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Tahir Iqbal, Air University 2
• Text Books: – Rappaport, Theodore S., “Wireless Communications Principles and
Practice” 2/e, Prentice Hall PTR– Jochen H. Schiller, “Mobile Communications”, 2nd edition © 2004,
Addison-Wesley
• Reference Books: – Ulysis Black, “Mobile & Wireless", Printice Hall Co.– Bud Bates, "Wireless Network Communication", Mc-Graw Hill.– Asha Melotra, "GSM System Engineering.", Artech house Inc. London.– Demy stified, "3G - Wireless ", Mc-Graw Hill.– Charles Perkins, “Mobile IP”
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Objective of course
• The objective of this course is to familiarize the students about the fundamentals of Wireless and Mobile Communications covering the above mentioned topics.
• The course will also introduce the students with the modern trends in Wireless and Mobile Communications, WAP Applications, wireless Networks standards, ISDN, GSM architecture, services, cellular principles, Cross-layer designing for wireless Network, ad-hoc network, wireless sensor network and security issues in ah-hoc and wireless sensor network.
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• The course will mainly cover the following topics: – Modern Wireless Communication Systems– The Cellular Concepts– Mobile Radio Propagation– Modulation Techniques for mobile radio– Multiple Access techniques for wireless
Communications – Wireless Networking– Wireless Systems and Standards
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Grading and General Course Policies
• Visit class folder regularly for course updates, announcements, and for other course materials. Go to Common=>(Your Class:BETE04…)=>Wireless Communications
• Assignments and/or grade percentages are subject to change. The breakdown is as follows:
Quizzes 10%Project(NS2)/Articles 20%Mid Term 30%Final 40%Total 100%
• No makeup tests will be given• No late assignments will be accepted.• Late phase assignments will not be accepted. • All assignments submitted should be the outcome of individual work only. Group
work is explicitly prohibited (severe penalties for violation).
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Some useful Wireless Links
Stanford Course on Advanced Topics in Wireless Communications (Network Focus).
Wireless and Mobile Networking Course by Y. Altunbasak at Georgia Tech. Advanced Wireless Class by J. Andrews at UT Austin. Mobile and Wireless Networks and Applications Course by Mary Baker at Stanford.
Wireless Information Networks Laboratory Rutgers University. Berkeley Wireless Research Center University of California at Berkeley. Center for Wireless Communications University of California at San Diego. Center for Wireless Information Network Studies Worcester Polytechnic. Bluetooth Homepage. Packet Radio Reading List. Resource and Course Website for William Stallings Book on Wireless Communications and Networks..
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Organization of the Lecture1.1) Introduction to Wireless Communication
1.2) An Overview of Applications and Examples of Wireless Communication
1.3) Historical Evolution and Trends in Wireless Communications
1.4) Terminology and Definitions of Wireless Communication Systems
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Why Mobile Communication?
Question: Why do we need a new technology when we have such a developed public telephone network. The answer is mobility.
This course is about Wireless Communication, with emphasis on Mobile (also known as Cellular) Radio Communication Systems.
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Challenges of mobility
Challenges of using a radio channel: The use of radio channels necessitates methods of sharing them – channel
access. The quality of the path - a more challenging problem than with wires.
Bandwidth: it is possible to add wires but not bandwidth. So it is important to develop technologies that provide for channel reuse.
Privacy and security - a more difficult issue than with wired phone. Others: low energy (battery), hand off, etc.
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Historical Evolution and Trends in Wireless Communication
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Early History of Wireless Communication
Many people in history used light for communication. 1. heliographs, flags (“semaphore”) 2. 150 BC smoke signals (Polybius, Greece) 3. 1794, optical telegraph, Claude Chappe
b. Later on Electromagnetic waves became important: 1. 1831 Faraday demonstrates electromagnetic induction. 2. J. Maxwell (1831- 79): Theory of electromagneticfields, wave
equations (1864) 3. H. Hertz (1857-94): demonstrated the wave character of electrical
transmission through space.
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Historical Background
• Evolution of Voice Oriented Wireless Networks – The origin of wireless communication dates back to the era of
Marconi ---- 1897, when he demonstrated the radio’s communication ability to provide continuous contact with the ships sailing the English channel.
– Mobile telephone service was first offered by AT&T in 1946. This service was mobile, but not cellular. The base station had a coverage of about 100 km.
– Early systems, based on FM, required 120 KHz of spectrum for an information bandwidth of 3 kHz. Large equipment (mounted in cars). Low capacity: 50 users or more cause overloading, 65% blocking probability. Multiple Access method used was FDMA.
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• Next step was the introduction of trunking - relaxing the constraint of using a channel for each user. Frequency-agile radio to search for free channels.
