정보통신공학개론 (2015 년 2 학기 ) 교과목명 ( 강의 - 실험 - 학점 ) : 정보통신공학개론 (3-0-3)

1. 정보통신공학개론 (2015년2학기) • 교과목명( 강의-실험-학점): 정보통신공학개론(3-0-3) • 담당교수:조준호 (jcho@postech.ac.kr, 054-279-2377) • 학수번호: EECE341 • 이수구분: 전공필수 - 개설학과:전자 • 강의시간/강의실: 화,목 11:00~ 12:15 / LG연구동 104호 • TA – 장태준(taejun8@postech.ac.kr, 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

2. 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

3. Communication : Information transfer 통신의 정의 ? Or목적 ? 정보의 전달 • 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) CH Rx Tx

4. 통신의 장애요소 • Distortion • Interference • Noise: 피할 수 없음 ex) 열잡음

5. 통신의 장애요소 • Distortion • Interference • Noise: 피할 수 없음 ex) 열잡음 • Noise (잡음) & Bandwidth 신호대 잡음 비 정보전달 속도를 결정 주파수 대역폭 “ Fundamental Limitations ”

6. 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 called the Hartley-Shannon law.

7. 1.2 Modulation and Coding • Modulating signal • Carrier wave • Modulation vs. demodulation • Modem = modulator + demodulator

8. 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)

9. 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

11. 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

12. 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

13. 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

14. Wave propagation • Refraction: 굴절 • Diffraction: 회절 • Reflection: 반사 • Scattering: 산란

15. 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.

16. Sky-wave propagation • Troposphere: 대류권 • Ionosphere: 전리층 • Multi-hop paths • Reflection: earth • Refraction: ionosphere

17. 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.

18. FDMA, TDMA • Ch. 7 • TDM

20. Code-Division Multiple-Access (CDMA: 부호분할다중접속) • 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

21. 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)

22. Cellular Systems and Standards:3G W-CDMA, 4G LTE Digital Communication System: Modulation, Demodulation, & Power Spectrum Prof. Joon Ho Cho Department of Electrical Engineering, POSTECH

33. 1.5 Social Impact and Historical Perspective • Era of Information Revolution: 정보혁명의 시대 • Era of Information Technology: 정보기술의 시대 • Era of Information and Communication Technology (ICT): 정보통신 기술의 시대 • Any time, any where, any one, any application….. Welcome to the Exciting World of Information Age!

34. Q. 인류의역사를 1m 자에늘어 놓으면? • David J. Smith, 지구의 역사가 1년이라면-지구와 인류의 역사를 알아가는 지식의 출발점

35. Q. 인류 역사 속의 ‘시대’들 구석기 시대 신석기 시대 청동기 시대 철기 시대 플라스틱 시대

36. Q. 인류 역사 속의 ‘혁명’들? 농업 혁명 상업 혁명 제 1차 산업 혁명 제 2차 산업 혁명: 전기, 화학 정보통신 혁명

37. Historical Develoepemts

39. Q. 미래를 예측하는 가장 좋은 방법은? • 미래의 특징 • 불확실하다