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EE 6332, Spring, 2014 Wireless Telecommunication Systems. Zhu Han Department of Electrical and Computer Engineering Class 1 Jan. 13 rd , 2014. Outline. Instructor information Motivation to study wireless communications and networks Course descriptions and textbooks
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EE 6332, Spring, 2014Wireless Telecommunication Systems Zhu Han Department of Electrical and Computer Engineering Class 1 Jan. 13rd, 2014
Outline • Instructor information • Motivation to study wireless communications and networks • Course descriptions and textbooks • What you will study from this course • Objectives • Coverage and schedule • Homework, projects, and exams • Other policies • Reasons to be my students • Introduction to wireless networks
Instructor Information • Office location: Engineering Building II W302 • Office hours: Mon. 1:00pm - 4:00pm, or by appointment • Email: zhan2@uh.edu hanzhu22@gmail.com • Phone: 713-743-4437(o) /301-996-2011(c) • Course website: http://www2.egr.uh.edu/~zhan2/ECE6332 • TA: ??? • Research interests: Wireless Networking, Signal Processing and Security http://wireless.egr.uh.edu/
Motivations • Recent Development • Cellular system: 3G, 4G, video, game, • WIFI everywhere • WIMAX, next generation metropolitan web for business • UWB, no cables • Bluetooth, small devices connections • Job Market • Probably one of most easy and high paid majors recently • Many companies in town or Dallas/Austin • Research Potential • One-to-one communication has less room to go, but multiuser communication is still an open issue.
Course Objective • Past decade has seen a surge of research activities in the field of wireless communication. • Emerging from this research thrust are new points of view on how to communicate effectively over wireless channels. • The goal of this course is to study in a unified way the fundamentals as well as the new research developments. • The concepts are illustrated using examples from several modern wireless systems (GSM, IS-95, CDMA 2000 1x EV-DO, Flarion's Flash OFDM, ArrayComm systems.)
Course Descriptions • What is the wireless communication system? • What are the wireless channels? • What are the theorems? • What are the major components and techniques? • How is the information transmitted? • What are the current industrial standards? • What are the state-of-art research? • Can I find a job by studying this course? • Can I find research topics?
Textbook and Software • Require textbook: Andrea Goldsmith, Wireless Communication. Cambridge Univ. Press 2005. • Optional testbook David Tse and Pramod Viswanath, Fundamentals of Wireless Communication. Cambridge University Press, 2005 • Require Software: MATLAB; • Recommended readings • Digital communications: J. Proakis, Digital Communications • Random process: G.R. Grimmett and D.R. Stirzaker, Probability and Random Processes • Estimation and detection: H.V. Poor, An introduction to Signal Detection and Estimation • Information theory: T. M. Cover and J. A. Thomas, Elements of Information Theory • Error correct coding: P.Sweeney, Error Control Coding • Computer Networks: A. S. Tanenbaum, Computer Networks
Schedule • Overview • Wireless Channel • Capacity (important, black board) • Digital Modulation • Coding (important black board) • Adaptive modulation and coding • Diversity and MIMO • Equalization • OFDM • CDMA • Wireless Networking • Slides and black board • For unimportant chapters, might not fully follow the book.
