Title: Wireless Communication Engineering Fall 2004
1Wireless Communication Engineering(Fall 2004)
- Lecture 1
- Professor Mingbo Xiao
- Sept. 23, 2004
2Lets Know Each Other
- My Self-Introduction
- Course Objectives and My Wishes
- Your Self-Introduction (Name, Major, Reasons for
taking this course, etc.) - Suggestions are always welcome and sometimes
required ?
3Recommended Background
- Digital Communications
- Computer Networks
- Probability and Stochastic Processes
4Grading
- Final (Exam/Project/Paper) 34
- Midterm 33
- Homework Quiz 33
- NO late submission or
- any type of cheating
- is allowed in this class.
- Homework is due before the next lecture starts.
5Whats QUIZ?
- QUIZ is also known as POP QUIZ.
- Its a very nice way for the teacher to find out
who is absent. ? - It is usually unannounced -B.
- When you find out its real meaning, you may want
to say it like QUIZzzzzzzzzzz - Still unclear?
6QUIZ 1
- Given two boxes of GO chesses. Put a handful of
the black chesses into the white box, mix them,
and then take a handful of the mixed chesses back
to the first box. - Question Which one is larger, the number of
black chesses in the white box or the number of
white chesses in the black box?
7How about Homework?
- Homework is different from quiz in that you can
answer it off the class. - HW1 Answer the following questions in no less
than 500 English words - What do you expect to learn from this course? Any
plan on how to achieve it? - What are your opinions on the bilingual teaching
for a major course like this one?
8Textbook and References
- Wireless Communication and Networks (by William
Stallings ISBN 0-13-040864-6 Publisher
Prentice Hall, 2002) - Wireless Communication and Networks (by Weihua
Zhuang etc., Chinese edition) - Principles of Wireless Networks A Unified
Approach (by Kaveh Pahlavan etc., Publisher
Science Press, 2003) - Notes and Handouts
9Internet and Web Resources
- Web page for the textbook
- WilliamStallings.com/Wireless1e.html
- Useful web sites, errata sheet, figures, tables,
slides, internet mailing list, etc. - Student Support Site
- WilliamStallings.com/StudentSupport.html
- Newsgroups
- comp.std.wireless
- comp.dcom.
10Tentative Course Outline
- Week 1 Introduction of Wireless Networks
(Evolution, Promises, and Challenges) - Week 2 Wireless Communication Principles
- Week 3 Computer Networking Basics
- Week 4-5 Wireless Channels and Antenna
- Week 6 Multiple Access Techniques
- Week 7 Concepts of Cellular and 1G Systems
- Week 8-10 2G Cellular Systems
11Tentative Course Outline (Contd)
- Week 11-12 3G and Beyond Systems
- Week 13 Wireless LANs
- Week 14 Ad Hoc Networks
- Week 15 Mobile IP
- Week 16-17 Exams and Presentations
12Wireless Is Hot
- Billions of wireless devices are in use
- 4 wireless technologies in 10 communication
technologies with most market potential - Wi-Fi
- UWB
- Software Radio
- Wireless Mesh
- Other six are Nanotech, PON, Soft Switching,
MPLS, FSO, Optical Switching
13Introductions to Wireless Communications
- Communication is an essential need of human
being, e.g., conversation, letter - Wireless used to be the only (limited and
unreliable) way to communicate in ancient times
??????????????????? - Modern wireless communications are based on the
electromagnetic field theory (Maxwells
equations, Marconis invention)
14Introductions to Wireless Communications (Contd)
- Wireless is often prior to its wired counterpart
and has become an important supplement - Marconis Wireless Telegraph ? Wired Telegraph
Telephone ? Cordless, Cellular Telephone, and
Wireless Local Loop - Broadcast TV ? Cable TV ? Satellite TV
- Aloha Network ? Ethernet ? Wireless LAN
15Characteristics of Wireless Comm.
- Convenience and reduced cost
- Service can be deployed faster than fixed service
- No cost of cable plant
- Service is mobile, deployed almost anywhere
- Unreliable channel (attenuation, fading,
shadowing, interference) - Complicated design and management
- Device limitations (power supply, LCD)
- Limited bandwidth and expensive service
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17EM Spectrum for Telecom
- Most spectra licensed 3G license is very
expensive FCC is a mighty sector - Infrared, ISM band, and amateur radio band are
license-free - HW2 Find out what spectrum is used for GSM,
IS-95, 802.11b WLAN. What data rates are
available in each system? What transmission
characteristics makes these spectrum bands
suitable for wireless communications?
18Evolution of Wireless Systems
- Guglielmo Marconi invented the wireless telegraph
in 1896 - Communication by encoding alphanumeric characters
in analog signal - Sent telegraphic signals across the Atlantic
Ocean - First public mobile (car-based) telephone system
(MTS) introduced in 1946 - Analog frequency modulation
- High power BS tower to cover 50 miles radius
- Inefficient (120K spectrum for a voice connection)
19Evolution of Wireless Sys. (Contd)
- Improved mobile telephone system (IMTS) developed
in 1960 - Full duplex services and direct-dialing
- 23 FM channels with BW reduced to 25-30 KHz
- Cellular concept
- Exploits the attenuation of radio signal with
distance to achieve frequency reuse. - originally proposed by D. H. Ring in 1947
- Bell Labs began work on cellular telephone system
in the late 1960s.
