Wireless Communication ?

littleparsimoniousΚινητά – Ασύρματες Τεχνολογίες

21 Νοε 2013 (πριν από 4 χρόνια και 1 μήνα)

97 εμφανίσεις

1
工程與生活
生活在無線通訊的時代
電子系暨電信所
洪萬鑄
2007 SPRING
NCUE EE&CM
2
Wireless Communication ?
2007 SPRING
NCUE EE&CM
3
Transportation
Global
Networking:
Ready for
Future Roles?
Critical
Infrastructure
Telecommunications
Banking & Finance
2007 SPRING
NCUE EE&CM
4
WirelessApplications
Remote Control
Remote Patient Monitoring
Auto -Key Fobs,
Tire Pressure Monitor
Wireless Security
Wireless HeadphonesRemote Toys
2
2007 SPRING
NCUE EE&CM
5
Digital Living
2010
Tomorrow’s users will be surrounded by pervasive devices,
embedded sensors and systems…all connected to the Internet.
User
Home Computer
PDA
Telephone
Entertainment Systems
Car
Surveillance and Security
(at home, work, or in public)
Building Automation
Banking
and
Commerce
Photography
Home Appliances
Games
Inventory/Sales
tracking
Health/Medical
Communications
User
User
User
Thanks to Peter A. Freeman at NSF
2007 SPRING
NCUE EE&CM
6
The Pioneers of Mobile Communication
2007 SPRING
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7
The Titanic
2007 SPRING
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8
First Mobile Radio Telephone
1924
3
2007 SPRING
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9
Claude Elwood Shannon
Claude Elwood Shannon
( 1916 -2001 )
Father of Information Theory
Electrical engineer, mathematician,
and native son of Gaylord. His creation
of information theory,
the mathematical theory of
communication, in the 1940s and
1950s inspired the revolutionary
advances in digital communications
and information storage that
have shaped the modern world.
This statue was donated by the
Information Theory Society of the
Institute of Electrical and Electronics
Engineers, whose members follow
gratefully in his footsteps.
Dedicated October 6, 2000
Eugene Daub, Sculptor
2007 SPRING
NCUE EE&CM
10
Wireless
Wired
Each cable is a different channelOne media (cable) shared by all
Signal attenuation is low
High signal attenuation
No interference
High interference noise; co-channel interference;
adjacent channel interference
Wired Vs. Wireless Communication
2007 SPRING
NCUE EE&CM
11
Transparent Information Access
Policy-based
Location-based
Activity-based
Speech-to-Text
Speech-to-Voice Attached-Email
Call-to-Pager/Email Notification
Email-to-Speech
All compositions
of the above!
Universal In-box
2007 SPRING
NCUE EE&CM
12
Mobile and Wireless Services –Always
Best Connected
UMTS
2 Mbit/s
UMTS, GSM
384 kbit/s
LAN
100 Mbit/s,
WLAN
54 Mbit/s
UMTS, GSM
115 kbit/s
GSM 115 kbit/s,
WLAN 11 Mbit/s
GSM/GPRS 53 kbit/s
Bluetooth 500 kbit/s
GSM/EDGE 384 kbit/s,
DSL/WLAN 3 Mbit/s
DSL/ WLAN
3 Mbit/s
4
2007 SPRING
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13
Effects of device portability
Power consumption

limited computing power, low quality displays, small
disks due to limited battery capacity

CPU: power consumption ~ CV
2f

C: internal capacity, reduced by integration

V: supply voltage, can be reduced to a certain limit

f: clock frequency, can be reduced temporally
Loss of data

higher probability, has to be included in advance into
the design (e.g., defects, theft)
Limited user interfaces

compromise between size of fingers and portability

integration of character/voice recognition, abstract
symbols
Limited memory

limited value of mass memories with moving parts

flash-memory or ? as alternative
Wireless systems:
overview of the development
cellular phones
satelliteswireless
LAN
cordless
phones
1992:
GSM
1994:
DCS 1800
2001:
IMT-2000
1987
CT1+
1982:
Inmarsat-A
1992:
Inmarsat-B
Inmarsat-M
1998:
Iridium
1989:
CT 2
1991:
DECT
199x:
proprietary
1997:
IEEE 802.11
1999:
802.11b, Bluetooth
1988:
Inmarsat-C
analogue
digital
1991:
D-AMPS
1991:
CDMA
1981:
NMT 450
1986:
NMT 900
1980
CT0
1984
CT1
1983:
AMPS
1993:
PDC
4G –fourth generation: when and how?
2000:
GPRS
2000:
IEEE 802.11a
200?:
Fourth
Generation
(Internet
based)
2007 SPRING
NCUE EE&CM
15
Wireless Technologies -Roadmap

