ELCT 1003: High Speed Electronic Circuit
Lecture 1: Introduction
Dr. Mohamed Abd El Ghany,
Department of Electronics and Electrical Engineering
Course Objective
Give an introduction to the electronic circuit in
communication systems
Address the design of high frequency analog
building blocks like the current feedback
operational amplifiers, tuned amplifiers,
oscillators
Describe power characterization for high speed
electronic circuits
Discuss the design of A/D and D/A converter and
analyze the high speed A/D and D/A converters
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Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Text and Reference Books
Gray/Hurst/Lewis/Meyer, “Analysis and design of
analog integrated circuits,” John and Wiley & sons,
Inc, ISBN: 0-47L-32L68-0
Thomas H. Lee., “the Design of CMOS radio-
frequency integrated circuits,” Cambridge; New York,
Cambridge University Press, 1998
B. Razavi, “RF Microelectronics,” Prentice Hall PTR,
ISBN 0-13-887571-5
B. Razavi, “Design of Analog Integrated Circuits,”
McGraw-Hill , 1st edition, 2000
Journal papers
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Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Prerequisites
Semiconductors (ELCT 503)
Electronic Circuits (ELCT 604)
Microelectronics (ELCT 704)
4 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Administrative Rules
Course components:
Two Lectures
Sunday (First slot), (H9)
Sunday (Second slot), (H9)
Instructor: Dr. Mohamed A. Abd El Ghany
Grading:
Assignments: 20% (2 x 10%)
Research Projects : 20% (2 x 10%)
Mid term exam: 20%
Final exam: 40%
5 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Course Outline
Introduction
Frequency Response of Operational Amplifier
Current Feedback Op-Amp
High frequency Oscillators
Frequency Synthesizers
Power Distribution Network in High Speed Integrated Circuit
High Speed ADC and DAC
6 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Course Outline
Introduction
Frequency Response of Operational Amplifier
Current Feedback Op-Amp
High frequency Oscillators
Frequency Synthesizers
Power Distribution Network in High Speed Integrated Circuit
High Speed ADC and DAC
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Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Radio Communication Services
Radio broadcasting
TV broadcasting
Satellite
communication
Mobile telephony
Internet
And more ….
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Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Block diagram of a Radio Communication system
A radio communication system consists of a transmitter, a channel, and a receiver In a transmitter:
The input sound signal is converted into equivalent electrical current/voltage by a transducer.
The transducer output is amplified by chain of amplifiers (so that it can travel longer distance)
The purpose of the transmit antenna is to efficiently transform the electrical signal into radiation energy
In a receiver: The receive antenna efficiently accepts the radiated energy and convert it to an
electrical signal as the signal suffered attenuation during travel it requires further amplification
The output transducer converts the electrical signal back into sound energy
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Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Types of communication
A B • Simplex- A can talk to B
Radio, T.V. broadcasting
Simplest type, requires one transmitter and one receiver
• Duplex- A and B both can talk to each other
simultaneously
Telephone, Telegraph
Complex, requires two transmitter and two receiver at both
ends
Needs two different channels for simultaneous transmission
• half-Duplex- A and B can both talk to each other but not
simultaneously
Fax,
Needs one single channel for transmission
Compromise between two, don’t require separate
transmitter and receiver
Same antenna and circuitry may be used for both
transmission and reception
A B
A B
10 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Antenna Design
Antenna dimension ~ λ/2
For voice signal (f~ 3KHz)
λ = c/f = (3x108)/(3x103)= 100 km
D = λ /2 = 50 km ! Impossible to realize
11 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Modulation
Modulation is the process of
superimposing a signal(of
relatively low frequency) on a
high frequency signal(carrier
wave), which is more suitable
to transmit.
Demodulation is the
opposite function of
modulation, performed
at receiver side
12 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Modulation
The modulation process consists of:
Firstly, a varying current is produced when sound waves strike a
microphone.
Secondly, the microphone output is then fed into the modulator
circuit where the audio and carrier waves are combined.
13 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Modulation Types
Modulation
Digital Analog
Amplitude Modulation (AM)
Frequency Modulation (FM)
Phase Modulation (PM)
Amplitude Shift Key (ASK)
Frequency Shift Key (FSK)
Phase Shift Key (PSK)
14 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
AM/FM Modulation
In the FM process, the alternating
current from the microphone
modulates the carrier wave by
changing carrier wave’s
frequency.
