Download Systems Overview - University of Hawaii

Department of Electrical
Engineering
Systems
What is Systems?
The study of mathematical and engineering tools used
to analyze and implement engineering systems
• Communications
• Networks
• SignalProcessing
• Control
History
• A. G. Bell: scientist and inventor (telephone, Bell
Telephone Co., communication devices)
• T. Edison: inventor and businessman (electric light
bulb, power distribution systems, media inventions)
• H. Nyquist: engineer (stability of feedback
amplifiers, sampling theorem)
• C. Shannon: EE and mathematician (information
theory, communications, sampling theorem)
• J. Kilby: EE ( inventor of IC, precursor for
development of signal processors and DSP)
Communications
``Transfer and organization of information, of diverse
media types and formats, through communication
networks and channels ’’
IEEE Communications Society
Networks
``A computer network is a system for communication
among two or more computers.
• Computer networks may be categorized with respect to
range
• Computer network applications may be categorized with
respect to the functional relationships between components
• Computer networks may be categorized with respect to
network topologies
• Computer networks may be categorized with respect to
specialized functions’’
Wikipedia
Signal Processing
``The theory and application of
filtering, coding, transmitting, estimating, detecting,
analyzing, recognizing, synthesizing, recording, and
reproducing signals
by digital or analog devices or techniques.
“Signal" includes audio, video, speech, image,
communication, geophysical, sonar, radar, medical,
musical, and other signals’’
IEEE Signal Processing Society
Controls
``The theory, design and application of Control Systems.
It shall encompass components, and the integration of
these components, as are necessary for the
construction of such systems.
The word `systems' as used herein shall be interpreted to
include physical, biological, organizational and other
entities, and combinations thereof, which can be
represented through a mathematical symbolism’’
IEEE Control Systems Society
EE Systems Curriculum
• Core EE Classes
– Tools Courses:
• EE315 Signals and Systems
• EE342 Probability and Statistics
– EE341 Intro. to Communications
• Core Systems Classes
– EE351 Linear Systems and Control
– EE415 Digital Signal Processing
• Elective Classes
Signal Representation
Signals represent physical phenomena. Different ways of
representing information from a signal.
Time Domain
Frequency Domain
Signal Manipulation
x(t)
System
y(t)
Signals manipulated by passing them through systems
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Filtering
Estimation
Coding
Transmission
Extraction
Conversion
Analog to Digital Conversion
Analog signal
Continuous time
Analog value
Digital Signal
A/D
Sampler
Quantizer
Discrete time
Analog value
Discrete time
Binary value
Analog and Digital Signals
Probability Application
Recovery of Information Signals
Many physical processes modeled by random phenomena
• x(t) is input signal containing information.
• y(t) is signal corrupted by random noise, distortion from
channel, and interference from other information signals.
• z(t) is output signal that gets estimate of information x(t).
x(t)
Channel
Noise
y(t)
Receiver
z(t)
Receiver is designed using tools from probability,
systems, and communications to optimize desired
criteria (Signal to Noise Ratio, Probability of error)
Digital Communications Systems
Source
Source
Encoder
Channel
Encoder
Transmitter
Channel
Destination
Source
Decoder
Channel
Decoder
Receiver
Multiplexing problem
Time
CDM
Frequency
TDM
Frequency
Frequency
FDM
Time
Time
Several information users share common
channel. How to multiplex information
FDM: analog signals, optical fiber (WDM)
TDM: digital signals, cellular phones
CDM: cellular phones, 3G
Jobs in Systems Area
• Telecommunications
– AT&T, Cisco
• Defense
– Lockheed Martin, Boeing, Northrup Gruman, Raytheon
• Computers
– Microsoft, HP, Apple
• Electronics
– Motorola, Intel
• Startups
Homework Problem
Pick one topic from below and use internet resources to write a
short report ( 1 to 2 pages) on how systems technology will
impact the following areas:
• 3G communications
• Sensor networks
• Bioinformatics
In your report please reference all web sites.
- Define topic and why it is important
- Key technological problems and how systems can help
- Key players in area
- Your interests in area