Tremendous transformation in the devices

Manifold increase in bandwidth delivery

Service capabilities & Mobility

Wireless has already manifested itself as the choice of technology for
backhaul, last mile, LAN & Personal applications
Microwave
Satellite
VSAT
GSM -2G
CDMA –1x RTT
LMDS, MMDS
WiFi–802.11b
Bluetooth
GPRS, EDGE, 3G
CDMA –EV DO
WiFi–802.11a/g
WiMAX–Fixed
RFID
DVB-T, S
UMTS, WCDMA
HSPA, MIMO
4G
Mobile WiMAX
DVB-S / T/ H
NFC
Cognitive Radios
Past
Present
Future
2007 SPRING
NCUE EE&CM
16
Evolution of Wireless Communication
Wi-Fi,WiMax, 3G, 2G
Pockettop:
Mobile phone
Laptop:Mobile computer
Necktop:Brains
Servers,
Databases
2G, 3G,Wi-Fi,WiMax
Informal&Formal networks
Bluetooth
5
2007 SPRING
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17
Wireless

Access

Technologies

Roadmap
2007 SPRING
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18
Wireless: The Big Picture…
2007 SPRING
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19
Wireless: Understanding the Big Picture…
Wireless (vswired)…
communication medium
Cellular (vsmeshed vsMANETs)…
architectures for coverage,
capacity, QoS, mobility, auto-configuration, infrastructure support
Mobile (vsfixed vsportable)…
implications for devices:
phone vsPSP vsPDA vslaptop vsultramobile
WAN (vsWLAN vsWMAN)…
network scope, coverage,
mobility
Market segments:
Home networks, SOHO, SME, enterprise,
Hotspots, WISPs, cellular …
Technologies/Standards/Marketing Alliances:
802.11,
UWB, Bluetooth, Zigbee, 3G, GSM, CDMA, OFDM, MIMO, Wimax…
2007 SPRING
NCUE EE&CM
20
Mobile
Computing/Entertainment/Commns
Samsung Cameraphone
w/ camcorder
iPoD: impact of disk size/cost
Blackberry: phone + PDA
SONY PSP: mobile gaming
•Computing: smaller, faster
•Disks: larger size, small form
•Communications: wireless
voice, data
•Multimedia integration: voice,
data, video, games
6
2007 SPRING
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21
Modern Wireless Systems
2007 SPRING
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22
IEEE Wireless Standards
IEEE 802.15.3
UWB, Bluetooth
Wi-Media,
BTSIG, MBOA
WAN
MAN
LAN
PAN
ETSI
HiperPAN
IEEE 802.11
Wi-Fi Alliance
ETSI-BRAN
HiperLAN2
IEEE 802.16d
WiMAX
ETSI HiperMAN &
HIPERACCESS
IEEE 802.20
IEEE 802.16e
3GPP (GPRS/UMTS)
3GPP2 (1X--/CDMA2000)
GSMA, OMA
Sensors
IEEE 802.15.4
(Zigbee Alliance)
RFID
(AutoIDCenter)
IEEE 802.21,
IEEE 802.18 802.19
RAN
IEEE 802.22
2007 SPRING
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23
Satellite
Links
SW
Radio
MW
Radio
FM
Radio
Mobile
Telephony,
WLL
WLANs
Blueooth
IR
1,000 Km100 Km10 Km1 Km100 m10 m1 m
Wireless Systems : Range Comparsion
2007 SPRING
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24
Wide Area
Wide Area
Network
Network
Metropolitan
Metropolitan
Area Network
Area Network
Local Area
Local Area
Network
Network
Personal Area
Personal Area
Network
Network
Fixed
Fixed
WIMAX
WIMAX
&
&
2G / 3G
2G / 3G
Mobile
Mobile
WIMAX
WIMAX
&
&
3G
3G
Evol
Evol
Wi
Wi
-
-
Fi
Fi
WiMedia
WiMedia
&
&
BT
BT
Source: WiMAXForum
Broadband Wireless Technologies
7
2007 SPRING
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25
ν
Propagation characteristics are different in each frequency band
UV
1 MHz
1 kHz
1 GHz
1 THz
1 PHz
1 EHz
infrared
visible
X rays
Gamma rays
A
M