Homework, Project, and Exam • Homework • 3~4 sets • Rules: 50% off if late. 0% is 2 week late • Exams • Two exams • Team Project • 2~3 people, related topics, presentation, and term paper • Schedule next week • Participations • Attendance and Feedback • Invited Talks for 2 missing class due to conference • Votes for the percentages for homework, projects, and exams
Teaching Styles • black board plus Slides • Slides can convey more information in an organized way • Blackboard is better for equations and prevents you from not coming. • A lesson from last semester: math • Course Website • Print handouts with 3 slides per page before you come • Homework assignment and solutions • Project descriptions and preliminary codes • Feedback • Too fast, too slow, small class advantages. • Presentation, English, …
Other Policies Any violation of academic integrity will receive academic and possibly disciplinary sanctions, including the possible awarding of an XF grade which is recorded on the transcript and states that failure of the course was due to an act of academic dishonesty. All acts of academic dishonesty are recorded so repeat offenders can be sanctioned accordingly. • CHEATING • COPYING ON A TEST • PLAGIARISM • ACTS OF AIDING OR ABETTING • UNAUTHORIZED POSSESSION • SUBMITTING PREVIOUS WORK • TAMPERING WITH WORK • GHOSTING or MISREPRESENTATION • ALTERING EXAMS • COMPUTER THEFT
Reasons to be my students • Wireless Communication and Networking have great market • Usually highly paid and have potential to retire overnight • Highly interdisciplinary • Do not need to find research topics which are the most difficult part. • Research Assistant, Stipend • Free trips to conferences in China, Hawaii, Europe, Australia, South Africa, Miami… • A kind of nice (at least looks like) • Work with hope and happiness • Graduate fast
History of Telecommunication • Prehistoric: Fires, Beacons, Smoke signals • 6th century BC: Mail • 5th century BC: Pigeon post • 4th century BC: Hydraulic semaphores • 490 BC: Heliographs • 15th century AD: Maritime flags • 1790 AD: Semaphore lines • 19th century AD: Signal lamps
History of Telecommunication • Audio signals: • Prehistoric: Communication drums, Horns • 1838 AD: Electrical telegraph. See: Telegraph history. • 1876: Telephone. See: Invention of the telephone, History of the telephone, Timeline of the telephone • 1880: Photophone • 1896: Radio. See: History of radio. • Advanced electrical/electronic signals: • 1927: Television. See: History of television • 1930: Videophone • 1964: Fiber optical telecommunications • 1969: Computer networking • 1981: Analog cellular mobile phones • 1982: SMTP email • 1983: Internet. See: History of Internet • 1998: Satellite phones
WiFi WiFi 802.11g/n satellite WiFi UWB bluetooth WiFi cellular At Home
At Home Source: http://teacher.scholastic.com/activities/science/wireless_interactives.htm
At Home: Last-Mile • Many users still don’t have broadband • reasons: out of service area; some consider expensive • Broadband speed is still limited • DSL: 1-6 Mbps download, and 100-768Kbps upload • Cable modem: depends on your neighbors • Insufficient for several applications (e.g., high-quality video streaming)
On the Move Source: http://www.ece.uah.edu/~jovanov/whrms/
On the Move: Context-Aware Source: http://www.cs.cmu.edu/~aura/docdir/sensay_iswc.pdf
On the Road GSM/UMTS, cdmaOne/cdma2000,WLAN, GPS DAB, TETRA, ... ad hoc road condition, weather, location-based services, emergency
Example: IntelliDrive (Vehicle Infrastructure Integration) • Traffic crashes resulted in more than 41,000 lives lost in 2007 • Establishing vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I) and vehicle-to-hand-held-devices (V2D) communications • safety: e.g., intersection collision avoidance/violation warning/turn conflict warning, curve warning • mobility: e.g., crash data, weather/road surface data, construction zones, emergency vehicle signal pre-emption More info: http://www.its.dot.gov/intellidrive/index.htm
Collision Avoidance : V2V Networks • stalled vehicle warning • bland spots http://www.gm.com/company/gmability/safety/news_issues/releases/sixthsense_102405.html
Collision Avoidance at Intersections • Two million accidents at intersections per year in US Source: http://www.fhwa.dot.gov/tfhrc/safety/pubs/its/ruralitsandrd/tb-intercollision.pdf
Mobile and Wireless Services – Always Best Connected UMTS Rel. 5 400 kbit/s LAN 100 Mbit/s, WLAN 54 Mbit/s GSM 53 kbit/s Bluetooth 500 kbit/s LAN, WLAN 780 kbit/s UMTS, DECT 2 Mbit/s GSM/EDGE 135 kbit/s, WLAN 780 kbit/s UMTS Rel. 6 400 kbit/s GSM 115 kbit/s, WLAN 11 Mbit/s
