TEL 428E Wireless Communica5on Networks İstanbul Teknik Üniversitesi Elektrik Elektronik Fakültesi Elektronik Haberleşme Mühendisliği Spring 2015 Course Informa5on • Instructor Güneş Karabulut Kurt Room # 3213 (212) 285 3509 gkurt@itu.edu.tr 2 Course Informa5on • Time Slot Mondays 09.30 – 12.30 • Office Hours Tuesdays 10.00-­‐12.00 • Course Loca5on 2102 Web Site: NINOVA 3 What you need to know? • Digital Communica5on Systems • Probability Theory • Basic Programming Skills (object oriented programming -­‐ Java) 4 What you’ll learn in TEL-­‐428? • Introduc5on to wireless communica5on networks and mobile compu5ng. • Network architectures and components. • Revision of physical layer concepts. • Medium access control (MAC), network and transport layers. • Quality of service (QoS), security and authen5ca5on management. • Mobility support and mobile compu5ng in wireless communica5on networks. • Network performance evalua5on. • Wireless local area networks and cellular networks. Asking ques5ons is the key to learning !!! 5 Resources • Textbook – Mobile Communica5ons, Jochen Schiller, Addison-­‐Wesley, 2nd Ed., 2003. • Supplementary Material: – Wireless Communica5ons & Networks, William Stallings, Pren5ce Hall, 2nd Edi5on, 2004 – Wireless Communica5ons: Principles & Prac5ce, Theodore S. Rappaport, Pren5ce Hall, 2002. ISBN 0-­‐13-­‐042232-­‐0. – Resource, Mobility and Security Management in Wireless Networks and Mobile Communica5ons. Editor(s): Honglin Hu, Yan Zhang, Masayuki Fujise, CRC Press, 2006. – Wireless Quality of Service: Techniques, Standards, and Applica5ons Editor(s): Maode Ma, Mieso K. Denko, CRC Press, 2008. – Mobile Compu5ng Handbook, Editor(s): Mohammad Ilyas, Boca Raton, Imad Mahgoub, CRC Press, 2004. Addi$onal material will be cited during the course. 6 Evalua5on Methodology • Course Project (40 %) –
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(5%) March 4, 2013 Progress Report (5 %) April 1, 2013 Final Report (15 %) May 13, 2013 Demonstra$on (15 %) May 13, 2013 • Midterm Exams (20 %) – March 25, 2013 – April 22, 2013 • Final Exam (40 %) TBA To take the final exam you need to: 1. Submit a project 2. Have an average exceeding 30 % 7 Mobile Compu5ng (Wikipedia) • Mobile compu,ng is a form of human–computer interac5on where a computer is expected to be transported during normal usage. • Mobile compu5ng has three aspects: mobile communica5on, mobile hardware and mobile souware. – The first aspect addresses communica5on issues in ad-­‐hoc and infrastructure networks as well as communica5on proper5es, protocols, data formats and concrete technologies. – The second aspect focuses on the hardware, i.e. mobile devices or device components. – The third aspect deals with the characteris5cs and requirements of mobile applica5ons. 8 Challenges of Mobile Compu5ng • Bandwidth – Scarce spectrum • Leading to low data rates • Power – Mobility based constraints on bavery • Reliability – Wireless channel is 5me varying • High loss rates • Security – Informa5on is broadcast More info @ //citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.48.1636 9 Informa5on about Project • This course will combine in-­‐class lectures with design and development of a mobile compu5ng applica5on of the students' own choosing using Android opera5ng system. • Project objec5ve: – To design a func5oning mobile compu5ng applica5on 10 Spring’15 Project Theme • Smart homes/smart buildings – &they are gezng smarter • Smart door locks – open with a touch • Smart cooking ranges – with built-­‐in tablets that enable remote control—which will even text you when dinner’s ready • voice-­‐ac5vated barbecue grill 11 Why Android? •
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Android is a mobile opera5ng system ini5ally developed by Android Inc. Android was bought by Google in 2005. Android is based upon a modified version of the Linux kernel. The Android Open Source Project (AOSP) is tasked with the maintenance and further development of Android. In Q4 2010 the Android O.S. was the world's best-­‐selling smartphone pla|orm, dethroning Nokia's Symbian from the 10 year top posi5on (Canalys). «Developing mobile applica5ons today for Android is easier than it was for J2me in the late 1990s and early 2000-­‐2001.» (SOURCE) 12 Project Proposal • Up to 3 students are allowed to work together on a term project. • A 1-­‐2-­‐paragraph project proposal describing the mo5va5on and func5onali5es of the mobile compu5ng applica5on is due on March 2nd. • The project proposal should include a fairly detailed descrip5on of what you plan to do. 13 Progress Report • DEADLINE: March 30th • Contents: – Project Descrip5on – Progress Table ITEM NUMBER WORK RELATION WITH THE RESOURCES DURATION (PEOPLE + DESCRIPTION PROJECT HARDWARE ...) 1 2 3 – References 14 Project Report • FINAL REPORT (DUE May 4) – The final report should follow one of the formazng styles in IEEE Transac5ons/Journal/Magazine/Levers. – The report should demonstrate in-­‐depth understanding of the design and present key technical considera5ons in the issues involved. – It must include • An abstract describing your main work • An introduc5on describing the problem being addressed; • In-­‐depth technical descrip5ons including –
