DEC 2003

Electrical and Computer Engineering

Jeff Frolik, Assistant Professor

DEC 2003

Outline

• Where are electrical devices used?

• Fields within Electrical Engineering

• Exciting future for Electrical Engineers

• Wireless Communications (in your lifetime)

DEC 2003

Where are Electrical Devices Used?

• Home

• Office

• Medical

• Military

• Manufacturing

• Power

DEC 2003

Home

• Television

• VCR

• Remote Control

• Antenna

• Clock Radio

• Audio Compact Disk

• Home Computer

• Electric Stove

• MP3 Player

• Electric Water Heater

• Microwave Oven

• Video Games

DEC 2003

Work Place

• Desktop PC

• Laptop PC

• Copy/Fax Machine

• Computer Network

• Video Conferencing

• Cellular Telephone

• Supercomputers

DEC 2003

Medical

• Ultrasonics

• MRI Imaging

• CAT scan

• EKG

• EEG

• Digital Thermometers

DEC 2003

Military

• Radar

• Guided Missile

• Smart Bomb

• Aerospace Electronics

• Autopilot/UAV

• Infrared Imaging

• Digital Image Processing

• Satellite

• Global Positioning System

DEC 2003

Manufacturing

• Robotics

• Inventory Control

• Visual Inspection System

• Electronic Instrumentation

• Computer-controlled Processes

• Semiconductors

• Electric Welding

• Laser Cutting

• Computer Integrated Manufacturing

http://www.extremepumpkins.com/detsciencen.html

DEC 2003

Power Systems

• Power Generator

• Motor

• Transformer

• Transmission Line

• Distribution System

• Alternative Energy Sources

DEC 2003

Where are Electrical Devices Used?

EVERYWHERE!

DEC 2003

Fields within Electrical Engineering

• Aerospace Electronics

• Antennas

• Broadcast Technology

• Circuits and Systems

• Communications

• Computers

• Consumer Electronics

• Control Systems

• Education

• Electromagnetics

• Industrial Electronics

• Instrumentation

DEC 2003

More Fields within Electrical Engineering

• Lasers

• Magnetics

• Microwave

• Plasma Science

• Power Electronics

• Reliability

• Robotics

• Semiconductors

• Signal Processing

• Ultrasonics

• Vehicular Technology

DEC 2003

Exciting Future for Electrical and Computer Engineers

• High Definition TV

• Superconductors

• Smart Weapons

• Supercomputers

• Electric Cars

• Micromotors

• Sensing Computers

• Virtual Reality

• Microelectromechanical Systems (MEMS)

• Video Phones

• Lasers

• Clean Power Sources

• Smart Cars

• Smart Robots

• Computer Vision

DEC 2003

Wireless Communications During Your Lifetime (So Far!)

DEC 2003

Wireless Communication Systems: WHY?

Camel’s Hump School survey:

1. Better what?

2. Better what?

3. Better what?

DEC 2003

Wireless Communication Systems: WHY?

Wired transmission media - wire/fiber

Wireless transmission media - air

• Quick installation of infrastructure • e.g., straight to mobile in developing countries

• User mobility • Shared access of channel (airwaves)

DEC 2003

Today’s Talk

WLAN

Your life (thus far)

DEC 2003

Frequency Spectrum

How is the “air” shared?

Different applications use different frequency bands:

• AM radio: 530-1600 kHz• FM radio: 88-108 MHz• TV: CH 2-13: 54-88 & 178-216 MHz

CH 14-83: 470-890 MHz• Cellular: 824-894 MHz• Cellular PCS: 1.8-2.0 GHz• Wi-Fi: 2.45-2.50 GHz, 5.725-5.875 GHz• DBS Satellite: 12.2-12.7 GHz

Note: the higher you go in frequency, the more “room” you have

Spectrum Analyzer

DEC 2003

Mobile Communications

Two-way Radio

1. Pro

2. Pro

3. Con

4. Con

Cell Phone

1. Pro

2. Pro

3. Con

4. Con

DEC 2003

1G Cellular Systems (1983)

“Advanced” Mobile Phone System (AMPS)

• Limited coverage: few cell towers

• Channelized analog system

What was wrong with it?

DEC 2003

1G Cellular Systems (1983)

“Advanced” Mobile Phone System (AMPS)

• Limited coverage: few cell towers

• Channelized analog system

What was wrong with it?

Hint: What is the biggest component in your cell phone?

DEC 2003

1G Cellular Systems (1983)

“Advanced” Mobile Phone System (AMPS)

• Limited coverage: few cell towers

• Channelized analog system

Question what was wrong with it?

Battery Killer

• Few sites – further distance to transmit

• Analog system – always sending a signal during call

DEC 2003

The Fix

Demand for service

• Increased coverage area

• Increase cell density

Advances in digital technology

• 2G systems (1993)

• Digital systems compress and send “data” as available

Result: more efficient use of batteries

• Less distance to send

• Less time sending

DEC 2003

What’s next?

3G systems

• Voice

• Internet

• Music

• Video

• Games

Images courtesy: Motorola

DEC 2003

What’s next?

3G systems

• Voice

• Internet

• Music

• Video

• Games

Images courtesy: Motorola

Problem?

DEC 2003

What’s next?

