Introduction to Telecommunication Engineering
- 1. ECE 4371, Fall, 2017 Introduction to Telecommunication Introduction to Telecommunication Engineering Engineering Zhu Han Department of Electrical and Computer Engineering Class 1 Aug. 21st , 2017
- 2. ECE 4371 Outline Outline Instructor information Motivation to study communication systems 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 Background and Preview
- 3. ECE 4371 Instructor Information Instructor Information Office location: Engineering 2 W302 Office hours: Tue. 10am-2:00pm, Other time including weekend by appointment Email: zhan2@uh.edu or hanzhu22@gmail.com Phone: 713-743-4437(o), 301-996-2011(c) Course website: http://www2.egr.uh.edu/~zhan2/ECE4371/ECE4371_4117.html Research interests: Wireless Networking, Signal Processing, and Security http://wireless.egr.uh.edu/
- 4. ECE 4371 Motivations Motivations Recent Development – Satellite Communications – Telecommunication: Internet boom at the end of last decade – Wireless Communication: next boom? iPhone Job Market – Probably one of most easy and high paid majors recently – Intel changes to wireless, – Qualcom, Broadcom, TI, Marvell, Cypress Research Potential – One to one communication has less room to go, but multiuser communication is still an open issue. – Wimax, 3G, next generation WLAN
- 5. ECE 4371 Course Descriptions Course Descriptions What is the communication system? What are the major types? Analog or Digital Satellite, Fiber, Wireless… What are the theorems? What are the major components? 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?
- 6. ECE 4371 Textbook and Software Textbook and Software Require textbook: Modern Digital and Analog Communication Systems, Lathi and Ding Require Software: MATLAB http://www.mathworks.com/ or type helpwin in Matlab environment 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
- 7. ECE 4371 Homework, Project, and Exam Homework, Project, and Exam Homework 3-4 questions per week Projects: simple MATLAB programs Based on the simulation at the end of each chapter Exams Two independent exams plus final presentation/paper Votes for the percentages for homework, projects, and exams Participations Attendance and Feedback Quiz if the attendance is low
- 8. ECE 4371 Teaching Styles Teaching Styles Slides plus black board Slides can convey more information in an organized way Blackboard is better for equations and prevents you from not coming. 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 Presentation, Writing, English, …
- 9. ECE 4371 Other Policies 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
- 10. ECE 4371 Reasons to be my students 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 Free trips to conferences in Alaska, Hawaii, Europe, Asia… A kind of nice (at least looks like) Work with hope and happiness Graduate fast REU
- 11. ECE 4371 Chapter 1: Communication System Chapter 1: Communication System A B Engineering System Genetic System Social System History and fact of communication
- 12. ECE 4371 Communication System Components Communication System Components Source Coder Channel Coder Modulation + Source decoder Channel decoder demodulation Distortion and noise transmitter channel receiver Source input Reconstructed Signal output D/A A/D
- 13. ECE 4371 Communication Process Communication Process Message Signal Symbol Encoding Transmission Decoding Re-creation Broadcast Point to Point
- 14. ECE 4371 Telecommunication Telecommunication Telegraph Fixed line telephone Cable Wired networks Internet Fiber communications Communication bus inside computers to communicate between CPU and memory
- 15. ECE 4371 Wireless Communications Wireless Communications Satellite TV Cordless phone Cellular phone Wireless LAN, WIFI Wireless MAN, WIMAX Bluetooth Ultra Wide Band Wireless Laser Microwave GPS Ad hoc/Sensor Networks
- 16. ECE 4371 Analog or Digital Analog or Digital Common Misunderstanding: Any transmitted signals are ANALOG. NO DIGITAL SIGNAL CAN BE TRANSMITTED Analog Message: continuous in amplitude and over time – AM, FM for voice sound – Traditional TV for analog video – First generation cellular phone (analog mode) – Record player Digital message: 0 or 1, or discrete value – VCD, DVD – 2G/3G cellular phone – Data on your disk – Your grade Digital age: why digital communication will prevail
- 17. ECE 4371 ADC/DAC ADC/DAC Analog-to-Digital Conversion (ADC) and Digital-to-Analog Conversion (DAC) are the processes that allow digital computers to interact with these everyday signals. Digital information is different from its continuous counterpart in two important respects: it is sampled, and it is quantized
- 18. ECE 4371 Source Coder Source Coder Examples – Digital camera: encoder; TV/computer: decoder – Camcorder – Phone – Read the book Theorem – How much information is measured by Entropy – More randomness, high entropy and more information
