ENGG 2310-B Principles of Communication Systems

Transcription

1 ENGG 2310-B Principles of Communication Systems Introduction and Course Overview Prof. Wing-Kin Ma Department of Electronic Engineering September 3, 2018 Most of the pictures were taken from the internet. ENGG 2310-B Term

2 What is Communication? Communication refers to the process of transmitting information from one point to another. ENGG 2310-B Term

3 5G 5G refers to the fifth generation mobile networks. It is under development, and is expected to launch by 2020 See ENGG 2310-B Term

4 Question: How do we communicate? Through what media, and by what means? ENGG 2310-B Term

5 Example: Telephone (Fixed Line) ENGG 2310-B Term

6 Alexander Graham Bell ( ) Bell at the opening of the long-distance line from New York to Chicago in ENGG 2310-B Term

7 Example: Radio and TV Broadcast ENGG 2310-B Term

8 Guglielmo Marconi ( ) ENGG 2310-B Term

9 Edwin H. Armstrong ( ) ENGG 2310-B Term

10 Example: Mobile Networks (a.k.a. Cellular Networks) 1G phone ENGG 2310-B Term iphone, supporting 4G LTE

11 More Communication Examples Local area network, computer communication Satellite communication Underwater communication Optical communication Li-Fi, i.e., visible light communication Powerline communication Talking in ENGG 2310-B Class (please keep quiet in class, unless you are raising questions to teachers or tutors) ENGG 2310-B Term

12 Communication Systems Can be Complex ENGG 2310-B Term

13 ENGG 2310-B Term

14 A Simplified View on Communication Systems Information Source Network and Control layers Transmitter Receiver Network and Control layers Information Sink Channel ENGG 2310-B Term

15 A Simplified View on Communication Systems Information Source Network and Control layers Transmitter Receiver Network and Control layers Information Sink Channel Information: can take digital form, or analog form examples: voice, music, data files, pictures, video ENGG 2310-B Term

16 A Simplified View on Communication Systems Information Source Network and Control layers Transmitter Receiver Network and Control layers Information Sink Channel Channel: The physical medium for transmission examples: copper wires, optical fibers, free space. ENGG 2310-B Term

17 A Simplified View on Communication Systems Information Source Network and Control layers Transmitter Receiver Network and Control layers Information Sink Channel Transmitter : transmitter converts info. to a form suitable for transmission over the channel. example: frequency modulation (FM) in radio broadcast. ENGG 2310-B Term

18 A Simplified View on Communication Systems Information Source Network and Control layers Transmitter Receiver Network and Control layers Information Sink Channel Receiver : receiver converts the signal transmitted over the channel back to info. receiver also plays the role of combating undesirable or non-ideal effects incurred by the channel. ENGG 2310-B Term

19 Open System Interconnect (OSI) Model Application Application Presentation Presentation Session Peer Protocols Session Transport Transport Network Network Link Link Physical Physical Physical Medium A layered model introduced in computer communications; not important for us to know the details with every layer. The transmitter, channel and receiver lies in the physical layer this will be our focus. ENGG 2310-B Term

20 Question: What is the main resource for communication, for example, in wireless? ENGG 2310-B Term

21 Challenges We always want to transmit or receive more, and have it faster. We have limited resources. In wireless communication, the resources are available radio frequency (RF) bands. They are very limited! ENGG 2310-B Term

22 Electromagnetic Spectrum Different frequencies are like different tones. ENGG 2310-B Term

23 Radio Spectrum ENGG 2310-B Term

24 Spectrum Allocation in the US (it s full, simply put) ENGG 2310-B Term

25 Mobile Spectrum is very Expensive Here are some facts according to a newspaper article in a total of 49.2 megahertz of paired radio spectrum in the 1.9GHz to 2.2GHz band was auctioned off. the spectrum prices (of mobile) are fairly close to the reserve price of HK$48 million per megahertz SmarTone bought a total of 19.8MHz of radio spectrum for HK$980.4 million China Mobile Hong Kong would pay HK$970.4 million for 19.6MHz of spectrum Hutchison Telecom won 9.8MHz of spectrum for HK$470.4 million. ENGG 2310-B Term