r
a
d
i
o
S
/
W

r
a
d
i
o
F
M

r
a
d
i
o
T
V
T
V
c
e
l
l
u
l
a
r
LF
HF
VHF
UHF
SHF
EHF
MF
ν
λ
30kHz300kHz
3MHz
30MHz
300MHz
30GHz300GHz
10km
1km
100m
10m
1m
10cm
1cm
100mm
3GHz
902 –928 MHz
2.4 –2.4835 GHz
5.725 –5.785 GHz
ISM band
EM Spectrum
2007 SPRING
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26
902 MHz
928 MHz
26 MHz
83.5 MHz
125 MHz
2.4 GHz
2.4835 GHz
5.725 GHz
5.850 GHz
cordless phones
baby monitors
WaveLan
802.11b
Bluetooth
Microwave oven
802.11a
λ
33cm
12cm
5cm
ISM Radio Spectrum (In Use)
2007 SPRING
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27
Spectrum Regulation
Spectral Allocation in US controlled by FCC
(commercial) or OSM (defense)
FCC auctions spectral blocks for set applications.
Some spectrum set aside for universal use
Worldwide spectrum controlled by ITU-R
Regulation can stunt innovation, cause economic
disasters, and delay system rollout
ITU-R: International Telecommunication Union-Radio Communication Section
FCC: Federal Communications Commission
OSM: Office of Surface Mining
2007 SPRING
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28
Tx
Rx
How does signal propagate ?
How much attenuation take place ?
How does signal look like at the receiver ?
Understanding Wireless Communication
8
2007 SPRING
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29
a wave
can
be absorbed
reflect
reflect
penetrate
penetrate
bend
Propagation in the “Real World”
2007 SPRING
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hallways
windows
trees
vehicles
rain
hills
girders
walls
The Cluttered World of Radio Waves
2007 SPRING
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31
First Generation (1G)
Advanced Mobile Phone Service (AMPS)
US trials 1978; deployed in Japan (’79) & US (’83)
800 MHz band —two 20 MHz bands
TIA-553
Still widely used in US and many parts of the world
Nordic Mobile Telephony (NMT)
Sweden, Norway, Demark & Finland
Launched 1981; now largely retired
450 MHz; later at 900 MHz (NMT900)
Total Access Communications System (TACS)
British design; similar to AMPS; deployed 1985
Some TACS-900 systems still in use in Europe
2007 SPRING
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32
Defining the Problem -2G
2G Digital Phone
Digital systems
Leverage technology to increase capacity
Speech compression; digital signal
processing
Utilize/extend “Intelligent Network”
concepts
Improve fraud prevention
Add new services
There are a wide diversity of 2G systems
IS-54/ IS-136 North American TDMA; PDC
(Japan)
iDEN
DECT and PHS
IS-95 CDMA (cdmaOne)
GSM
9
2007 SPRING
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GSM
2G Digital Phone
«GroupeSpecial Mobile», later
changed to
«Global System for Mobile»
Joint European effort beginning in 1982
Focus on seamless roaming across Europe
Services launched 1991
Time division multiple access (8 users per
200KHz)
900 MHz band; later extended to 1800MHz
Added 1900 MHz (US PCS bands)
GSM is dominant world standard today
Well defined interfaces; many competitors
Network effect (Metcalfe’s law) took hold in
late 1990sTri-band GSM phone can roam the world
today
2007 SPRING
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The Cellular Telephone Network
2007 SPRING
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Cellular Mobile Telephony
2007 SPRING
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Standards
Interacting systems require standardization
Companies want their systems adopted as standard
Alternatively try for de-facto standards
Standards determined by TIA/CTIA in US
IEEE standards often adopted
Worldwide standards determined by ITU-T
In Europe, ETSI is equivalent of IEEE
Standards process fraught with
inefficiencies and conflicts of interest
ETSI: European Telecommunications Standards Institute
TIA: Telecommunications Industry Association
CTIA: Cellular Telecommunication and Internet Association
10
2007 SPRING
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3G Services
Who is first? –the customer; who is second? -No one
2MHzvideotelemedicine
conferencingVideo onMobile
demandTV
electronic
Internetradionewspaper
Bandwidthpaging
audio
conferencingmessagingMobile
radio
Fax
voice
1KHz
bi-directionalunidirectionalBroadcast/
multicast
2007 SPRING
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Evolution of Cellular Systems
3G systems.
Digital transmission,
Circuit switched voice and data (low speed)
Packet switched data services (high speed ~ 2Mbps,
with QoS).
Integrated Core Network Infrastructure between voice
and data paths.
2007 SPRING
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Key Mobility Services
Multimedia Messaging Services (MMS)
Text, sounds, images, and video
Transition from Short Message Service (SMS)
Open Internet standards for messaging
Web Applications
Information portals
Wireless Markup Language (WML) with signals
using Wireless Application Protocol (WAP)
Location Communications Services
Location Awareness Based
Personalization of information presentation format
Service capability negotiations (MExEenvironment)
2007 SPRING
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Biggest Threat to Today’s 3G —
Wireless LANs
Faster than 3G
11 or 56 Mbps vs. <2 Mbps for 3G when
stationary
Data experience matches the Internet
With the added convenience of mobile
Same user interface (doesn’t rely on small
screens)
Same programs, files, applications, Websites.
Low cost, low barriers to entry
Organizations can build own networks
Like the Internet, will grow virally
Opportunity for entrepreneurs!
Opportunity for wireless operators?
11
2007 SPRING
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Pre-3G Devices
3G+ Devices
Make and Receive Voice Calls
Capture and Transmit
video and still pictures
Text-based Messaging
Listen to Music Files
Download and Play Games
Personalize with Content
Access Office Systems
Browse the Web
GPS
Watch Television
Stream Radio
Advanced
Gaming
Applications on Mobile Broadband
Networks
2007 SPRING
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Source: QUALCOMM
Globally, more than 200 Mobile Broadband
Devices have been Introduced
2007 SPRING
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Beyond 3G (B3G)
By 2010, 66% of the revenues will come from data services
2007 SPRING
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Outside
Campus
Fixed
Walk
Vehicle
Within
Campus
Fixed/
Desktop
Walk
Mobility
C
D
M
A
2
0
0
0

