Department of Electrical Engineering

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• Department of Electrical Engineering
• Systems

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What is Systems?

• The study of mathematical and engineering tools
  used to analyze and implement engineering systems
• Communications
• Networks
• SignalProcessing
• Control

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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)

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Communications

• Transfer and organization of information, of
  diverse media types and formats, through
  communication networks and channels
• IEEE Communications Society

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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

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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

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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

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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

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Signal Representation
Signals represent physical phenomena. Different
ways of representing information from a signal.
Time Domain
Frequency Domain
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Signal Manipulation
System
y(t)
x(t)

• Signals manipulated by passing them through
  systems
• Filtering
• Estimation
• Coding
• Transmission
• Extraction
• Conversion

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Analog to Digital Conversion
A/D
Digital Signal
Analog signal
Sampler
A/D
Continuous time Analog value
Discrete time Binary value
Discrete time Analog value
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Analog and Digital Signals
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Probability ApplicationRecovery 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).

Channel
Receiver
x(t)
y(t)
z(t)
Receiver is designed using tools from
probability, systems, and communications to
optimize desired criteria (Signal to Noise Ratio,
Probability of error)
Noise
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Digital Communications Systems
Source Encoder
Transmitter
Channel Encoder
Source
Channel
Source Decoder
Receiver
Channel Decoder
Destination
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Multiplexing problem
FDM
TDM
CDM
Frequency
Frequency
Frequency
Time
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
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Jobs in Systems Area

• Telecommunications
• ATT, Cisco
• Defense
• Lockheed Martin, Boeing, Northrup Gruman,
  Raytheon
• Computers
• Microsoft, HP, Apple
• Electronics
• Motorola, Intel
• Startups

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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