26 Current Trend with Mobile Data Service It is estimated that wireless traffic is now doubling or tripling annually. ENGG 2310-B Term

27 Question: Given the same resource, how can we communicate faster? ENGG 2310-B Term

28 Example: Wired Internet Connections at Home In the 1990 s, the data rate is about 56k bits per second (bps). Now, we are talking about hundreds of Mbps, or more. The channel remains the same copper wires. What makes the difference? Better transmitter-receiver technology (and smart people who invented new tech). ENGG 2310-B Term

29 How Fast Can it Be? Note that 1kbps sending 1 bit every 1ms = 0.001s 1Mbps sending 1 bit every 1µs= s 1Gbps sending 1 bit every 1ns= s Signal processing, RF and circuits tech. play central roles. ENGG 2310-B Term Software defined radio.

30 Example: Mobile Evolution ENGG 2310-B Term

31 Example: Mobile Evolution Key for 5G evolution: millimeter-wave communications, small cells, multi-input-multi-output (MIMO) in massive scales See ENGG 2310-B Term

32 Objective of this Course To provide you with key and foundational concepts on communication systems (both classical and frontier). ENGG 2310-B Term

33 Topics to Be Covered Communication systems overview A review on basic concepts of Signals and Systems, particularly, Fourier transform Modulation techniques amplitude modulation angle and frequency modulation Digital representation of analog signals Digital transmission techniques baseband transmission bandpass transmission ENGG 2310-B Term

34 Instructor: Me you see here General Information Teaching Assistants: Wai Yiu Keung, Yatao Liu, Yuening Li Lecture Hours and Venues: Mon 1:30-3:15pm, Y.C. Liang Hall 104 Tue 2:30-3:15pm, Lady Shaw Building LT4 Course Website: Please check regularly ENGG2310-B: ENGG 2310-B Term

35 Assessment for ENGG2310-B In-Class Quizzes (7%): A number of quizzes will be carried out during class. The times of the quizzes are random. Assignments and Labs (23%): Lab arrangements will be announced later. For assignments, submit to SHB 329. The rule for late submission: score received = original score 0.85 number of days late. No assignment will be accepted after the solution is distributed. Midterm Exam (20%): In-class. Tentative date: Oct 22 in class. Final Exam (50%) ENGG 2310-B Term

36 Other Things No tutorial for the first week, as usual Your scores can be checked in the Blackboard CUHK. Any issue must be raised within one week from the announcement of the scores. Check CUHK-link ! This is the only way we can find you! ENGG 2310-B Term

37 Learning Resources Handouts, as well as supplementary materials, are provided; please check the course website regularly. Read Handout 2, Fourier transform, for preparation of the Sep 4 class. There are many textbooks for communications, which you can easily find in the university library. Recommended textbooks: Simon Haykin and Michael Moher, Communication Systems (5th Edition), Wily & Sons Ltd. B. P. Lathi and Z. Ding, Modern Digital and Analog Communication Systems (4th Edition), Oxford University Press. ENGG 2310-B Term

38 Academic Honesty CUHK has clear definitions and guidelines on academic honesty; for the details We adopt a policy of zero tolerance on plagiarism, simply stated. Disciplinary actions, usually involving severe penalties, will be taken for detected plagiarism cases. Simply put, don t copy, don t buy solution, just honestly do your work, and credit others contribution. ENGG 2310-B Term

39 Student/Faculty Expectations on Teaching & Learning The Faculty has clearly established a set of expectations for the students and faculty members of our Faculty With a view to building up an atmosphere of mutual respect, acknowledgement, and responsibility between our students and faculty members as well as to enhancing teaching and learning in the Faculty. Student/Faculty Expectations on Teaching and Learning, Faculty of Engineering, CUHK, 29 August 2011, ENGG 2310-B Term