1 / 59

Wireless Communication

Wireless Communication. Background of Wireless Communication. Wireless Communication Technology. Wireless Networking and Mobile IP. Wireless Local Area Networks. Student Presentations and Projects. Introductory Lecture. Objectives.

amanda-conway
Télécharger la présentation

Wireless Communication

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Wireless Communication Background of Wireless Communication Wireless Communication Technology Wireless Networking and Mobile IP Wireless Local Area Networks Student Presentations and Projects Introductory Lecture

  2. Objectives • Where is Wireless Communication today? Where has it come from in the last decade? What is its future potential? • Why is wireless channel different from wired? • How does wireless design overcome the challenges of the channels and interference? • What are key wireless communication concepts? • Rapid fire introduction to buzz words and why they matter: OFDM/CDMA/MIMO … • How do they feature in modern/emerging wireless systems (Wifi: 802.11a/b/g/n, 3G, mobile WIMAX: 802.16e)? • Mobile Ad hoc and sensor networks are covered at the end of course …

  3. Wireless Comes of Age • Guglielmo Marconi invented the wireless telegraph in 1896 • Communication by encoding alphanumeric characters in analog signal • Sent telegraphic signals across the Atlantic Ocean • Communications satellites launched in 1957 • Advances in wireless technology • Radio, television, mobile telephone, communication satellites • More recently • Satellite communications, wireless networking, cellular technology

  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 • Services can be deployed faster than fixed services • No cost of cable plant • Service is mobile, deployed almost anywhere • Wireless is convenient and less expensive

  5. Limitations and Difficulties of Wireless Technologies • Limitations and political and technical difficulties inhibit wireless technologies • Lack of an industry-wide standard • Device limitations • E.g., small LCD on a mobile telephone can only displaying a few lines of text • E.g., browsers of most mobile wireless devices use wireless markup language (WML) instead of HTML

  6. Part One: Chapter 1: Introduction • Provides preview and context for rest of the course • Covers basic topics • Data Communications • TCP/IP

  7. 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

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

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

  10. Part Two: Wireless Communication Technology • Underlying technology of wireless transmission • Encoding of analog and digital data for wireless transmission

  11. Chapter 5: Antennas and Propagation • Principles of radio and microwave • Antenna performance • Wireless transmission modes • Fading

  12. Chapter 6: Signal Encoding Techniques • Wireless transmission • Analog and digital data • Analog and digital signals

  13. Chapter 7: Spread Spectrum • Frequency hopping • Direct sequence spread spectrum • Code division multiple access (CDMA)

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

  15. 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

  16. Chapter 9: Satellite Communications • Geostationary satellites (GEOS) • Low-earth orbiting satellites (LEOS) • Medium-earth orbiting satellites (MEOS) • Capacity allocation

  17. 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) • Third generation networks

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

  19. Chapter 12: Mobile IP and Wireless Access Protocol • Modifications to IP protocol 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)

  20. Part Four: Wireless Local Area Networks • Examines underlying wireless LAN technology • Examines standardized approaches to local wireless networking

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

  22. Chapter 14: IEEE 802.11 Wireless LAN Standard • Wireless LAN standards defined by IEEE 802.11 committee

  23. Chapter 15: Bluetooth • Bluetooth is an open specification for wireless communication and networking • Personal computers • Mobile phones • Other wireless devices

  24. Wireless Ad hoc Networks • Wireless Ad hoc Networks is a specific type of Wireless networks when no infrastructure exists • Multi-hop Ad hoc Networks • Sensor Networks • Routing • Security • Applications

  25. Internet and Web Resources • Course Website • http://web.uettaxila.edu.pk/cms/teWCbs • Lectures, Labs, Assignments, Quizzes, Other Info • Web page for the course text book • http://www.williamstallings.com/Wireless/Wireless2e.htmlUseful web sites, errata sheet, figures, tables, slides, internet mailing list, wireless courses • Computer Science Student Support Site • http://www.williamstallings.com/StudentSupport.html • Newsgroups • comp.std.wireless • comp.dcom.*

  26. Text Books • Wireless Communications and Networks, Second Edition by William Stallings • Fundamentals of Wireless Communication by David Tse and Pramod Viswanath