1
X

E
V
-
D
O
&


W
-
C
D
M
A

HiperLAN2
802.11a, g
LAN
802.11b
Wireless Local Area Network
(WLAN)
Public or Private Site or
Campus
Enterprise / premises
application voice & data
network extension
Nomadic
Non-licensed spectrum
Wireless Local Area Network
(WLAN)
Public or Private Site or
Campus
Enterprise / premises
application voice & data
network extension
Nomadic
Non-licensed spectrum
>3G
Mbps
110
100
0.1
CDMA2000 1X
GSM/GPRS
DECT
Bluetooth
Wireless Wide Area Network (WWAN)
Metro/Geographical area
“Always On”Services
Ubiquitous public connectivity
with private virtual networks
Wireless Wide Area Network (WWAN)
Metro/Geographical area
“Always On”Services
Ubiquitous public connectivity
with private virtual networks
Beyond 3G (B3G)
12
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Mobile-IP Operation
Traffic is sent as usual to the home subnet
The home agent intercepts (Proxy ARP) the traffic while
the mobile node is registered as away
Traffic is tunneled to its current location
Traffic from the mobile node can go directly to the
correspondent host
Mobile
Node
Home
Agent
Foreign
Agent
2007 SPRING
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Horses for
courses?
Or
Vs
?
How to compare:
2007 SPRING
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How far it goes depends where your
terminal is
3 Sector base station at 25m to:
Consider a hypothetical broadband (1Mb/s) wireless network