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Exis5ng solu5ons, problem modeling and solu5ons, systems design considera5ons and trade offs, applica5on range and current implementa5on status, future work; • Final summary • Generated code 15 WEEK DATE Course Outline 2 Feb. 09 Introduc5on 3 Feb. 16 Wireless Transmission 4 Feb. 23 Outlook + Android Tutorial (Guest Speaker) 5 Mar. 2 Medium Access Control (Project Proposal) 6 Mar. 9 Network Layer 7 Mar. 16 Transport Layer (Project Session # 1) 8 Mar. 23 Midterm Exam 9 Mar. 30 Security & Authen5ca5on (Progress Report) 10 Apr. 6 11 Apr. 13 Performance Metrics, Measurement and Management 12 Apr. 20 Cellular Networks (2G/3G) (Project Session # 3) 13 Apr. 27 Wireless Local Area Networks 14 May 4 Mobility Managament (Project Session # 2) Project Workshop (Final Report) 16 Basic Communica5on System Communica,on is the process of conveying informa5on from a sender to a receiver with the use of a medium in which the communicated informa5on is understood by both sender and receiver. (Source: Wikipedia) Transmiver Channel Receiver 17 Wired vs. Wireless Wired Wireless • Low avenua5on • Low 5me-­‐variance • Negligible interference • Avenua5on is high • Time-­‐varying • High interference – Each wire is well isolated • Costly • No mobility – Single medium • No digging to lay cables • Nomadic vs. Mobile (?) 18 History of wireless comm. Before the “Birth of Radio”, 1867-­‐1896 1867 -­‐ Maxwell predicts existence of electromagne5c (EM) waves 1887 -­‐ Hertz proves existence of EM waves; first spark transmiver generates a spark in a receiver several meters away • 1890 -­‐ Branly develops coherer for detec5ng radio waves • 1896 -­‐ Guglielmo Marconi demonstrates wireless telegraph to English telegraph office • “The Birth of Radio” • 1897 -­‐ Marconi awarded patent for wireless telegraph • 1897 -­‐ First “Marconi sta5on” established on Needles island to communicate with English coast • 1898 -­‐ Marconi awarded English patent for tuned communica5on • 1898 -­‐ Wireless telegraphic connec5on between England and France established •
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19 History of wireless comm. Transoceanic Communica,on 1901 -­‐ Marconi successfully transmits radio signal across Atlan5c Ocean from Cornwall to Newfoundland • 1902 -­‐ First bidirec5onal communica5on across Atlan5c • 1909 -­‐ Marconi awarded Nobel prize for physics • Voice over Radio • 1914 -­‐ First voice over radio transmission • 1920s -­‐ Mobile receivers installed in police cars in Detroit • 1930s -­‐ Mobile transmivers developed; radio equipment occupied most of police car trunk • 1935 -­‐ Frequency modula5on (FM) demonstrated by Armstrong • 1940s -­‐ Majority of police systems converted to FM •
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Birth of Mobile Telephony 1946 -­‐ First interconnec5on of mobile users to public switched telephone network (PSTN) 1949 -­‐ FCC recognizes mobile radio as new class of service 1940s -­‐ Number of mobile users > 50K 1950s -­‐ Number of mobile users > 500K 1960s -­‐ Number of mobile users > 1.4M 1960s -­‐ Improved Mobile Telephone Service (IMTS) introduced; supports full-­‐duplex, auto dial, auto trunking 1976 -­‐ Bell Mobile Phone has 543 pay customers using 12 channels in the New York City area; wai5ng list is 3700 people; service is poor due to blocking 21 Range of Wireless Systems Satellite
FM, MW, SW Radio
Cellular Systems
Bluetooth
Infra-red
1m 10m PAN
100m LAN
1km 10km MAN
100km WAN
22 Electro-­‐Magne5c Spectrum The electromagne5c (EM) spectrum is the range of all possible electromagne5c radia5on. (Souce: Wikipedia) Visible light, is electromagne5c radia5on of a wavelength that is visible to the human eye (about 400–700 nm), or up to 380–750 nm 23 Regula5ons • Türkiye – Bilgi Teknolojileri ve İle5şim Kurumu (BTK) – www.tk.gov.tr • United States – Federal Communica5ons Commission (FCC) – www.fcc.gov • United Kingdom – Office of Communica5ons (OFCOM) – www.ofcom.org.uk 24 Frequency Alloca5ons 25 Frequency Alloca5ons -­‐ BTK 26 Underlying concepts • Electromagne5cs – Antennas, wave propaga5on, channel modeling • Signals and systems – Filtering, Fourier transforms, block-­‐diagram design • Digital signal processing – Equaliza5on, spread-­‐spectrum, source coding • Communica5ons – Modula5on, noise analysis, channel capacity, channel coding 27 Enabling technologies • Digital integrated circuits • RF genera5on devices (efficient power amps, sleep modes, improved