Data Communication Theory & Coding

http://eent3.lsbu.ac.uk/staff/baoyb/dctc

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Website:http://eent3.lsbu.ac.uk/staff/baoyb/dctchttp://www.lsbu.ac.uk/bb/

Methods of Teaching and Learning : Lectures, Tutorials and WorkshopsAssessment of the Module :2-hour written examination -- 70% Laboratory report -- 30% Lecturer: Ya Bao and J G ZhangLab tutor: Ya Bao and Vincent Siyau.Ya Bao

Text Books

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Chapter 1. Introduction

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table_01_01a

table_01_01a1.1 Historical Background

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1.2 The Block Diagram of a Communication Systems

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1.3 Channel Characteristics

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Types of transmission channels

• Electromagnetic wave propagation channels (wireless)• Guided electromagnetic wave

channels (wired)• Optical links

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1.4 System analysis techniques

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a.Time-domain and frequency-domain analysesSignal frequency and signal bandwidth, Fourier Analysis

b.Modulation and communication theoriesChanging some parameter of a carrier wave in accordance with the message signal.

c. Detection theoryd. Probability theory

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1.5 The Electromagnetic Spectrum1. 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

frequencyvelocitywavelength

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Wavelength can also be measured as the distance between the negative peaks, zero points.

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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 1What is the wavelength in vacuum for a frequency of

1 million hertz?Example 2What is the frequency when the measured

wavelength is 6 m?

smc /103 8

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1.6 THE ELECTROMAGNETIC SPECTRUM

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Frequency Range Designations---------------------------------------------------

30 Hz‑----300 Hz ELF 0.3 kHz‑--3 kHz VF3 kHz-----‑30 kHz VLF 30 kHz‑---300 kHz LF 0.3 MHz‑-3 MHzMF3 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 light3 THz‑------30 THz Infrared light30 THz‑----300 THz Infrared light0.3 PHz‑---3 PHz Visible light3 PHz‑-----30 PHz Ultraviolet light30 PHz‑----300 PHz X‑rays0.3 EHz‑---3 EHz Gamma rays3 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);