Gain Height Building
loss
Range Relative
site
count
Rooftop – LOS

10 dBi 8 m 0 dB > 30km
Rooftop NLOS

10 dBi 8 m 0 dB 6.2 km 1
Terminal /
Gateway in
upstairs
window
3 dBi 5 m 0 dB 1.8 km 12
Outdoor PCcard

0 dBi 1.5 m 0 dB 780 m 60
Indoor PCcard -
Suburban
0 dBi 1.5 m 10 dB 410 m 230
Indoor PCcard -
Urban
0 dBi 1.5 m 20 dB 210 m 800

All figures except LOS based on COST231-Hata model with 10dB shadow margin and no cable losses. System operates at
2GHz with 1Mb/s from 24dBm EIRP terminal TX, 3dB Eb/No, 5dB NF RX. BS antenna = 18dBi
2007 SPRING
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How far does it goes depends on data
rate
3 Sector base station at 25m to outdoor PC card
100kb/s1.49km
1Mb/s0.78km
10Mb/s 0.41km
100Mb/s 0.21km
Data Rate
Range
Site density
1
3.6
15
50
13
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How far it goes depends on frequency
Range
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How far does it goes depends on technology
Range
UMTS TDD: 64kbps UL / 500kbps
3GPP R99 64kbps UL / 128kbps DL
Proprietary technology (1)
75kbps UL / 600 kbps DL
1.41 km
Proprietary technology (2)
64 kbps UL / 1400 kbps DL
1.56 km
Downlink data rate
1.47 km
Comparison
using 64kbps
uplink as
reference,
what does a
single
user
obtain on the
downlink?
3GPP HSDPA 64kbps UL / 700 kbps DL
1.63 km
1.62 km
2007 SPRING
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What is WiMAX?
Worldwide Interoperability for Microwave Access
(WiMAX) is the common name associated to the
IEEE 802.16a/REVd/e standards.
These standards are issued by the IEEE 802.16
subgroup that originally covered the Wireless
Local Loop technologies with radio spectrum
from 10 to 66 GHz.
WiMAX bridges the last mile wirelessly with
bandwithes that have been unknown until now.
WiMAX is very similar to Wi-Fi but provides Hot
Zones that are a few kilometers wide.
BWA = Broad + Wireless
WiMAX = Broad + Wireless + Interoperability
2007 SPRING
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The Role of WiMAX
WiMAX802.16-2004 addresses primarily the
stationary & nomadic market, whereas 802.16e
goes mobile.
WiMAXbrings broadband into regions where no
DSL or cable is available.
Urban areas: WiMAXas an alternative to DSL and
cable access and for nomadic and portable access.
WiMAX-Certified products guarantee
interoperability thus lower investment costs for the
provider.
Success may / will be Thousands of WiMAX
Networks and Tens of Millions of WiMAXClients
Worldwide.
14
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WiMAXMarket Vision: Broadband
Everywhere
BWA Operator Network
Backbone
INTERNET
BACKBONE
Mobile
Backhaul
3
RESIDENTIAL & SoHoDSL
LEVEL SERVICE
1
802.16d
FRACTIONAL E1 for
SMALL BUSINESS
T1+ LEVEL SERVICE
ENTERPRISE
BACKHAUL for
HOTSPOTS
2
802.16d
H
H
H
H
H
H
H
H
H
WMAN Nomadic Coverage -->
handoff from HOT SPOTS
4
= wide area coverage
outside of Hot Spots
Mobility
5
802.16e
2007 SPRING
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The WiMAXEvolution
Fixed Outdoor Solution Characteristics
Solution Characteristics
•Fixed location
•Installed outside of
subscriber’s house
•Requires truck roll
Applications
Applications
•E1 Level Service for
Enterprises
•Backhaul for Hotspots
•Fractional E1 for SMB
•Limited residential
broadband access (early
adopters, rural,
developing countries)
Mobile
Solution Characteristics
Solution Characteristics
•CPE Native in Mobile PC
•User can roam within the
service area at varying
speeds\
•Always Best Connected
(Simplified Network
Selection)
Applications
Applications
•“Mobile”Broadband
access for consumers
Fixed Indoor & Portable
Solution Characteristics
Solution Characteristics
•Consumer –self install,
auto provisioning
•Portable –can ‘move’
CPE to another location
in service area
Applications
Applications
•“Last Mile”Broadband
access for consumers
•Portable broadband
access
2004