  27. Wireless Communication: Potential

  28. Why Wireless? • Characteristics • Mostly radio transmission, new protocols for data transmission are needed • Advantages • Spatial flexibility in radio reception range • Ad hoc networks without former planning • No problems with wiring (e.g. historical buildings, fire protection, esthetics) • Robust against disasters like earthquake, fire – and careless users which remove connectors! • Disadvantages • Generally very low transmission rates for higher numbers of users • Often proprietary, more powerful approaches, standards are often restricted • Many national regulations, global regulations are evolving slowly • Restricted frequency range, interferences of frequencies • Nevertheless, in the last 10-20 years, it has really been a wireless revolution…

  29. The Wireless Revolution • Cellular is the fastest growing sector of communication industry (exponential growth since 1982, with over 2 billion users worldwide today) • Three generations of wireless • First Generation (1G): Analog 25 or 30 KHz FM, voice only, mostly vehicular communication • Second Generation (2G): Narrowband TDMA and CDMA, voice and low bit-rate data, portable units. 2.5G increased data transmission capabilities • Third Generation (3G): Wideband TDMA and CDMA, voice and high bit-rate data, portable units • Fourth Generation (in progress): true broadband wireless: WIMAX, 3G LTE, 802.11 a/b/g/n

  30. The Wireless Communication Opportunity Demand Gap Wireless mobile services grew from 11 million subscribers worldwide in 1990 to over 2 billion in 2005. In the same period, the Internet grew from being a curious academic tool to about 1 billion users. Broadband internet access is also growing rapidly

  31. Sept 2006 figures: 2.53 Billion total; 2.02 B (GSM), 320 M (CDMA), 81.2M UMTS Source: http://www.3gamericas.org/English/Statistics/

  32. Source: Pyramid Research WLAN Market: WiFi • WLAN Growth Drivers • Convenience & Flexibility • Productivity Gains • Low Cost • Embedded WLAN Source: AirTight Networks

  33. Wireless: The Big Picture…

  34. Wireless: Understanding the Big Picture… • Wireless (vs wired)… communication medium • Cellular (vs meshed vs MANETs)…architectures for coverage, capacity, QoS, mobility, auto-configuration, infrastructure support • Mobile (vs fixed vs portable)… implications for devices: phone vs PSP vs PDA vs laptop vs ultramobile • WAN (vs WLAN vs WMAN)…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…

  35. Mobile Computing/Entertainment/Commns • Computing: smaller, faster • Disks: larger size, small form • Communications: wireless voice, data • Multimedia integration: voice, data, video, games iPoD: impact of disk size/cost Samsung Cameraphone w/ camcorder SONY PSP: mobile gaming Blackberry: phone + PDA

  36. Variety of Wireless-Capable Devices 2006 Thanksgiving sales: < $1000 Plasma 42” TVs. These will soon be wireless-broadband enabled and can play home movies/videos from the Internet

  37. Walled Garden Emerging Rich Media Broadband Wireless Broadband Wireless/Wireline LAN Cellular Rich Media Broadband Wireless Value Added Services Internet Access Services *Other brands and names are the property of their respective owners.

  38. 3G LTE/WiMAX WiFi Converging Markets Drive Economies of Scale CE devices will require low cost WLAN/WWAN access ~220M BB users (CBL+DSL+other) Market demand is >1B WLAN BWA 3GPP/2 CE 200 M units a year growing at 35% >$1B market growing into cable and DSL markets $>600B market>2 B users>700M units/yr 250M devices in ‘09 with a need for access Converged Markets addressing Mobile WWAN WiFi/WiMax or WiFi/3G integration will bridge markets Source: Intel Estimates, IDC,

  39. Mainstream Mobile Broadband Internet Will Also Require: Innovation in Distribution: Single Chip WiFi + WiMAX/3Gfor Mass Market Innovation in Services: Web 2.0, AJAX, Personal Internet Innovation in Billing: Pay as You Go, Pre-paid, or Monthly Subscription * Other names and brands may be claimed as the property of others

