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  1. Introduction – Chapter 1 CENG 5931 - Wireless Communications Textbook: Wireless Communications and Networks2nd Edition by William Stallings

  2. CourseSmart Textbook Option Wireless Communications & Networks by William Stallings • eText ISBN-10: 0-13-186316-9   • eText ISBN-13: 978-0-13-186316-3  CourseSmart is a choice for students looking to save money. As an alternative to purchasing the print textbook, students can subscribe (180 days) to an online version (requires Internet connection) or purchase a download version (no Internet connection required) to the same content online ($64.50) and save as compared to the list price of the print text.

  3. Wireless Comes of Age • Guglielmo Marconi invented the wireless telegraph in 1896 • Communication by encoding alphanumeric characters in analog signal – continuous wave (CW) • Sent telegraphic signals across the Atlantic Ocean • “It is dangerous to put limits on Wireless” - Guglielmo Marconi, 1932 • Communications satellites launched in 1960s • Advances in wireless technology • Radio, television, mobile telephone, communication satellites – initially RF based analog systems in the VHF/UHF spectrum • More recently • Satellite communications, wireless networking, cellular technology – digital RF in the microwave spectrum

  4. Broadband Wireless Technology • Higher data rates obtainable with broadband wireless technology • Graphics, video, audio • Shares same advantages of all wireless services: convenience and reduced cost • Service can be deployed faster than fixed service • No cost of cable plant • Service is mobile, deployed almost anywhere • Ubiquitous Computing (Mark Weiser/Xerox Parc) – “ The most profound technologies are those that disappear. They weave themselves into the fabric of everyday life until they are indistinguishable from it.”

  5. Limitations and Difficulties of Wireless • Mobility brings unique challenges of its own • Limitations from political and technical difficulties may inhibit wireless technologies (but doubtful today) • Lack of an industry-wide standard, which should be a concern to the global community (but the global economy will mandate a solution) • Device limitations • e.g., small LCD on a mobile telephone • e.g., browsers of most mobile wireless devices use wireless markup language (WML) instead of HTML • Security – Achilles heel of the technology • RF Effects – long term effects on humans? Environment?

  6. Why This Course? • A very hot technology • Wireless is convenient and less expensive, low deployment costs, great for countries without a wired infrastructure • Already an integral part of business and our lifestyle • Eventually everything will be wireless • A communications technique that will become fully integrated with our bodies in terms of our clothes and maybe even our brain! • Data rates are improving significantly faster than anticipated and in time will no longer be a limitation, especially when wireless data rates reach the processing bandwidth of the human eye

  7. Why Not This Course? • If it heats up quickly, it will also cool down just as fast (low specific heat) • Course time limitations limit development of a fundamental set of ‘knowledge’ tools. Limited hands-on opportunities. • Design, test and deployment is computer aided (as is everything today) and is very dynamic with new tools being introduced every day. • RF design is somewhat of a black art and not a large career field • Government is under pressure to open more spectrum for wireless applications (recent 108 MHz of analog TV channel spectrum, AT&T problems) – all leading to a very dynamic landscape. • What are the real job qualifications? Just about every engineering job will touch wireless communications in some manner. • Conclusions - Flexibility is the keynote of life. No substitute for experience.

  8. A Typical Tool:Wireless Communication System Design with MATLAB and Simulink • MathWorks algorithm development and system-level engineering tools: MATLAB and Simulink • Designing and testing the architecture and behavior of wireless devices early in the design process to reduce overall development time, cost, and risk • Lyrtech Signal Processing used for their SignalWAVe DSP/FPGA development hardware, a rapid-prototyping system with TI DSP and Xilinx FPGA. With Simulink, Xilinx System Generator for DSP and TI Code Composer Studio, SignalWAVe supports co-simulation, real-time processing, and hardware-in-the-loop • Design of wireless standards: 802.11a/b/g/n, WiMAX, Bluetooth • Design features include: Baseband DSP and RF equivalents, Behavioral analog/mixed-signal, MAC/Link layer

  9. Part One: Background • Provides preview and context for rest of book • Covers basic topics in Chapters 1 thru 4 • Data Communications • TCP/IP • Chapter 1 is the Introduction

  10. Chapter 2: Transmission Fundamentals • Basic overview of transmission topics • Data communications concepts • Includes techniques of analog and digital data transmission • Channel capacity • Transmission media • Multiplexing

  11. Chapter 3: Communication Networks • Comparison of basic communication network technologies • Circuit switching • Packet switching • Frame relay • ATM

  12. Chapter 4: Protocols and the TCP/IP Protocol Suite • Protocol architecture • Overview of TCP/IP • Open systems interconnection (OSI) reference model • Internetworking