Disaster Recovery/Military • 9/11, Tsunami, Hurricane Katrina, South Asian earthquake … • Wireless communication andmobile computing capabilitycan make a difference between life and death ! • rapid deployment • efficient resource and energy usage • flexible: unicast, broadcast, multicast, anycast • resilient: survive in unfavorable and untrusted environments http://www.att.com/ndr/
Patch Network Gateway Transit Network Basestation Habitat Monitoring: Example on Great Duck Island A 15-minute human visit leads to 20% offspring mortality
Challenge 1: Unreliable and Unpredictable Wireless Coverage • Wireless links are not reliable: they may vary over time and space Reception v. Distance Asymmetry vs. Power *Cerpa, Busek et. al What Robert Poor (Ember) calls “The good, the bad and the ugly”
Challenge 2: Open Wireless Medium • Wireless interference • Hidden terminals and • Exposed terminal • Wireless security • eavesdropping, denial of service, … R1 S1 S2 R1 S1 R1 R2 R1 S1 S2 R2
Challenge 3: Mobility • Mobility causes poor-quality wireless links • Mobility causes intermittent connection • under intermittent connected networks, traditional routing, TCP, applications all break • Mobility changes context, e.g., location
PDA phone • data • simpler graphical displays • 802.11/3G Sensors, embedded controllers Challenge 4: Portability • Limited battery power • Limited processing, display and storage Laptop • fully functional • standard applications • battery; 802.11 Mobile phones • voice, data • simple graphical displays • GSM/3G Performance/Weight/Power Consumption
Challenge 5: Changing Regulation and Multiple Communication Standards cordlessphones wireless LAN cellular phones satellites 1980:CT0 1981: NMT 450 1982: Inmarsat-A 1983: AMPS 1984:CT1 1986: NMT 900 1987:CT1+ 1988: Inmarsat-C 1989: CT 2 1991: CDMA 1991: D-AMPS 1991: DECT 199x: proprietary 1992: GSM 1992: Inmarsat-B Inmarsat-M 1993: PDC 1997: IEEE 802.11 1994:DCS 1800 1998: Iridium 1999: 802.11b, Bluetooth 2000: IEEE 802.11a 2000:GPRS analogue 2001: IMT-2000 digital Fourth Generation (Internet based)
Wireless Technologies WAN (Wide Area Network) MAN (Metropolitan Area Network) LAN (Local Area Network) PAN (Personal Area Network)
Mobile Station • MP3, GPS, vending machine UMPC
Base Station Cheaper, denser, smaller
WMAN/WiMax Structure • Replace cable or low speed fiber in the last mile
Comparison of 802.11 Standards • g is back compatible with b. but b is supported by Intel • CDMA vs. OFDM • Free WIFI in SF • Contention based multiple access • 802.11AC
Personal Area Networks • 802.15: 4m-10m • Master-slave piconets • Capable of connecting a mix of multiple piconets into “scatternet” • Service discovery protocol allows invisible interaction of various “trusted” devices • Less susceptible to interference
Bluetooth • Wireless PAN • 2.4GHz band with 1Mbps speed • Spread spectrum frequency-hopping • “always on” user-transparent cable-replacement • Combination of packet-switching & circuit-switching (good for data & voice) • 3 voice channels - 64Kbps each • Low power, low cost • Transparently connects “office” devices • Laptop, Desktop, PDA, Phone, printer • Bridging capability: network-pda-phone • Zigbee: low power devices
Ultra Wide Band • High speed at short range: • 480 Mb/s at ~3m. Does not penetrate walls • Bandwidth >500MHz • Very low power density • Wireless USB • HDTV connection • CDMA vs. OFDM
Comparison • Speed and Range
Ad Hoc Network • Mobile Ad Hoc Networks (MANETs) • An autonomous collection of mobile users that communicate over relatively bandwidth constrained wireless links. • Since the nodes are mobile, the network topology may change rapidly and unpredictably over time. • The network is decentralized, where all network activity including discovering the topology and delivering messages must be executed by the nodes themselves. MANETs need efficient distributed algorithms to determine network organization, link scheduling, and routing. • The set of applications for MANETs is heterogeneous, ranging from small, static networks that are constrained by power sources, to large-scale, mobile, highly dynamic networks • In a military environment, preservation of security, latency, reliability, intentional jamming, and recovery from failure are significant concerns
MANET Examples • Ad hoc mode of WIFI • Military • Infrastructure-less
Cognitive Radio • Software radio • Can change modulation carrier frequency to different service providers • Cognitive radio with cognitive ability
Network Network The Layered Reference Model Application Application Transport Transport Network Network Data Link Data Link Data Link Data Link Physical Physical Physical Physical Medium Radio Often we need to implement a function across multiple layers.
GPS Position • By knowing how far one is from three satellites one can ideally find their 3D coordinates • To correct for clock errors one needs to receive four satellites • Differential GPS: local FM