  40. Wireless History (Brief)

  41. Wireless History 1901: First radio reception across the Atlantic Ocean 1924: First Mobile Radio Telephone

  42. Early Cellular Systems • 1940s-50s: cellular concept discovered (AT&T) • 1st Generation: Analog: • AMPS: FDMA with 30 KHz FM-modulated voice channels. • 1983: The first analog cellular system deployed in Chicago: saturated by 1984, • FCC increased the cellular spectral allocation from 40 MHz to 50 MHz. • Two 25MHz channels: DL and UL (FDD) • AT&T moved on to fiber optics in ‘80s. • 2nd generation: digital: early 90s • higher capacity, improved cost, speed, and power efficiency of digital hardware

  43. Wireless Timeline (Partial) • 1991 - Specification of DECT (cordless phone) • Digital European Cordless Telephone (today: Digital Enhanced Cordless Telecommunications). Other cordless standards: PHS (Japan), CT-2 (Europe/Asia) • 1880-1900MHz, ~100-500m range, 120 duplex channels, 1.2Mbit/s data transmission, voice encryption, authentication, up to several 10000 user/km2, used in more than 50 countries. • 1992 - Start of GSM • In Germany as D1 and D2, fully digital, 900MHz, 124 channels • Automatic location, hand-over, cellular • Roaming in Europe - now worldwide in more than 170 countries • Services: data with 9.6kbit/s, FAX, voice, ... • 1996 - HiperLAN (High Performance Radio Local Area Network) • ETSI, standardization of type 1: 5.15 - 5.30GHz, 23.5Mbit/s • Recommendations for type 2 and 3 (both 5GHz) and 4 (17GHz) as wireless ATM-networks (up to 155Mbit/s) • 1997 - Wireless LAN – IEEE 802.11 • IEEE standard, 2.4 - 2.5GHz and infrared, 2Mbit/s • Already many (proprietary) products available in the beginning • 1998 - Specification of GSM successors • UMTS (Universal Mobile Telecommunication System) as European proposals for IMT-2000 • Iridium: 66 satellites (+6 spare), 1.6GHz to the mobile phone

  44. Wireless Timeline (Partial) • 1999 - Standardization of additional wireless LANs • IEEE standard 802.11b, 2.4-2.5GHz, 11Mbit/s • Bluetooth for piconets, 2.4Ghz, <1Mbit/s • Decision about IMT-2000 • Several “members” of a “family”: UMTS, cdma2000, DECT, … • Start of WAP (Wireless Application Protocol) and i-mode • Access to many (Internet) services via the mobile phone • 2000 - GSM with higher data rates • HSCSD offers up to 57,6kbit/s • First GPRS trials with up to 50 kbit/s (packet oriented!) • GSM Enhancements for data transmission pick up (EDGE, GPRS, HSCSD) • UMTS auctions/beauty contests • Hype followed by disillusionment (approx. 50 B$ payed in Germany for 6 UMTS licenses!) • 2001 - Start of 3G systems • Cdma2000 in Korea, UMTS in Europe, Foma (almost UMTS) in Japan • 2002 – Standardization of high-capacity wireless networks • IEEE 802.16 as Wireless MAN

  45. Broadband Wireless Milestones: Summary Source: J.Andrews, A. Ghosh, R. Muhamed, Fundamentals of WIMAX

  46. Wireless Systems: From Narrowband to Broadband

  47. What do service providers need? • Highest possible consumer satisfaction… • QoS is primary requirement – video and high throughput (mobile) data sessions • Management capability to the devices: easy service provisioning, billing. • Secure mobility support: Handoff & Mesh • Avoid theft-of-service • New services…

  48. What do Home users want? • Range: reliable wireless networking throughout the home • High fidelity A/V: good Quality of Service for high quality audio and video • Throughput! • HDTV-720 in the US @ 16 Mbps (MPEG2) • HDTV-1080 in Japan @ 20 Mbps (MPEG2) • Next generation Media Center will support 2 concurrent video streaming, and by .11n ratification 4 concurrent streaming • For 3 streams in the home, with picture-in-picture, and Internet access, 100Mbps UDP level throughput is easily consumed

  49. Modern Wireless Systems Peak

  50. Modern Wireless Systems (by Segment)

More Related