1 정보통신공학개론 (2015 년 2 학기 ) 교과목명 ( 강의 - 실험 - 학점 ) :...
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정보통신공학개론 (2015 년 2 학기 )
• 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 / LG 연구동 104 호• 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 .
강의 선수 /수강 필수 사항 EECE233 신호 및 시스템
성적 평가 계획
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
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 10 주 : Phase-Locked Loop (PLL) 11 주 : Noise in communication systems 12 주 : Spread spectrum communication 13 주 : Sampling theory, Time-division multiplexing 14 주 : Pulse-Code Modulation (PCM), Differential DPCM 15 주 : Amplitude-Shift Keying(ASK),Phase-Shift Keying(PSK), Frequency-shift Keying(FSK) 16 주 : Matched filter
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o Communication : Information transfer
통신의 정의 ? Or 목적 ?
정보의 전달
o 통신 System 의 구성 요소 (5 elements)
• Transmitter : Channel 특성에 맞도록 신호를 처리• Channel : 통신매체의 Noise, 간섭 , 과 왜곡 특성을 modeling. 예 )?
• Receiver : Transmitter 와 Channel 에 의해 변형된 신호를 복구한다 .
통신 System 의 분류 (4+2)
Tx CH Rx
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o 통신의 장애요소• Distortion • Interference
• Noise: 피할 수 없음 ex) 열잡음
0x 0x
ix ix
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o 통신의 장애요소• Distortion • Interference
• Noise: 피할 수 없음 ex) 열잡음
o Noise ( 잡음 ) & Bandwidth
신호대 잡음 비 정보전달 속도를 결정 주파수 대역폭
“ Fundamental Limitations ”
0x 0x
ix ix
sec]/)[1(log0
bitsWNP
WC
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Fundamental Limitations Two constraints in designing communication system
Technological problemsFundamental physical limitations
(transmission) power(transmission) bandwidth(thermal) noise
Channel capacity of a bandlimited white Gaussian noise channel
called the Hartley-Shannon law.
sec]/)[1(log0
bitsWNP
WC
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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 waveMagnitude and phaseAmplitude and angleContinuous-Wave (CW) modulation
Amplitude Modulation (AM)Phase Modulation (PM)Frequency Modulation (FM)
Pulse modulationPulse 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 reductionFM Code-Division Multiple-Access (CDMA)
For frequency assignment
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For duplexing, multiplexing, and multiple-accessDuplexing
Two-way communicationFDDTDD
MultiplexingCellular Downlink (DL)Frequency-Division Multiplexing (FDM), Orthogonal FDM
(OFDM)Time-Division Multiplexing (TDM)Code-Division Multiplexing (CDM)
Multiple AccessCellular Uplink (UL) FDMA, OFDMATDMACDMA
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Coding Methods and Benefits Coding (EECE 577 Information and Coding Theory)
Source coding = Data compressionLosslessLossy
Channel coding = Data transmissionForward Error Correction (FEC)Automatic Repeat Request (ARQ)
Source and Channel CodingsSource-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 waveInfrared (IR)VisibleUltraviolet (UV)
기를 이용한 통신
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Wave propagation Refraction: 굴절Diffraction: 회절Reflection: 반사
Scattering: 산란
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Multipath phenomenonLine-of-Sight (LOS/LoS) pathNon-LOS path: delayed version
AttenuationDelay
Specular vs. diffusive Multipath fading
Deterministic vs. Random Channel ModelLTI vs. Linear Time-Varying Channel ModelsWide-sense stationary uncorrelated scattering (WSSUS)
channel model Ground-wave propagation
LOS, reflection, refractionEarth acts as a diffractor.
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Sky-wave propagationTroposphere: 대류권 Ionosphere: 전리층Multi-hop paths
Reflection: earth Refraction: ionosphere
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1.4 Emerging Developments Circuit switching
dedicated line, traditional telephone comm. Packet switching
shared linepacketsData transmission
Cellular Telecommunications1G 2G GSM2.5G cdmaOne3G WCDMA4G 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) bandsCommercial 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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Cellular Systems and Standards:3G W-CDMA, 4G LTE
Prof. Joon Ho Cho
Department of Electrical Engineering, POSTECH
Digital Communication System: Modulation, Demodulation, & Power Spectrum
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1.5 Social Impact and Historical Perspective
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…..
Welcome to the Exciting World of Information Age!
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Q. 인류의 역사를 1m 자에 늘어 놓으면 ?
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David J. Smith, 지구의 역사가 1 년이라면 - 지구와 인류의 역사를 알아가는 지식의 출발점
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Q. 인류 역사 속의 ‘ 시대’ 들
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1. 구석기 시대2. 신석기 시대3. 청동기 시대4. 철기 시대5. 플라스틱 시대
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Q. 인류 역사 속의 ‘ 혁명’ 들 ?
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1. 농업 혁명2. 상업 혁명3. 제 1 차 산업 혁명4. 제 2 차 산업 혁명 : 전기 , 화학 5. 정보통신 혁명
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Historical Develoepemts
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Q. 미래를 예측하는 가장 좋은 방법은 ?
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미래의 특징 불확실하다