Wireless Networking:

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Wireless Networking:

Fundamentals and Applications

PROF. MICHAEL TSAI 2016 SPRING

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Before we start:

Filtering mechanism

• New: No registration in the primary enrollment

• You will need to obtain a registration code to enroll

• We only have limited sets of hardware for projects

• Question: how do we determine who can get in?

• Solution: a filtering mechanism

 I will tell you at the end

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Before we start:

Warnings

• 4th time to teach the course

• Be prepared to time-consuming lab assignments (10+, 20+, or 30+ hours per assignment!)

Expect lots of hands-on time.

• Will do my best to prepare the lectures,

but don’t know if they will be easy to absorb

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Course Objective

• Learn about wireless communications and networks

• Why is it so different from wired communications and networks?

• Wireless communications = lots of random errors, less reliable

• Not so complicated, even a CS student can understand it. 

• See the course outline on the course website …

• And the next page

(課程大綱在下面幾頁…我

有在課程一開始的時候說喔 ~~~)

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Fundamentals

• Basics of wireless communications

• Radio propagation (below physical layer)

• Modulation (physical layer)

• Spread spectrum (physical layer)

• Diversity (physical layer)

• Media Access Control (MAC) protocol for Wireless

• Routing in Wireless Networks

• Transport Layer over Wireless Not so fundamental:

• Advanced topics in research papers

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Applications

• Visible Light Communications (VLC)

• Vehicular Networks (called VANET sometimes)

• WiFi (Wireless LAN, WLAN)

• Wireless Sensor Networks

• Acoustic Near Field Communications (maybe)

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Hands-on Experience

• 4 lab assignments

• Completed by teams of 5 (12 teams)

• Goal:

• Learn from your own experience (1^st hand)

• Not from the lectures/the books (2^nd hand)

• Fun!

• Cons: need to spend lots of time (20+ hrs per assignment, on average)

• Final project of your own choice, related to our course

(cannot be related to your research – 大學專題, 碩論, etc.)

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Prerequisite

• I would like to say….NONE,

• but the truth is…

• Just a few ones on the list:

• You know the C programming language

• Good at using Google to look for answers (not kidding, very important)

• Some basic knowledge about probability & calculus (basic is the key word, and we will cover some)

• You are really interested in wireless communications & networks

• Optional, but good to have:

• You have taken “Computer Networks”

• You have taken “Data structure” and/or “Algorithm”

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Course grade

Items Weight

Project assignments:

project 1 15%

project 2 15%

project 3 15%

project 4 15%

Final project 30%

Per class quiz (class participation) 10%

• No exams! But quizzes every week (don’t know when)

• Mapping from 100% score to the letter grade determined later

• Since this is not a required course, the general idea is that we

will be generous given that you completed all assignments. 9

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References

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Chandra, Dobkin, Bensky, Lexa, Lide, and Dowla, “Wireless Networking – know it all,”

Newnes, 2007

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References

Andrea Goldsmith, Wireless Communications, Cambridge University Press, 2005

Theodore S. Rappaport, Wireless Communications:

Principles and Practice, 2^ndEdition, 2002

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The teaching team

Teaching Assistants

蔡欣穆 (Michael)

Direct your questions to:

12 E-mail: wn@csie.ntu.edu.tw Facebook group:

https://www.facebook.com/groups/wn15spring/

TA Office Hour : Tue. 1320 – 1410 / TBA

林靜茹 (Kate)

中研院資創中心魏佑霖陳勁宇

陳艾苓詹宗霖

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Zero-tolerance policy (Plagiarism)

• We will NOT tolerate any PLAGIARISM (Quiz/Lab/Homework).

• Students who gets caught will get an F , no second chance.

(+ possible university disciplinary actions)

• The TA’s will look for

• (1) signs of copied codes in your project assignment source codes

• (2) signs that content in your final project is found somewhere else

**• *For handwritten homework, please indicate references for each problem**

• Books or Internet URL or a person.

• If none, then indicate “none”.

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Zero-tolerance policy (assignment deadline)

• Homework deadline is HARD deadline.