  13. Part Two: Wireless Communication Technology • True start of the course • Underlying technology of wireless transmission • Encoding of analog and digital data for wireless transmission

  14. Chapter 5: Antennas and Propagation • Principles of radio and microwave • Antennas: radiation patterns, performance • Wireless transmission modes (propagation) • The harsh wireless environment: attenuation, fading, noise, absorption, multipath, data errors, interference • Compensation mechanisms (how computers can save the day)

  15. Chapter 6: Signal Encoding Techniques • Wireless transmission • Analog and digital data • Analog and digital signals • The large number of ways can you modulate a signal in the digital realm to convey information/data

  16. Chapter 7: Spread Spectrum • Advantages/Disadvantages • Frequency hopping (FHSS) • Direct sequence spread spectrum (DSSS) • Code division multiple access (CDMA)

  17. Chapter 8: Coding and Error Control • Using redundancy for error detection and correction • Forward error correction (FEC) • Automatic repeat request (ARQ) techniques

  18. Part Three: Wireless Networking • Examines major types of networks • Satellite-based networks • Cellular networks • Cordless systems • Fixed wireless access schemes • Use of mobile IP and Wireless Access Protocol (WAP) to provide Internet and Web access • WML – Wireless Markup Language

  19. Chapter 9: Satellite Communications • Quick run through of the material • Geostationary satellites (GEOS) • Medium-earth orbiting satellites (MEOS) • Low-earth orbiting satellites (LEOS) • Capacity allocation

  20. Chapter 10: Cellular Wireless Networks • Cellular wireless network design issues • First generation analog (traditional mobile telephony service) • Second generation digital cellular networks • Time-division multiple access (TDMA) • Code-division multiple access (CDMA) • 3G and 4G networks (G = generation) • How fast can it change? Sales hype? Speed is always the # 1 requirement. • In wireless networks, the crux has been that smaller is better (outside of the box thinking)

  21. Chapter 11: Cordless Systems and Wireless Local Loop • Quick run through of Chapter material • Cordless systems • Wireless local loop (WLL) • Sometimes called radio in the loop (RITL) or fixed wireless access (FWA)

  22. Chapter 12: Mobile IP and Wireless Access Protocol • IP protocol modifications to accommodate wireless access to Internet • Wireless Application Protocol (WAP) • Provides mobile users access to telephony and information services including Internet and Web • Includes wireless phones, pagers and personal digital assistants (PDAs)

  23. Part Four: Wireless Local Area Networks • Chapters 13 through 15 • Examines underlying wireless LAN technology • Examines standardized approaches to local wireless networking

  24. Chapter 13: Wireless LAN Technology • Overview of LANs and wireless LAN technology and applications • Transmission techniques of wireless LANs • Spread spectrum • Narrowband microwave • Infrared

  25. Chapter 14: Wi-Fi and the IEEE 802.11 Wireless LAN Standard • Wireless LAN standards defined by IEEE 802.11 committees • 802.11a – office LANs, up to 54 Mbps, 5 GHz • 802.11b – home LANs, up to 11 Mbps, 2.4 Ghz still the king because of deployed resources • 802.11g – 2.4 GHz, today’s high speed standard • 802.11n – 2.4/5 GHz multiple channels • Trend is toward equipment that does 802.11 a/b/g/n • Wi-Fi Protected Access (WPA, WPA2/AES) – improvement on the 802.11 security issues from WEP (Wired Equivalent Privacy) algorithm (64/128 bits)

  26. Chapter 15: Bluetooth and 802.15 • Bluetooth is an open specification for wireless communication and networking • Personal computers • Mobile phones • Other wireless devices • Consortium of companies under writing the cost of development and deployment • 802.15.3 – very high data rates for the short range electronic device interconnection

  27. Internet and Web Resources • Web page for this book • web sites. Listed by textbook chapter, errata sheet (make sure you select Errata-Wireless2e folder. Also textbook figures, tables, slides, internet mailing list, other wireless course sites. • Computer Science Student Support Site • • Good review topics, queuing theory, CS cheat sheet • Newsgroups/Newsletters/Outside Resources • Network Computing Mobile Observer • Refresher on electromagnetism (physics), the tutorials at

  28. Useful Web Sites from Stallings Chapter 1 – Introduction • IT World's Wireless: Provides a wide range of information on wireless technology, mostly from a management perspective. • Wireless Developer Network: News, tutorials, and discussions on wireless topics • Office of Spectrum Managment: responsible for managing the Federal Government's use of the radio frequency spectrum." There are many informative features on this Web site, including documents, links, and a frequency allocation chart.