20Evolution of Wireless Sys. (1G)
- Handoff was not solved until the development of
microprocessor, efficient remote-controlled RF
synthesizer, and switching center. - 1G Cellular System
- Designed in 1970s, deployed in early 1980s
- Analog, 42 control channels, 790 voice channels
- Handoff performed at BS based on received power
- AMPS in US TACS in part of Europe NTT in Japan
C450 in West German, and NMT in some countries. - Became highly popular AMPS still popular in US!
21Evolution of Wireless Sys. (2G)
- 2G Systems
- Digital cellular telephony
- Modest data support, incompatible
- GSM a common TDMA technology for Europe claim
about 3/4 of subscribers worldwide. - IS-54 and IS-136 TDMA technology in US
compatible with AMPS - IS-95 CDMA standardized in 1993 South Korea
and Hong Kong deployed it in 1995 US in 1996.
22Evolution of Wireless Sys. (2.5G)
- 2G telephony is highly successful
- Enhancement to 2G on data service
- GSM HSCSD and GPRS
- IS-95 IS-95b
- IS-136 D-AMPS and CDPD
- The improved data rate is still too low to
support multimedia traffic - ITU initiated 3G standardization effort in 1992,
and the outcome is IMT-2000.
23Evolution of Wireless Sys. (3G)
- IMT-2000 comprises several 3G standards
- EDGE, data rate up to 473Kbps, backward
compatible with GSM/IS-136 - cdma2000 (Qualcomm), data rate up to 2Mbps,
backward compatible with IS-95 - WCDMA (Europe), introduces a new 5MHz channel
structure data rate up to 2Mbps - TD-SCDMA (China), CDMA in TDD fashion
24Evolution of Wireless Sys. (4G)
- Problems of 3G systems
- Immature 3G license auction increases the
financial burden - What are the killer applications of 3G?
- No unified standard (political factors dominate)
- 4G systems
- Research initiated, but still not well-defined
- Data-oriented, seamless integrated with wireline
- Indoor data rate up to 100 Mbps, outdoor data
rate up to 20Mbps.
25Evolution of Mobile Radio Communications
26Paradigm From 1G to Beyond 3G
27Mobility and Information Speed of Evolving
Mobile Communication Systems
28Trends in Wireless Commun.
- Personal Communications (Goal of mobile
communications) - All IP based (IPv6) (Packet switched)
- Flexible platform of complementary access
systems( Combination of different wireless
access systems, Hot spot services will be
introduced by high-speed wireless access
(gt100mbps)) - Higher system capacity (Users/Service, 5-10
times higher than 3G) - Higher Transmission Data rate
- Higher frequency efficiency
- More advanced multimedia applications
- Improved QoS
- Realize high levels of security and
authentication - Global coverage
- Global roaming
29All IP Based
30All IP based
Mobile InternetApplication Servers
Broadband Accesses
Network Domain
Mobile Internet Application Platforms
Mobility, Connection Control Servers
Broadband Gateway
Service Domain
OWLAN
IP Multi Radio
IP/ATM/MPLS Backbone
Mobility Gateway
Intelligent Edge
Media Gateway
31Combination of different wireless access systems
IEEE.802.11 WLAN
PAN Bluetooth
PDMA
WPAN WLAN WWAN
32Network of 3G beyond
33Transmission Data Rate
- Highest data rate(3G)
- at least 144 Kb/s in a vehicular environment,
- 384 Kb/s in a pedestrian environment,
- 2048 Kb/s in an indoor office environment.
- Highest data rate (4G)
- 2Mbps in a vehicular environment,, 20Mbps in a
pedestrian environment - Wide Area, high velocity100Mbps
- Indoor, lower velocity1Gbps
- Evolution of transmission data rate
34System Capacity and spectrum efficiency
Capacity 5-10 times higher than 3G Frequency
efficiency Multi-cell gt 2bits/Hz
Single-cell 510 bits/Hz
35Drivers of 3G Beyond
- 3G evolution but difficult
- to extend to higher data rate with CDMA only
technology - to provide various services with different QoS
- to have enough frequency resource to accommodate
more subscribers - Drawback
- Low system capacity
- Low spectrum efficiency
36Drivers of 3G Beyond
and Beyond
3G
Evolution from 2G systems
2G
37Service Forecast for Asia Region
38Multimedia Services
- Internet access
- Shopping/banking(e-commerce)
- Video conferencing
- Video on demand
- Telemedicine
- Distance learning
39Ad Hoc Networks
- Self-configuring mobile networks with no
infrastructure - Rapid deployment and reconfiguration
- Robust to node failure
- A necessity in the battlefields of the future?
- Despite much research activity, there remain many
significant technical challenges
40Challenges
- Unreliable Channels (Cross Layer Design)
- Scarce Spectrum and Resource Management
- Stringent Power Budget
- Security
- Location and Routing
- Interfacing with Wired Networks
- Health Concern
- Diversified Standards and Political Struggle
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42Whats Your Wireless Dream?
- Whoever, Whenever, Wherever, Whomever, Whatever
personal communication? - Shrinking the world into earth village?
- Outdoor classroom on lawn under trees?
- Call for help in icy storm?
- Browsing web on cozy seashore?