• Cellular concept emerges in early 1970s. Cellular is not a new technology but rather a new organization. Replication of the wide-area network concept. Cellular concept leads to frequency-reuse concept. By late 60's there we,re 70,000 users throughout US.
• Invention of the microprocessor facilitated the implementation of the complex control algorithms required mainly for switching between base stations.
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• Digital control link emerged, regulatory obstacles were cleared and 1 st generation (1 G) systems were deployed in 1983.
• Early 1990s digital voice was developed - 2nd generation (2G) systems. Smaller and longer-life batteries. Miniaturization of the handset
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Tahir Iqbal, Air University 16
The current status of Wireless Communication
• The modern era has seen extremely rapid growth in Wireless Communication, especially in Cellular communication.
• Nowadays, because of the growth of other parallel engineering fields, and the state of the art available technology, Wireless Communication is enjoying the fastest growth period in history.
• It is also the fastest growing field, by any measure, of today’s world.
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• There are about 1billion cellular phone users in the world. • Income of wireless industry surpasses that of wired telephone
industry. • The Internet brought the computer communications industry
from the office to home. • The information exchange industry consists of:
– Fixed telephone – Wireless – Internet
• It is by far the largest industry in the world
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• 1982 Deployment of 1st generation Nordic analog NMT • 1983 Deployment of US Amps • 1988 GSM development • 1988 IS-54 development • 1988 CDMA development • 1991 GSM deployment • 1993 IS-95 development • 1995 PCS band auctions • 1998 3G standardization started
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Personal Communication Systems
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Examples of Mobile Radio Communication Systems
• Paging • Amateur Radio • Citizen Band (CB) Radio • Cordless Phones • Mobile Telephones • Satellite Phones • Radio Communication with aircrafts and ships • Global Positioning System (GPS) • Wireless Networks (both LANs and WANs) • Personal Communication Systems, such as: • Garage door opener
– Remote Controls for various appliances – Localization / Position Finding Systems – Remote Controlled Vehicles and un-manned planes etc
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Tahir Iqbal, Air University 22
Wide Area Paging System
• The paging control center dispatches pages received from the PSTN throughout several cities at the same time
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Satellite linkSatellite link
Wide Area Paging System
Landline linkLandline link
Landline linkLandline link
City 1: Paging terminal
City 1: Paging terminal
City 2: Paging terminal
City 2: Paging terminal
City N: Paging terminal
City N: Paging terminal
Pagingcontrolcenter
Pagingcontrolcenter
PSTNPSTN
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Paging systems are communication systems that send brief messages to a subscriber...
• Numeric messages • Alpha-numeric message • Voice message• News headlines• Stock quotes• Faxes
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Paging Systems Coverage Area
• 2 to 5 km • Within individual buildings • Worldwide coverage
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Wireless Applications • Two classes of applications:
– voice oriented – data oriented
Voice-oriented applications evolved around wireless connections to PSTN.
• Local area voice oriented: low-power, low-mobility, high quality voice:
cordless phone, PCS • Wide area voice oriented: high-power, high mobility, comprehensive coverage, lower quality than local area.
cellular wireless
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Wireless Data Applications
• Data oriented: broadband local and ad hoc, wide area mobile data market.
• Local – WLANs and wireless personal area networks (WPANs)wireless high speed Internet access.
• Wide area Internet access to mobile users.
• Concept of Mobile IP: user carries his lap-top while sitting in his car---internet connectivity via
cellular networks
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Tahir Iqbal, Air University 29
Terminology
• Mobile - historically, any radio terminal that can move during operation. More recently, a terminal attached to a high speed moving platform
• Portable - walking.
• Subscriber- user paying a subscription fee. • Base station - connected to a commercial power
source and a fixed backbone network.
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• Simplex / half-duplex / full-duplex • Simplex - one way communication e.g. paging.
• Half duplex - two way communication, using some radio channel. User can only transmit or receive e.g. "push-to-talk’’ feature.
• Full duplex - use separate channels. Frequency division duplexing FDD – uses single antenna with duplexer.
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Terminology and Definitions• Control Channel:
– Radio channel used for transmission of call setup, call request, call initiation and other control purposes.
• Voice Channel: – Radio channels used for transmission of voice
• Hand-off: – The process of transferring a mobile station from one channel or base station
to the other during the conversation.
• Roamer: – A mobile station which operates in a service area other than that from which
service has been subscribed.
• Page:– A brief message which is broadcast over the entire service area, usually in a
simulcast fashion by many base stations at the same time.
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• Transceiver: – A device capable of transmitting and receiving radio signals
• Frequency Division Duplexing (FDD): – Duplexing means transmitting and receiving simultaneously.
When transmitter and receiver use different frequency channels, it’s called FDD.
• Time Division Duplexing (TDD): – When Transmitter and Receiver use different Time Slots for
duplexing purposes, this is called TDD.
