Wireless Stereo Audio Communicator for Television Use

1
Wireless Stereo Audio Communicator for Television
Use

• Dec0202
• 12/10/2002
• Team Members Advisors/Clients
• Matthew Hamilton Dr. John Lamont
• Eric Hagen Prof. Ralph
  Patterson III
• Michael Swan
• Cory Van Wyngarden
• Brian Young

2
Presentation Outline

• Problem Statement
• Design Objectives
• End-Project Description
• Assumptions and Limitations
• Project Risks and Concerns
• Technical Approach
• Evaluation of Project Success
• Recommendations for Further Work
• Human and Financial Budget
• Lessons Learned
• Closing Summary

3
Problem Statement

• General Background
• Users desiring privacy
• Hearing impaired
• Technical Problem
• Transmission of audio data up to 25 feet
• Near line-of-sight reception
• Portable receiver
• Transmission of voice quality audio

4
Design Objectives

• Functionality
• Private listening of stereo television audio
• Analog FM transmission of audio using IR
• AC power at transmitter
• AC power and rechargeable batteries at receiver
• Tone control and balance capability
• Two sets of headphones and multiple receivers
• Volume can be individually adjusted

5
Design Objectives

• Design Constraints
• Transmission of audio up to 25 feet
• Receiver must be portable and easy to use
• Operating environment limited to indoor
  applications
• Minimal power consumption to improve battery life
• Low cost

6
Design Objectives

• Intended Users
• Individuals desiring private audio
• Hearing impaired
• Intended Uses
• Nursing home or hospital
• Dorm room
• Spouses in bedroom
• Broadcast situations

7
End-Product Description

• Wireless stereo audio through analog infrared
  transmission
• Lightweight and portable receiver
• External power supply
• Rechargeable battery in receiver
• Receiver with user controls
• Output via standard 3.5mm stereo jacks
• Input from televisions RCA output

8
Assumptions and Limitations

• Assumptions
• Television has RCA analog outputs
• User(s) will be viewing television while
  listening
• All needed parts and test equipment available
• Pricing by volume decreases overall cost estimate
• Minimal interference from other devices
• Limitations
• Lack of experience with wireless technology
• Real-time audio/video signal
• Limited time for development

9
Project Risks and Concerns

• Project specifications change
• Essential parts are unavailable or delayed
• Design has a terminal or serious fault
• Hardware is damaged or defective
• Loss of a group member

10
Technical Approach

• IR vs. RF
• Digital vs. analog transmission
• Alkaline vs. Nickel cadmium batteries
• DSB-SC modulation vs. two channel transmission

11
Technical Design
12
Evaluation of Project Success

• Milestones
• Project goals and target markets defined (fully
  met)
• Technology identified and selected (fully met)
• Product design (fully met)
• Product implemented (partially met)
• Testing and revision (partially met)

13
Recommendation for Further Work

• More compact design
• DSB-SC modulation (FM stereo)
• Single transmitter and single receiver boards
• Improve functionality
• Multiplexed stereo signal
• Digital transmission

14
Human Budgets
Final Team Effort
15
Financial Budget
Final Expenses
16
Lessons Learned

• Clearly defined project specs motivated team
  members
• Team members communicated well
• Part requests must be submitted early
• Practiced job related time management skills
• Utilized technical experts and other resources
• Expanded skills in analog circuit design and
  debugging

17
Closing Summary

• Wireless IR communication system
• For listening to television without disturbing
  others
• May be used by hearing impaired

18
Questions/Comments?
19
Appendix A
Receiver
20
Appendix B
Transmitter
Tone Control
Battery Recharging Circuit