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http://eent3.lsbu.ac.uk/staff/baoyb/dctc. Data Communication Theory & Coding. Website: http :// eent3.lsbu.ac.uk/staff/baoyb/dctc http://www.lsbu.ac.uk/bb/. Methods of Teaching and Learning : Lectures, Tutorials and Workshops.
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http://eent3.lsbu.ac.uk/staff/baoyb/dctc Data Communication Theory & Coding Ya Bao
Website:http://eent3.lsbu.ac.uk/staff/baoyb/dctc http://www.lsbu.ac.uk/bb/ Methods of Teaching and Learning : Lectures, Tutorials and Workshops Assessment of the Module:2-hour written examination -- 70% Laboratory report -- 30% Lecturer: Ya Bao and J G Zhang Lab tutor: Ya Bao and Vincent Siyau. Ya Bao
Text Books Ya Bao
Chapter 1. Introduction Ya Bao
1.1 Historical Background table_01_01a table_01_01a Ya Bao
1.3 Channel Characteristics • Types of transmission channels • Electromagnetic wave propagation channels (wireless) • Guided electromagnetic wave channels (wired) • Optical links Ya Bao
1.4 System analysis techniques Time-domain and frequency-domain analyses Signal frequency and signal bandwidth, Fourier Analysis Modulation and communication theories Changing some parameter of a carrier wave in accordance with the message signal. Detection theory Probability theory Ya Bao
1.5 The Electromagnetic Spectrum • Electromagnetic Waves and Energy • Velocity:speed at which the energy travels through • Frequency: the number of oscillations or cycles per second (hertz, abbreviated Hz) of the waveform • Wavelength: the distance between peaks of the oscillations of the energy wave Ya Bao
Wavelength can also be measured as the distance between the negative peaks, zero points. Ya Bao
speed of light: • The propagation velocity is less in any medium other than vacuum • In wire, it is anywhere from 60% to 85% of c • a common type of cable used for cable TV has a propagation factor of 75% of c. Example 1 What is the wavelength in vacuum for a frequency of 1 million hertz? Example 2 What is the frequency when the measured wavelength is 6 m? Ya Bao
Frequency Range Designations --------------------------------------------------- 30 Hz‑----300 Hz ELF 0.3 kHz‑--3 kHz VF 3 kHz-----‑30 kHz VLF 30 kHz‑---300 kHz LF 0.3 MHz‑-3 MHz MF 3 MHz‑----30 MHz HF 30 MHz---300 MHz VHF 0.3 GHz‑--3 GHz UHF 3 GHz‑----30 GHz SHF 30 GHz‑---300 GHz EHF 0.3 THz‑---3 THz Infrared light 3 THz‑------30 THz Infrared light 30 THz‑----300 THz Infrared light 0.3 PHz‑---3 PHz Visible light 3 PHz‑-----30 PHz Ultraviolet light 30 PHz‑----300 PHz X‑rays 0.3 EHz‑---3 EHz Gamma rays 3 EHz‑------30 EHz Cosmic rays 1 kilohertz (kHz)= 103 Hz, 1 megahertz (MHz)= 1*106 Hz 1 gigahertz (GHz)= 1*109 Hz, 1012 : terahertz (THz); 1015 : petahertz (PHz); 1018 : exahertz (EHz); Ya Bao