• You get

0

point for the homework after the submission deadline

• You get

0

point for the lab if you don’t demo on time/submit the source code to the repository

• However, we will still grade it for you, if you choose to submit it (after the deadline)

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My teaching style

• Interactions in the class

• Please please please please ask me questions

• (Or I will ask you questions…)

• No question is dumb question

• (Since lots of you have very little background knowledge)

• Class material is easy to understand

• Some handwritten materials, prepare to take note

• But project assignments require lots of efforts

• English slides but taught in Mandarin Chinese

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Misc. Information

• Class time: Friday 09:10-12:10,

• Will take a break when more than 30% of students is about to fall into sleep

• Classroom: CSIE R102

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Lab1 CamCom

Build up your own VLC system!

Tx: Zigduino board × LED Rx: Camera Sensor

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Lab2 USRP

• What is USRP?

• Used for software-defined radio experiment

• For example, Multi-Input Multi-Output(MIMO) experiment

• Lab requirement

• Tx / Rx Radio communication

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Lab2 USRP

• Lab metrics

• Tx / Rx Sync

• Channel estimation

• Phase correction

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Lab3 Introduction-JJY Simulator

• What is JJY?

• the call sign of a longwave time signal radio station

• What is the purpose of using JJY?

• Used to synchronize consumer radio-controlled clocks throughout Japan with Japan Standard Time(JST)

• In Japan, the station broadcasts the JJY signal from two sites

• The Mount Otakadoya : 40 kHz signal

• The Mount Hagane : 60 kHz signal

• Official website

• http://jjy.nict.go.jp/index-e

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• What is the purpose of lab2?

• Simulating time signal by Zigduino

• Synchronizing radio-controlled clocks with radio signal (time signal)

• Time signal standard

• JJY time code  encoded JST(Japan Standard Time)

• WWVB time code  encoded UTC(Universal Time Coordinated)

• …

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Lab4 - Project Scheme

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Lab4 - Device Map (CSIE 4F)

DST

SRC

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特別評分機制

• 90% Lab 團體成績 (由各個作業負責的助教決定)

• 10% 小組互評成績

• 匿名

• 給分範圍為 -2.5 ~ 2.5

• 給分總和需等於 0 (ex 0.25/0.25/-0.25/-0.25)

• 目的

• Report 上的工作分配有時無法準確的表達各個組員各自的想法，

因此添加此機制作參考

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• 情境 1 : 大家都認為彼此付出一樣心力

• 大家彼此都給 0 分，此組員成績 = Lab 團體成績

• 情境 2 : 1 個 Free Rider

• 大家都給 -2.5，共得 -10，此人成績 = Lab 團體成績 – 10

• 大家都給救火者 2.5，共得 10，此人成績 = Lab 團體成績 + 10

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• 假設 A 組全組認真參與；B 組存在 Free Rider(s)

• A 組在此機制下最高得分只有 90 %，然而 B 組最高分數卻較高 90% + 10%，是否不公平？

• A 組最高分確實只有 90 %，然而學期末總成績將依據常態分佈

給分，所以總分高低不是重點

• 課程安排上作業傾向需要五人團隊合作，理論上 B 組的 Lab 表

現會較 A 組差，因而得到較低的Lab 團體成績，即使加上互評

成績不見得會拿到較 A 組高的分數

• 假若 B 組救火者有能力將 Lab 表現得與 A 組相當甚至更佳，那

麼最後因為最高分數較高而得到較 A 組佳的成績是實至名歸

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Filtering

• 五個project必須以同一組人力完成

• 組中有中途退選的, 必須以該組剩下人力完成, 不再調整分組.

• 3/1(二) 23:59 前找好組員，並完成 2016 WNFA 小組登記表的 Google 表單填寫 https://goo.gl/Zrl2Cl

• 系級

• 學號

• 姓名

• 排序:

• 1. 計算整組積分

• 大四 / 碩二 +1

• 大二 / 大一 -1

• 資訊學群科系 +1

• 電機資訊學院外科系所 -1

• 2. 排序完畢以後取前12組

• 3. 積分平手的, 以填寫Google表單的時間作排序

• 4. 名單將於下週四 23:59 以前公布，授權碼也會在屆時email發放。

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