- 19. ECE 4371 Channel, Bandwidth, Spectrum Channel, Bandwidth, Spectrum Bandwidth: the number of bits per second is proportional to B http://www.ntia.doc.gov/osmhome/allochrt.pdf
- 20. ECE 4371 Power, Channel, Noise Power, Channel, Noise Transmit power – Constrained by device, battery, health issue, etc. Channel responses to different frequency and different time – Satellite: almost flat over frequency, change slightly over time – Cable or line: response very different over frequency, change slightly over time. – Fiber: perfect – Wireless: worst. Multipath reflection causes fluctuation in frequency response. Doppler shift causes fluctuation over time Noise and interference – AWGN: Additive White Gaussian noise – Interferences: power line, microwave, other users (CDMA phone)
- 21. ECE 4371 Shannon Capacity Shannon Capacity Shannon Theory – It establishes that given a noisy channel with information capacity C and information transmitted at a rate R, then if R<C, there exists a coding technique which allows the probability of error at the receiver to be made arbitrarily small. This means that theoretically, it is possible to transmit information without error up to a limit, C. – The converse is also important. If R>C, the probability of error at the receiver increases without bound as the rate is increased. So no useful information can be transmitted beyond the channel capacity. The theorem does not address the rare situation in which rate and capacity are equal. Shannon Capacity s bit SNR B C / ) 1 ( log2
- 22. ECE 4371 Modulation Modulation Process of varying a carrier signal in order to use that signal to convey information – Carrier signal can transmit far away, but information cannot – Modem: amplitude, phase, and frequency – Analog: AM, amplitude, FM, frequency, Vestigial sideband modulation, TV – Digital: mapping digital information to different constellation: Frequency-shift key (FSK)
- 23. ECE 4371 Example Example Figure 1.6 page 12 Modulation over carrier fc s(t)=Accos(2fct) for symbol 1; -Accos(2fct) for symbol 0 Transmission from channel x(t)=s(t)+w(t) Correlator Decoding – If the correlator output yT is greater than 0, the receiver output symbol 1; otherwise it outputs symbol 0. 0 , 5 . 0 1 , 5 . 0 ) 2 cos( ) ( 0 symbol for w A symbol for w A dt t f t x y T c T c T c T
- 24. ECE 4371 Channel Coding Channel Coding Purpose – Deliberately add redundancy to the transmitted information, so that if the error occurs, the receiver can either detect or correct it. Source-channel separation theorem – If the delay is not an issue, the source coder and channel coder can be designed separately, i.e. the source coder tries to pack the information as hard as possible and the channel coder tries to protect the packet information. Popular coder – Linear block code – Cyclic codes (CRC) – Convolutional code (Viterbi, Qualcom) – LDPC codes, Turbo code, 0.1 dB to Channel Capacity
- 25. ECE 4371 Quality of a Link (service, QoS) Quality of a Link (service, QoS) Mean Square Error Signal to noise ratio (SNR) – Bit error rate – Frame error rate – Packet drop rate – Peak SNR (PSNR) – SINR/SNIR: signal to noise plus interference ratio Human factor N i i i X X N MSE 1 2 | ˆ | 1 2 2 G P P tx rec
- 26. ECE 4371 Multiplexing Multiplexing Space-division multiplexing Frequency-division multiplexing Time-division multiplexing Code-division multiplexing
- 27. ECE 4371 Communication Networks Communication Networks Connection of 2 or more distinct (possibly dissimilar) networks. Requires some kind of network device to facilitate the connection. Internet Net A Net B
- 28. ECE 4371 Broadband Communication Broadband Communication
- 29. ECE 4371 OSI Model OSI Model Open Systems Interconnections; Course offered next semester
- 30. ECE 4371 TCP/IP Architecture TCP/IP Architecture • TCP/IP is the de facto global data communications standard. • It has a lean 3-layer protocol stack that can be mapped to five of the seven in the OSI model. • TCP/IP can be used with any type of network, even different types of networks within a single session.
- 31. ECE 4371 History of Telecommunication History of Telecommunication Table 1.1 page 17 – 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
- 32. ECE 4371 History of Telecommunication 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
- 33. ECE 4371 Summary Summary Course Descriptions Chapter 1: Communication System Structure – Basic Block Diagram – Typical Communication systems – Analog or Digital – Entropy to Measure the Quantity of Information – Channels – Shannon Capacity – Spectrum Allocation – Modulation – Communication Networks Question on Chapter 2: Signals and signal space