oscillators, smart antennas) • Source coding (data compression) • Modula5on (improved efficiency) • Mul5ple-­‐access techniques (increase number of users) • Channel coding/forward error correc5on (improve probability of successful recep5on) • Souware programmable radios 28 Mobile vs. Portable • There are two different kinds of mobility: user mobility and device portability. – User mobility refers to a user who has access to the same or similar telecommunica5on services at different places, i.e., the user can be mobile, and the services will follow him or her. – With device portability, the communica5on device moves (with or without a user). Many mechanisms in the network and inside the device have to make sure that communica5on is s5ll possible while the device is moving. • A typical example for systems suppor5ng device portability is the mobile phone system, where the system itself hands the device from one radio transmiver (also called a base sta5on) to the next if the signal becomes too weak. 29 Communica5on Devices •
Fixed and wired: – The typical desktop computer in an office. – Neither weight nor power consump5on of the devices allow for mobile usage. • The devices use fixed networks for performance reasons. •
Mobile and wired: – Many of today’s laptops fall into this category; – users carry the laptop from one hotel to the next, reconnec5ng to the company’s network via the telephone network and a modem. •
Fixed and wireless: – This mode is used for installing networks, e.g., in historical buildings to avoid damage by installing wires, or at trade shows to ensure fast network setup. •
Mobile and wireless: – No cable restricts the user, who can roam between different wireless networks. – Today’s most successful example for this category is GSM & its evolu5on with 4 billion (!) users. 30 Applica5ons Vehicles, emergencies, businesses, infotainment, loca5on based services, device market ... 31 Mobile User Trends -­‐ EUROPE 1000 900 800 Million Users 700 600 Cellphone 500 Fixed Phone 400 BB Internet 300 200 100 0 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 SOURCE: //www.itu.int/ITU-D/ict/statistics/
32 Mobile User Trends -­‐ TURKEY 70 60 Million Users 50 40 Cellphone Fixed Phone 30 BB Internet 20 10 0 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 SOURCE: //www.itu.int/ITU-D/ict/statistics/
33 Network Model Research Ques,on: Why do we have 5 layers instead of 7 as recommended by OSI? 34 Physical layer (PHY) • The lowest layer in a communica5on system • Responsible for the conversion of a stream of bits into signals that can be transmived on the sender side. • The physical layer of the receiver then transforms the signals back into a bit stream. • For wireless communica5on, the physical layer is responsible for frequency selec5on, genera5on of the carrier frequency, signal detec5on (although heavy interference may disturb the signal), modula5on of data onto a carrier frequency and (depending on the transmission scheme) encryp5on. 35 Data link layer (DLL) • The main tasks of this layer include accessing the medium, mul5plexing of different data streams, correc5on of transmission errors, and synchroniza5on (i.e., detec5on of a data frame). • The data link layer is responsible for a reliable point-­‐to point connec5on between two devices or a point-­‐to-­‐mul5point connec5on between one sender and several receivers. 36 Network layer • Responsible for rou5ng packets through a network or establishing a connec5on between two en55es over many other intermediate systems. • Important topics are addressing, rou5ng, device loca5on, and handover between different networks. 37 Transport layer • This layer is used in the reference model to establish an end-­‐to-­‐end connec5on. • Topics like quality of service (QoS), flow and conges5on control are relevant, especially if the transport protocols known from the Internet, TCP and UDP, are to be used over a wireless link. 38 Applica5on layer • The applica5ons (complemented by addi5onal layers that can support applica5ons) are situated on top of all transmission oriented layers. • Topics of interest in this context are service loca5on, support for mul5media applica5ons, adap5ve applica5ons that can handle the large varia5ons in transmission characteris5cs, and wireless access to the world wide web using a portable device. • Very demanding applica5ons are video (high data rate) and interac5ve gaming (low jiver, low latency). Your’s to discover J 39 Resources • Challenges of mobile compu5ng, G. H. Forman & J. Zahorjan • Textbook: Chapter 1 Quiz -­‐1 deadline 16/02 1. What is the biggest challenge of mobile compu5ng? Jus5fy your answer with figures form state-­‐of-­‐the-­‐art. 2. Inves5gate actual mobile compu5ng applica5ons from google play hvps://play.google.com/store?hl=tr and list 3 of your favorite applica5ons with reasons. 40 QUESTIONS ? 41