정보통신공학개론 (2015년2학기)
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교과목명( 강의-실험-학점) : 정보통신공학개론(3-0-3)
담당교수: 조준호 ([email protected], 054-279-2377)
학수번호: EECE341
이수구분: 전공필수 - 개설학과: 전자
강의시간/강의실: 화,목 11:00~ 12:15 / LG연구동 104호
TA – 장태준([email protected], 054-279-8017)
 강의 목표
전자전기공학의 가장 중요한 분야중의 하나인 통신공학에 관한 기초적인
이론들과 그 응용방법을 포괄적으로 다룸으로써 학부수준에서 필수적인
지식을 제공한다.
Weight
1. Homework and Quiz
20 %
2. Midterm Exam (10/13
Tuesday, 11:00am-12:15pm,
at LG 104)
30 %
3. Final Exam (TBA,
11:00am-12:15pm, at LG
104)
40 %
4. Participation
10 %
5. Attendance
Pass/Fail
 강의 선수/수강 필수 사항
EECE233 신호 및 시스템
 성적 평가 계획
100%
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 강의 교재
A.B.Carlson, Communication systems, McGraw-Hill, 2010. (Fifth-Edition)
 강의 진도 계획
1 주 : What is Communication Engineering?, Fourier analysis
2 주 : Fourier series expansion
3 주 : Fourier transform
4 주 : Stochastic processes
5 주 : Double-Sideband(DSB) amplitude modulation
6 주 : Single-Sideband(SSB) & Vestigial-Sideband (VSB) amplitude
modulation
7 주 : AM demodulation, Demodulators
8 주 : Phase Modulation (PM), Frequency Modulation (FM)
9 주 : FM demodulation, Discriminators
10주 : Phase-Locked Loop (PLL)
11주 : Noise in communication systems
12주 : Spread spectrum communication
13주 : Sampling theory, Time-division multiplexing
14주 : Pulse-Code Modulation (PCM), Differential DPCM
15주 : Amplitude-Shift Keying(ASK),Phase-Shift Keying(PSK),
Frequency-shift Keying(FSK)
16주 : Matched filter
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o Communication : Information transfer
통신의 정의 ? Or 목적 ?
정보의 전달
o 통신 System 의 구성 요소 (5 elements)
Tx
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CH
Rx
Transmitter : Channel 특성에 맞도록 신호를 처리
Channel : 통신매체의 Noise,간섭, 과 왜곡 특성을 modeling.
Receiver : Transmitter 와 Channel 에 의해 변형된 신호를
복구한다.
 통신 System 의 분류 (4+2)
3
예)?
o 통신의 장애요소
• Distortion
• Interference
• Noise: 피할 수 없음
x0
x0
xi
xi
ex) 열잡음
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o 통신의 장애요소
• Distortion
• Interference
x0
x0
xi
• Noise: 피할 수 없음
xi
ex) 열잡음
o Noise (잡음) & Bandwidth
신호대 잡음 비
주파수 대역폭
C  W
정보전달 속도를 결정
P
log (1 
)[bits/sec]
N 0W
“ Fundamental Limitations ”
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 Fundamental Limitations
 Two constraints in designing communication system
Technological problems
Fundamental physical limitations
 (transmission) power
 (transmission) bandwidth
 (thermal) noise
 Channel capacity of a bandlimited white Gaussian noise
channel
C  W
P
log (1 
)[bits/sec]
N 0W
called the Hartley-Shannon law.
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 1.2 Modulation and Coding
 Modulating signal
 Carrier wave
 Modulation vs. demodulation
 Modem = modulator + demodulator
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 Sinusoidal carrier wave
Magnitude and phase
Amplitude and angle
Continuous-Wave (CW) modulation
 Amplitude Modulation (AM)
 Phase Modulation (PM)
 Frequency Modulation (FM)
Pulse modulation
 Pulse Amplitude Modulation (PAM)
 Quadrature Amplitude Modulation (QAM)
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 Why modulation?
 For efficient transmission
Power and antenna size
 To overcome hardware limitations
Filter design, DC leakage, etc.
