio
– Baseband Pulse Technology

10. Large Relative (and Absolute) Bandwidth
Narrowband (30kHz)
Part 15 Limit
Wideband CDMA (5 MHz) ( -41.3dBm/Hz )
UWB (Several GHz)
Frequency
• UWB is a form of extremely wide spread spectrum where
RF energy is spread over gigahertz of spectrum
– Wider than any narrowband system by orders of magnitude
– Power seen by a narrowband system is a fraction of the total
– UWB signals can be designed to look like imperceptible
random noise to conventional radios

11. Why is UWB attractive?
– Capacity: a channel is linearly proportional to its
bandwidth. UWB can go up to 2 Giga-Hz in bandwidth.
• Spread spectrum: transmission in which the data sequence
occupies a bandwidth in excess of the minimum bandwidth
necessary to send it. It uses only several frequencies, one at a
time.
• Successor to spread spectrum: UWB uses every frequency there is,
use them all at same time.
– Simplicity: it’s essentially a base-band system (Carrier
free), for which the analog front-end complexity is far less
than that for a traditional sinusoidal radio. (See Figures at
next page.)

12. Why is UWB attractive?
• 7.5 Ghz of “free spectrum” in the U.S.
– FCC recently legalized UWB for commercial use
– Spectrum allocation overlays existing users, but its allowed
power level is very low to minimize interference
• Very high data rates possible
– 500 Mbps can be achieved at distances of 10 feet under current
regulations
• “Moore’s Law Radio”
– Data rate scales with the shorter pulse widths made possible
with ever faster CMOS circuits
• Simple CMOS transmitters at very low power
– Suitable for battery-operated devices
– Low power is CMOS friendly

13. Pros
• High data capacity.
– Multiple Access provided by time hopping scheme. Can support close to 30,000
users at 19.2kbps with BER of 10-3 or a 6 users system with a peak speed of
50mbps.
• Low power.
– Transmitting at microwatts (one tenth thousandth power of cell phone) results in very low
harmful interference to other radio systems. Usually below the noise floor and
undetectable.
– Longer battery life for mobile devices.
• Resilient to distortions and fading (Great for indoor usage).
– Spread spectrum property overcomes frequency selective fading.
– High information redundancy and frequency diversity provides protection
against multi-path distortion.
• Simplicity translate to lower hardware cost.
– No carrier frequency translate analog front-end has simpler implementation
than traditional sinusoidal radio.
• Security
– UWB is inherently secure: Only a receiver that knows the schedule of the
transmitter can assemble the apparently random pulses into a coherent
message.

14. Cons
• Interference with GPS.
– Global positioning satellite currently have more than 10 million users and it’s
primarily applications are used for the safety of public. (I.e. aircraft flight and
approach guidance.) UWB presents a problem to GPS because their frequency
overlaps, and GPS signal is particular sensitive to interference (It as SNR level
around –164 dBW.)
• Limited on range
– Output power is limited in order to keep down the noise floor due to its
overlapping frequency bandwidth with other radio systems.
• One kilometer with high gain antenna.
• Ten to twenty meter with regular antenna.
• Affects on economy and current businesses.
– Speculations on UWB making current billion dollar FCC licensed frequencies
worthless.
– Increased competition for local cable or phone company. Making their existent
investments on cable and equipments obsolete.
• Side Note.
– FCC adopted a First Report and Order that permits the marketing and operation of
certain types of new products incorporating UWB technology, Feb 14,2002.
– Biggest loser: Increase the noise floor level for radio astronomer.

15. Possible Research Topics for
UWB
• UWB as WPAN (IEEE 802.15.3a)
currently, debating with PHY layer and MAC layer
- optimal MAC vs. 802.15.3 MAC vs. 802.11a MAC
- QOS scheduling algorithm for multimedia stream
- Interoperability with 802.11, Bluetooth, wired LAN, sensor network(?)
- security policy
• UWB as Localization device (in sensor network or other mobile node)
- optimal localization protocol in ad hoc network
(task dispatching between UWB and RF unit)
- security issue
• UWB as alternate RF component (in sensor network or other mobile
node)
- optimal MAC
- routing algorithm
- QOS scheduling

17. Wireless USB Vision

18. Physical Design
• Features of wUWB
– Speed/Range
• Scaleable speeds up over 1 Gbps
• Currently 480 Mbps at 3 m; 110 Mbps at 10 m
– Frequency: 3.1 GHz to 10.6 GHz
• Divided into 14 bands; 5 groups
– Each band is 528 MHz wide
– OFDM symbols are interleaved across all bands
– Provides protection against multi-path / interference

19. Physical Design
• Features of wUWB (cont.)
– Frequency: 3.1 GHz to 10.6 GHz (cont.)
• Band Groups 1 & 2: Longer range apps
• Bands Groups 3 & 4: Shorter range apps
• Bands can be turned off to accommodate for conflicts or for
regulations

20. Physical Design
Features of wUWB (cont.)
- Power
• Power is limited due
to usage of wide spectrum
• Low power for mobile
devices and minimum
interference
• Max output to
-41.3 dBm/MHz

21. Wireless USB Connection
Design
• Host/Slave Connection
– Similar to wired USB (127 devices; host is PC)
– Each host forms a cluster
– Clusters can coexist with minimum interference
• Power Management
– Sleep/Listen/Wake
used to conserve
power
– Tx/Rx power
management

22. Issues/Problems
• Interference Issues
– Potential conflict to devices on same frequencies
– “Detect and Avoid”
• Wisair’s solution to detect other frequencies
• Switches to frequencies not being used
– Conflict issues are more of a concern for wireless USB devices being
overpowered
• Competing Standards
– Cable-Free USB (Freescale)
– USB-Implementers Forum (Intel, HP, Microsoft)

23. Concluding Thoughts
• Appears well designed; good support
• Slow start of products
– Will it really catch on?
– More products need to be developed
• Promises a lot; will it deliver?
• Security is very important

24. Zig Bee

25. Market Application Landscape
Graphics Hi-Fi Digital
Text Internet audio Streaming video Multi-channel
video video
WAN
Long Range
GSM/CDMA GPRS/3G LMDS
Wi-Fi Wi-Fi5
802.11b LAN
802.11a/HL2
Short Range
ZigBee Bluetooth 2
802.15.4 WiMedia
Bluetooth 1 802.15.3
802.15.1 PAN
Low Data Rate High Data Rate

26. Why ZigBee?
• Standard in a fragmented market
– Many proprietary solutions, interoperability issues
• Low Power consumption
– Users expect battery to last months to years!
• Low Cost
• High density of nodes per network
• Simple protocol, global implementation

27. ZigBee vs Bluetooth
Competition or Complementary?

28. But ZigBee is
Bluetooth is Best Better
For : IF :
• Ad-hoc networks between • The Network is static
capable devices • Lots of devices
• Handsfree audio • Infrequently used
• Screen graphics, pictures… • Small Data Packets
• File transfer

29. Timing Considerations
ZigBee:
• New slave enumeration = 30ms typically
• Sleeping slave changing to active = 15ms typically
• Active slave channel access time = 15ms typically
Bluetooth:
• New slave enumeration = >3s
• Sleeping slave changing to active = 3s typically
• Active slave channel access time = 2ms typically
ZigBee protocol is optimized for timing critical applications