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Lecture 1: Introduction
ECE 302, 2nd Semester 2015/2016 Communication Engineering ECE 324, 2nd Semester 2015/2016 Theory of Communication Dr.-Ing. Saleh Hussin Lecture 1: Introduction Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Instructor : Dr.-Ing. Saleh Hussin saleh@zu.edu.eg
Lectures : Tues :30 – 3:00 Room (27319) Office: Room 27406 Office Hours : Sun.: 9:00 – 15:00 Tues..: 9:00 – 15:00 Teaching Assistants: Eng.: Mohammed Ayesh, Duration : 14 weeks Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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About the Course No Specific reference for the course
Just follow the course notes ( Other reference may be given ECE 324, 3rd ECE Theory of Communication ECE 302, 3rd CSE Communication Engineering Lecture 3 credit hours 4 credit hours Exercise 2 credit hours Exam 3 Hours Grading Midterm 45 Final Exam 80 105 Total 125 150 Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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About the Class Classroom Protocols: You’r welcome to ask questions
Always be on time No side conversation No cellphones ringing You’r welcome to ask questions You can interrupt me at any time Our responsibility is to facilitate your learning. You have to make the effort If you have a question on the lecture material, then Look up a book. Ask me during my office hours, or me at anytime Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Course content Fourier Series and Transformation
Amplitude Modulation Techniques Amplitude Modulation & Demodulation Circuits Angle Modulation Techniques Detection of Frequency & Phase Modualation Signal Pulse Modulation The effect of Noise Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Brief History of Communication Systems
1844: Telegraph 1876: Telephony 1904: Radio : Television: 1936: FM radio : World War II Radar and microwave systems :Information Theory and coding. C. E. Shannon 1962: Satellite communications begins. : High Speed digital communication 1972: Motorola develops cellular telephone. Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Communication Systems
Transmitter: modifies the signal for efficient transmission. Channel: medium in which the modified signal is sent. Receiver: reprocesses the signal to get estimation of the transmitted signal. Noise Data s(t) Data r(t) Transmitter Channel Receiver Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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To be transmitted, Information (Data) must be transformed to electromagnetic signals.
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Electromagnetic Waves
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Types of Signals Analog: Digital
Continuous-valued of amplitude continuous-time signal Digital Fixed values of amplitude Signals can be analog or digital. Analog signals can have an infinite number of values in a range; digital signals can have only a limited number of values. Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Amplitude Modulation (AM)
Modulation Types Modulation Types Digital Modulation bit stream ( ) Analogue Modulation Pulse Modulation Analogue Modulation Angle Modulation Amplitude Modulation (AM) Frequency Modulation FM Phase Modulation PM Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Modulation Types Modulation Types Digital Modulation
bit stream ( ) Analogue Modulation Pulse Modulation Pulse Modulation Pulse Code Modulation PCM Pulse Amplitude Modulation (PAM) Pulse Width Modulation Pulse Duration Modulation PWM/PDM Pulse Position Modulation PPM Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Modulation Types Modulation Types Digital Modulation
bit stream ( ) Analogue Modulation Pulse Modulation Digital Modulation Amplitude Shift Key (ASK) Frequency Shift Key (FSK) Phase Shift Key (FSK) Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Frequencies for Communication
Universität Karlsruhe Institut für Telematik Mobilkommunikation SS 1998 Frequencies for Communication twisted pair coax cable optical transmission 1 Mm 300 Hz 10 km 30 kHz 100 m 3 MHz 1 m 300 MHz 10 mm 30 GHz 100 m 3 THz 1 m 300 THz VLF LF MF HF VHF UHF SHF EHF infrared visible light UV VLF = Very Low Frequency UHF = Ultra High Frequency LF = Low Frequency SHF = Super High Frequency MF = Medium Frequency EHF = Extra High Frequency HF = High Frequency UV = Ultraviolet Light VHF = Very High Frequency Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin Prof. Dr. Dr. h.c. G. Krüger E. Dorner / Dr. J. Schiller
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Frequencies for Communication
VHF-/UHF-ranges for mobile radio simple, small antenna for cars deterministic propagation characteristics, reliable connections SHF and higher for directed radio links, satellite communication small antenna, beam forming large bandwidth available Wireless LANs use frequencies in UHF to SHF range some systems planned up to EHF limitations due to absorption by water and oxygen molecules (resonance frequencies) weather dependent fading, signal loss caused by heavy rainfall etc. Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Radio Wave Propagation Modes
Ground Wave Propagation Follows contour of the earth Can Propagate considerable distances Frequencies up to 2 MHz Example : AM radio Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Radio Wave Propagation Modes
Sky Wave Propagation Signal reflected from ionized layer of atmosphere. Signal can travel a number of hops, back and forth Examples: Radio Line-of-Sight Propagation Transmitting and receiving antennas must be within line of sight Example: Satellite communication Ground communication Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Periodic Signals In communication systems, we commonly use periodic analog signals. Periodic signals can be classified as simple or composite. A simple periodic signal, a sine wave, cannot be decomposed into simpler signals. Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Periodic Signals A composite periodic signal is composed of multiple sine waves. Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Periodic Signals A single-frequency sine wave is not useful in data communications; we need to send a composite signal, a signal made of many simple sine waves. According to Fourier analysis, any composite signal is a combination of simple sine waves with different frequencies, amplitudes, and phases. Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Fourier Series Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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How we Deal with Signals ?!!!!
Amplitude Modulation Frequency / Phase Modulation Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Fourier Transform The frequency domain is more compact and useful when we are dealing with more than one sine wave. Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Revision Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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The Mathematic Formulation
Any function that satisfies where T is a constant and is called the period of the function. Example: Find the period Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Example 1: smallest T Fact: 2016-02-16
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Example 2: must be a rational number 2016-02-16
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Example 2: not a rational number Is this function a periodic one?
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T is a period of all the above signals
Fourier Series T is a period of all the above signals Trigometric Form Let 0=2/T. Even Part Odd Part DC Part Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Decomposition Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Function Properties 2016-02-16
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Function Properties 2016-02-16
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Harmonics Define , called the fundamental angular frequency.
Define , called the n-th harmonic of the periodic function. Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Orthogonal Functions Call a set of functions {k} orthogonal on an interval a < t < b if it satisfies Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Orthogonal set of Sinusoidal Functions
Define 0=2/T Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Proof If m n Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Proof If m = n Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Example (Square Wave) f(t) 2 3 4 5 - -2 -3 -4 -5 -6 1
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T is a period of all the above signals
Trigometric Form T is a period of all the above signals Even Part Odd Part DC Part Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Complex Exponentials 2016-02-16
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Complex Form of the Fourier Series
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Complex Form of the Fourier Series
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Complex Form of the Fourier Series
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Complex Form of the Fourier Series
If f(t) is real, Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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Thanks for your attention
Electronics and Communication Engineering Department Dr.-Ing. Saleh Hussin
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