ENGG 2310-B | Term 1 | 2018-19

1

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 Principles of Communication Systems

ENGG 2310-B | Term 1 | 2018-19

2

What is Communication?

• Communication refers to the process of transmitting information from one point to another.

ENGG 2310-B | Term 1 | 2018-19

3

5G

• 5G refers to the fifth generation mobile networks. • It is under development, and is expected to launch by 2020

• See https://www.youtube.com/watch?v=pbvkFwMN_PY

ENGG 2310-B | Term 1 | 2018-19

4

Question:

How do we communicate? Through what media, and by what means?

ENGG 2310-B | Term 1 | 2018-19

5

Example: Telephone (Fixed Line)

ENGG 2310-B | Term 1 | 2018-19

6

Alexander Graham Bell (1847-1922)

Bell at the opening of the long-distance line from New York to Chicago in 1892.

ENGG 2310-B | Term 1 | 2018-19

7

Example: Radio and TV Broadcast

ENGG 2310-B | Term 1 | 2018-19

8

Guglielmo Marconi (1874-1937)

ENGG 2310-B | Term 1 | 2018-19

9

Edwin H. Armstrong (1890-1954)

ENGG 2310-B | Term 1 | 2018-19

10

Example: Mobile Networks (a.k.a. Cellular Networks)

1G phone

iphone, supporting 4G LTE

ENGG 2310-B | Term 1 | 2018-19

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 1 | 2018-19

12

Communication Systems Can be Complex

ENGG 2310-B | Term 1 | 2018-19

13

ENGG 2310-B | Term 1 | 2018-19

14

A Simplified View on Communication Systems

InformationSource

Transmitter

Channel

Receiver InformationSink

Network andControl layers

Network andControl layers

ENGG 2310-B | Term 1 | 2018-19

15

A Simplified View on Communication Systems

• Information: − can take digital form, or analog form − examples: voice, music, data files, pictures, video…

InformationSource

Transmitter

Channel

Receiver InformationSink

Network andControl layers

Network andControl layers

ENGG 2310-B | Term 1 | 2018-19

16

A Simplified View on Communication Systems

• Channel: − The physical medium for transmission − examples: copper wires, optical fibers, free space.

InformationSource

Transmitter

Channel

Receiver InformationSink

Network andControl layers

Network andControl layers

ENGG 2310-B | Term 1 | 2018-19

17

A Simplified View on Communication Systems

• Transmitter : − transmitter converts info. to a form suitable for

transmission over the channel. − example: frequency modulation (FM) in radio broadcast.

InformationSource

Transmitter

Channel

Receiver InformationSink

Network andControl layers

Network andControl layers

ENGG 2310-B | Term 1 | 2018-19

18

A Simplified View on Communication Systems

• 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.

InformationSource

Transmitter

Channel

Receiver InformationSink

Network andControl layers

Network andControl layers

ENGG 2310-B | Term 1 | 2018-19

19

Open System Interconnect (OSI) Model

• 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.

Application

Presentation

Session

Transport

Network

Link

Physical

Application

Presentation

Session

Transport

Network

Link

Physical

Physical

Medium

Peer Protocols

ENGG 2310-B | Term 1 | 2018-19

20

Question:

What is the main resource for communication, for example, in wireless?

ENGG 2310-B | Term 1 | 2018-19

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 1 | 2018-19

22

Electromagnetic Spectrum

• Different frequencies are like different tones.

ENGG 2310-B | Term 1 | 2018-19

23

Radio Spectrum

ENGG 2310-B | Term 1 | 2018-19

24

Spectrum Allocation in the US (it’s full, simply put)

ENGG 2310-B | Term 1 | 2018-19

25

Mobile Spectrum is very Expensive

• Here are some facts according to a newspaper article in 2014 ‒ http://www.scmp.com/business/companies/article/1658267/smartone-and-

china-mobile-biggest-spenders-3g-spectrum-auction

• 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 1 | 2018-19

26

Current Trend with Mobile Data Service

• It is estimated that wireless traffic is now doubling or tripling

annually.

ENGG 2310-B | Term 1 | 2018-19

27

Question:

Given the same resource, how can we communicate faster?

ENGG 2310-B | Term 1 | 2018-19

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 1 | 2018-19

29

How Fast Can it Be?

• Note that 1kbps sending 1 bit every 1ms = 0.001s 1Mbps sending 1 bit every 1µs= 0.000001s 1Gbps sending 1 bit every 1ns= 0.000000001s

• Signal processing, RF and circuits tech. play central roles.

Software defined radio.

ENGG 2310-B | Term 1 | 2018-19

30

Example: Mobile Evolution

ENGG 2310-B | Term 1 | 2018-19

31

Example: Mobile Evolution

• Key for 5G evolution: millimeter-wave communications, small cells,

multi-input-multi-output (MIMO) in massive scales • See https://www.youtube.com/watch?v=GEx_d0SjvS0

ENGG 2310-B | Term 1 | 2018-19

32

Objective of this Course

• To provide you with key and foundational concepts on communication systems (both classical and frontier).

ENGG 2310-B | Term 1 | 2018-19

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 1 | 2018-19

34

General Information

• Instructor: Me you see here

• 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: http://www.ee.cuhk.edu.hk/~wkma/engg2310/

ENGG 2310-B | Term 1 | 2018-19

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 ×0.85number 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 1 | 2018-19

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 email! This is the only way we can find you!

ENGG 2310-B | Term 1 | 2018-19

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 1 | 2018-19

38

Academic Honesty

CUHK has clear definitions and guidelines on academic honesty; for the details

• http://www.cuhk.edu.hk/policy/academichonesty/

• 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 1 | 2018-19

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, http://www.erg.cuhk.edu.hk/erg-intra/upload/documents/StaffStudentExpectations.pdf