3G systems

• Voice

• Internet

• Music

• Video

• Games

Images courtesy: Motorola

Problem: more time on per hour results in shorter battery life

DEC 2003

Television Broadcasting

• Terrestrial Broadcast TV

• An analog system of limited range

• Each channel occupies 6 MHz

• Regular Cable: same technology, just over wire

• Need for an alternative?

• Cable not available everywhere

• Cable had a “monopoly”

• Analog system had a limited number of channel (82)

DEC 2003

Satellite Broadcast Television

HUB

Shaped pattern

22,400 miles

DEC 2003

Direct to Home Satellite TV (1986)

C-band (4 GHz)

• 6 foot dishes

Analog system

• 6 MHz channels

• Few channels per satellite

Image: Dave’s Web Shop

DEC 2003

Direct to Home Satellite TV (1986)

C-band (4 GHz)

• 6 foot dishes

Analog system

• 6 MHz channels

• Few channels per satellite

Image: Dave’s Web Shop

Problems?

DEC 2003

Direct to Home Satellite TV (1986)

C-band (4 GHz)

• 6 foot dishes

Analog system

• 6 MHz channels

• Few channels per satellite

Image: Dave’s Web Shop

Problems:• cumbersome/expensive equipment• expensive hardware• limited channel selection

DEC 2003

DBS Receiver Technology

• Ku-band (higher frequency) enables small receiving dish

• Digital signal provides

• CD quality sound

• “Better” picture

• Additional services

• More channels: “500!”

DEC 2003

DBS Summary

• Promise of high-quality, nation-wide service obtained• DirecTV and Echo Star

• Advantages• Easy to add new customers (database change)

• Disadvantages• Large customer and venture investment up-front• No standard among providers• Compression can break down• Cable has caught up• Limited bandwidth, HDTV? • Rainfade (FL - high gain slope and rain rates)

DEC 2003

Satellite Radio (2002)

• Two competing and incompatible systems: XM and Sirius

• Like Direct Broadcast Television in idea

• Smaller antenna

• No need to point

• Coming next, Digital Radio in the AM and FM bands.

• Static free

• Additional features (e.g., play list)

Image: Sony

DEC 2003

Iridium (1998)

• Cell coverage around the world through a 66 satellite network• Low earth orbit: 485 miles

• First phones were brick size/weight• Pricing is way too high (dollars/minute) for

general consumer• Land based systems in other countries built

out faster than expected• $4 B and company filed for bankruptcy• Niche market for private planes, boats, artic

explorers and military

• Lesson learned (probably not): Just because you can do something, doesn’t mean you should

Source: Iridium

DEC 2003

Wireless Networks (2000)

Laptop Laptop

Laptop

Network

W-LAN

802.11 b (WI-FI)

Slave-PDA

Slave-Cell

Slave-Laptop

Master-Car

W-PAN

Bluetooth

DEC 2003

Bluetooth - PAN

• In the office

• In the car

• Soda machine

DEC 2003

Coverage Area in Wireless

                                                            Source: University of Kansas' Information & Telecommunications Technology Center and Kansas Applied Remote Sensing Program

Not uniform in practice

DEC 2003

So what is happening now!

TODAY: 10 million users in the US check mail or surf the web wirelessly via mobile phones or handheld computers

• WLAN• 802.11b (11 Mbps) and Bluetooth (720 kbps)

• Satellite based systems• XM and Sirius digital radio• OnStar telematics

• In building wireless• Your mobile phone becomes part of the company exchange inbuilding• Maintains regular mobile functions off-campus

• THE FIELD IS MARKET DRIVEN!

DEC 2003

What is Next? Wireless Sensor Networks

Very sophisticated, low-cost and ubiquitous sensing networks using many, broadly distributed sensors

NETWORK

3G, WLAN

DEC 2003

Very sophisticated, low-cost and ubiquitous sensing networks using many, broadly distributed sensors

The system is sophisticated but the individual components can be “dumb”

Wireless Sensor Networks

DEC 2003

Why is this an important area?

Industry~90% of instrumentation costs deal with installation

(e.g., mounting and routing of cabling)

MilitaryCan sensor systems replace human sentinels and save lives?

EnvironmentalIn situ sensing is more accurate than remote sensing

DEC 2003

Sample Wireless Sensor Application:Smart Bobbers

• Ubiquitous sensing of watershed

processes (e.g., chemicals,

hydrology and nutrients)

• Fully integrated floating sensing,

processing and communicating

device

• Information enables dynamic

modeling and adaptive

management of resources

Data Reception & Sensor Fusion

DynamicModeling

Adaptive Management

Watershed

CN

HH

HN

N CC

DEC 2003

DEC 2003

End Result:Remote

Monitoring of Spatial-

Temporal Data

http://quake.wr.usgs.gov/recenteqs/latest.htm

DEC 2003

Student Project - Hardware

DEC 2003

Math is Important!

• FM modulation

)sin()(!3

1)cos()(

!2

1)sin()(cos

))(cos())(cos()(

2222 ttakttakttaktA

taktAdmktAt

cfcfcfc

fc

t

fcFM

CALCULUS – Power Series Expansion

DEC 2003

Communications is Important!

• Engineers must be able to communicate their ideas

• To their colleagues/clients

• In written reports

• In oral presentations

DEC 2003

Key Points

• Electrical Engineers work in all aspects of society

• In less than 20 years, wireless communications has become nearly ubiquitous

• Technology without a market is doomed to fail

• Your math courses and communication skills form a key foundation for electrical engineering

• The future is up to you!