In the AM process, the alternating
current from the microphone
modulates the carrier wave by
causing carrier wave’s amplitude
or strength to rise and fall.
15 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Carrier Frequency Bands
The carrier waves frequencies for radio
broadcasting are assigned by Federal
Communication Commission (FCC)
AM carrier frequency: 535 KHz to 1605
KHz
FM carrier frequency: 87.5 MHz to 108
MHz
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Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Carrier Frequency Bands Name Frequency
Range
Wave Length Application
ELF 300Hz to 3KHz 100Km to
1000Km
Navigation, long distance communication with ships
VLF 3KHz to 30KHz 10Km to
100Km
Navigation, long distance communication
LF 30KHz to
300KHz
1Km to 10Km Navigation, long distance communication with ships
MF 300KHz to 3MHz 100m to 1Km AM broadcasting, radio navigation
HF 3MHz to 30MHz 10m to 100m Radio broadcasting, fixed point to point (around the
world)
VHF 30MHz to
300MHz
1m to 10m Radio and TV broadcasting, mobile services
UHF 300MHz to 3GHz 10cm to 100cm Cellular telephony (GSM, NMT, AMPS). Digital TV,
fixed point-to-point, satellite, radar
SHF 3GHz to 30GHz 1cm to 10cm Broadband indoor systems, microwave links, satellite
communications
EHF 30 GHz to
300GHz
1mm to 10mm LOS communication (short distance or satellite)
17 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Managing Radio Spectrum
The frequency spectrum is common to all radio systems, so all radio
frequencies are regulated in order to avoid interference
International cooperation and regulations are required for an orderly
worldwide use of the radio spectrum
The international Telecommunication Union (ITU) is an agency part
of the united Nations that takes care of managing radio spectrum
worldwide.
With 184 membership countries, the ITU main activities are:
Frequency assignment
Standardization
Research
System compatibility issues
Coordination and planning of the international telecomm services
18 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
AM Transmitter
AM signals vary in amplitude in response to AF signals from the
microphone.
The AM modulator actually produces an output that includes the
carrier and two sidebands. These sidebands are mirror images of
each other and contain the same information.
The carrier and both sidebands are amplified by RF amplifier and
transmitted
19 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
FM Transmitter
Power
Amplifier AF Amplifier
Voltage
Controlled
Oscillator
The modulating signal, is a signal from the microphone. It is being
amplified in the AF amplifier and then led into the HF Voltage
Controlled Oscillator (VCO), where the carrier signal is being
created. The frequency of oscillator is changing in accordance with
the input voltage of oscillator. Therefore, the frequency modulation is
being obtained. The FM signal from the HF oscillator is being
proceeded to the power amplifier that provides the necessary output
power of the transmission signal.
20 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
AM Superheterodyne Receiver
The carrier frequency of any radio signal is converted to
intermediate frequency using mixer and local oscillator components.
A typical value of IF for an AM communication receiver is 455KHz.
RF
Amplifier
Local
Oscillator
Detector AF
Amplifier Mixer
IF
Amplifier
21 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
FM Superheterodyne Receiver
In FM receivers, a discriminator is a circuit designed to respond to frequency shift variations.
A discriminator is preceded by a limiter circuit, which limit all signals to the same amplitude level to minimize
noise interference.
The audio frequency component is then extracted by the discriminator, amplified in the AF amplifier, and used to
drive the speaker.
A typical value of IF for an AM communication receiver is 10.7MHz.
Local
Oscillator
Mixer IF
Amplifier
RF
Amplifier Limiter
Discrimi-
nator
AF
Amplifier
22 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Case Studies
Simplified architecture of Motorola’s FM receiver
The main components
of the Motorola’s FM
receiver are:
-Antenna
-LC matching network
-Mixer
-Bandpass Filter
-Voltage Controlled
Oscillator
-Crystal Oscillator
-Limiter
23 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering
Case Studies
Philips’DECT Transceiver
24 Dr. Mohamed Abd el Ghany
Department of Electronics and Electrical Engineering