2004
2006
2006
2007
2007
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Operates in 2.5, 3.5, 5.4 or 5.8 GHz frequency
spectrum
Supports LOS and NLOS
Uses OFDM/OFDMA
Adaptive Modulation and Coding (AMC)
TDD and FDD supported
Applies Advanced Radio Techniques
–Diversity Techniques(CDMA/SDMA)
–SmartAntenna Systems (SA)
–Multi-input, Multi-output (MIMO)
WiMAX Technology Overview
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What is WiMAXbringing?
Improved business case opportunity
–Standards based interoperability brings lower
equipment costs
–Increased operator confidence due to reduced
investment risk
Complements LAN & WAN wireless solutions
–Can backhaul other technologies (e.g. Wi-Fihotspots)
–Can overlay mobile networks to offload data traffic
Support for a wide range of deployment
scenarios
−Rural, suburban, urban
−Enterprise, small business, residential
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Interplay among Alternative Technologies
The Game
The hunter has the power to decide who wins
From Dr. C.K. Mao:
Telecom Regulation
(APEC Workshop)
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Bluetooth
Cable replacement RF
technology (low cost)
Short range (10m,
extendable to 100m)
2.4 GHz band (crowded)
1 Data (700 Kbps) and 3
voice channels
Widely supported by
telecommunications, PC,
and consumer
electronics companies
Few applications beyond
cable replacement
2007 SPRING
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Broadband Over Power Lines:
The Third Wire
HomePlug Modem can turn an electrical
outlet into an Internet
connection.
Based on additional analyses, NTIA
recommended several supplements to
the FCC proposed BPL rules to reduce
risk of BPL interference (June 2004)
The FCC adopted rules incorporating
most NTIA recommendations on
October 14, 2004.
Today, many utilities, hotel operators
and others are deploying
experimental and operational BPL
systems.
2007 SPRING
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Adaptiveradios
can adjust themselves to accommodate
anticipated events
Fixed radios
are set by their operators
Cognitive radios
are aware of their environment and
learn how to adapt
Cognitive Radio
16
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BBC News
pacemakers and because of this the
use of mobile telephones is not
permitted in hospital buildings and
within 3 meters of the exterior of any
building. The use of mobile telephones
in hospitals can also disturb other
patients. When you come into hospital
please leave your mobile telephone at
home and please ask your relatives
and friends to remember to turn off
their mobile telephones before
entering hospital buildings. “
University Hospital of
North Staffordshire, UK:
“Mobile telephones
affect the safe operation
of sensitive medical
equipment we use to
treat patients for
example, syringe
pumps, ventilator
equipment or
“…Doctors at a Welsh
hospital are leading the
way in using modern
technology to help speed
up a patient's treatment …”
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Wireless Future :
A Seamless Mobile Lifestyle
HOT SPOTS
Public Networks/
Public Networks/
Internet
Internet
Converged services
Converged services
PUBLIC
TRANSPORT
VEHICLE
WORK
OUTDOORS
RURAL
HOME
Seamless connectivity to
all networks, applications,
& services
Anytime Anywhere
2007 SPRING
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Challenges
Social (e.g. children’s use)
Political (e.g. posting false info)
Policy (e.g. access)
Legal (e.g. copyright)
Technical (e.g. security)
These fundamental issues are closely
These fundamental issues are closely
intertwined and must be addressed if we
intertwined and must be addressed if we
are to realize the opportunities before us.
are to realize the opportunities before us.
17
2007 SPRING
NCUE EE&CM
65
Questions?
Comments?
2007 SPRING
NCUE EE&CM
66
A Favorite 2.4 GHz Antenna