 To reduce noise and interference
Wideband noise reduction
FM
Code-Division Multiple-Access (CDMA)
 For frequency assignment
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 For duplexing, multiplexing, and multiple-access
Duplexing
 Two-way communication
 FDD
 TDD
Multiplexing
 Cellular Downlink (DL)
 Frequency-Division Multiplexing (FDM), Orthogonal FDM
(OFDM)
 Time-Division Multiplexing (TDM)
 Code-Division Multiplexing (CDM)
Multiple Access
 Cellular Uplink (UL)
 FDMA, OFDMA
 TDMA
 CDMA
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 Coding Methods and Benefits
 Coding (EECE 577 Information and Coding Theory)
Source coding = Data compression
 Lossless
 Lossy
Channel coding = Data transmission
 Forward Error Correction (FEC)
 Automatic Repeat Request (ARQ)
 Source and Channel Codings
Source-channel separation theorem
 It holds in some important cases.
 In that case, source coding and channel coding can be
performed separately.
Joint source and channel coding
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 1.3 Electromagnetic Wave Propagation over Wireless Channels
 1897: Marconi patents a complete wireless telegraph system.
 Radio Frequency (RF) range of EM wave
 3kHz (VLF)
-300GHz (EHF)
 Light wave of EM wave
Infrared (IR)
Visible
Ultraviolet (UV)
 기를 이용한 통신
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 Wave propagation
Refraction: 굴절
Diffraction: 회절
Reflection: 반사
Scattering: 산란
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 Multipath phenomenon
Line-of-Sight (LOS/LoS) path
Non-LOS path: delayed version
 Attenuation
 Delay
 Specular vs. diffusive
 Multipath fading
Deterministic vs. Random Channel Model
 LTI vs. Linear Time-Varying Channel Models
 Wide-sense stationary uncorrelated scattering (WSSUS)
channel model
 Ground-wave propagation
LOS, reflection, refraction
Earth acts as a diffractor.
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 Sky-wave propagation
Troposphere: 대류권
Ionosphere: 전리층
Multi-hop paths
 Reflection: earth
 Refraction: ionosphere
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 1.4 Emerging Developments
 Circuit switching
dedicated line, traditional telephone comm.
 Packet switching
shared line
packets
Data transmission
 Cellular Telecommunications
1G
2G GSM
2.5G cdmaOne
3G WCDMA
4G LTE: OFDM
5G, B4G: massive MIMO, mmWave, etc.
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 FDMA, TDMA
 Ch. 7
 TDM
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 Code-Division Multiple-Access (CDMA: 부호분할 다중접속)
 Direct-sequence spread-spectrum modulation
 2.5G cdmaOne
 3G WCDMA
 Ch. 15
 Orthogonal Frequency-Division Multiplexing (OFDM)
 Parallel transmission on multiple overlapping but orthogonal
sub-carriers
 WiMax, WiBro
 Some Wi-Fi
 4G LTE
 Ch. 14
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 Wi-Fi, Bluetooth over Industrial, scientific, and medical (ISM)
bands
Commercial devices need to be authorized to be sold.
Use of such devices does not need authorization.
Limited power transmission is allowed for experimental
devices.
 Software Radio (SDR)
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Digital Communication System: Modulation, Demodulation, & Power Spectrum
Cellular Systems and Standards:
3G W-CDMA, 4G LTE
Prof. Joon Ho Cho
Department of Electrical Engineering, POSTECH
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 1.5 Social Impact and Historical Perspective
Welcome to the Exciting World of Information Age!
 Era of Information Revolution: 정보 혁명의 시대
 Era of Information Technology: 정보 기술의 시대
 Era of Information and Communication Technology (ICT): 정보
통신 기술의 시대
 Any time, any where, any one, any application…..
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Q. 인류의 역사를 1m 자에 늘어 놓으면?

David J. Smith, 지구의 역사가 1년이라면-지구와 인류의
역사를 알아가는 지식의 출발점
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Q. 인류 역사 속의 ‘시대’들
1.
2.
3.
4.
5.
구석기 시대
신석기 시대
청동기 시대
철기 시대
플라스틱 시대
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Q. 인류 역사 속의 ‘혁명’들?
1.
2.
3.
4.
5.
농업 혁명
상업 혁명
제 1차 산업 혁명
제 2차 산업 혁명: 전기, 화학
정보통신 혁명
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 Historical Develoepemts
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Q. 미래를 예측하는 가장 좋은 방법은?
 미래의 특징
 불확실하다
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