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20-751 ECOMMERCE
TECHNOLOGY
FALL 2003
COPYRIGHT © 2003
MICHAEL I. SHAMOS
Wireless Technologies
20-751 ECOMMERCE
TECHNOLOGY
FALL 2003
COPYRIGHT © 2003
MICHAEL I. SHAMOS
Outline
• Wireless technology overview
• Cellular communications
• Satellite systems
• Wireless LAN
– 802.11, Bluetooth, UWB
• Mobility support
– WAP
• Wireless applications
20-751 ECOMMERCE
TECHNOLOGY
FALL 2003
COPYRIGHT © 2003
MICHAEL I. SHAMOS
Why Wireless?
• Human freedom
– Portability v. Mobility
• Objective: “anything, anytime, anywhere”
• Mobility
– Size, weight, power
– Functionality
– Content
• Infrastructure required
• Cost
– Capital, operational
20-751 ECOMMERCE
TECHNOLOGY
FALL 2003
COPYRIGHT © 2003
MICHAEL I. SHAMOS
Worldwide Mobile Subscribers
SOURCE: CTIA, iGillottResearch, 2001
20-751 ECOMMERCE
TECHNOLOGY
FALL 2003
COPYRIGHT © 2003
MICHAEL I. SHAMOS
Electromagnetic Spectrum
SOURCE: JSC.MIL
SOUND RADIO LIGHT HARMFUL RADIATION
VHF = VERY HIGH FREQUENCY
UHF = ULTRA HIGH FREQUENCY
SHF = SUPER HIGH FREQUENCY
EHF = EXTRA HIGH FREQUENCY
4G CELLULAR
56-100 GHz
3G CELLULAR
1.5-5.2 GHz
1G, 2G CELLULAR
0.4-1.5GHz
UWB
3.1-10.6 GHz