Overcoming and obstacle to broadcasting the gospel

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(No Transcript)
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Improving Broadcast Coverage With DRM

• Charlie Jacobson and John Wineman
• HCJB Global Technology Center
• 5/8/2008

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NVI Tropical Band Shortwave

• Advantages
• Coverage 100 to 300 Miles

• Disadvantages

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NVI Tropical Band Shortwave

• Advantages
• Coverage 100 to 300 Miles

• Other Considerations
• Frequency schedule required
• Audio Quality
• Transmitter, Receivers and antennas are
• More expensive
• Less available
• More complex

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NVI DRM Tropical Band Shortwave

• Advantages
• Coverage 100 to 300 Miles

• Other Considerations
• Frequency schedule required
• Audio Quality
• Transmitter, Receivers and antennas are
• More expensive
• Less available
• More complex

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NVI DRM Tropical Band Shortwave

• Advantages
• Coverage 100 to 300 Miles
• Audio Quality

• Other Considerations
• Frequency schedule required
• Transmitter, Receivers and antennas are
• More expensive
• Less available
• More complex

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FM

• Advantages
• Audio Quality
• Transmitters, Receivers and Antennas are
• Less expensive
• More available
• Less complex
• Easier to maintain

• Other considerations
• Typical coverage 35 Miles
• Requires a network of FM stations for greater
  coverage

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FM Network

• Advantages
• Audio Quality
• Receivers are
• Less expensive
• More available
• Less complex
• Easier to maintain
• Larger audience
• Programming can include local languages and
  events

• Other considerations
• Requires more transmitters for the same coverage
  as Tropical Band Shortwave
• The broadcast network is
• More expensive
• More complex
• Harder to maintain

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FM NVI Tropical Band Shortwave

• Advantages
• Larger audience
• Greater coverage

• Other considerations
• The broadcast network is
• More expensive
• More complex
• Harder to maintain

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FM Network interconnections

• Required for networks with a master studio
• Sends program audio to remote transmitters

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FM Network InterconnectionsTape Distribution

• Simplest (Snail mail, motorcycle, foot)
• Precludes real time program content
• Minimal capital investment
• May be be more expensive in the long term

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FM Network InterconnectionsFM Relay

• Requires stations every 30 miles or closer
• Only as good as the weakest link in the chain
• Requires a more complex license

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FM Network InterconnectionsOther methods

• Phone lines
• Internet
• Point to multipoint link (studio/transmitter
  link)
• Satellite
• DRM

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FM Network InterconnectionsUsing DRM

• Advantages
• 100 to 300 mile coverage
• Works over the horizon
• Works in mountains
• Clear audio
• Program is received on
• Fm
• Shortwave
• Larger Audience

• Other considerations
• Increased network complexity
• Additional equipment required
• HF transmitter near the studio
• DRM Receiver at each remote FM transmitter
• Shortwave propagation vs. frequency still an
  issue

FM
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FM Network InterconnectionsUsing a Diversity
DRM Receiver

• Advantages
• 100 to 300 mile coverage
• Works over the horizon
• Works in mountains
• Clear audio
• Program received on
• Fm
• Shortwave Frequency 1
• Shortwave Frequency 2
• Larger Audience
• Higher reliability

• Other considerations
• Increased network complexity
• Additional equipment required
• HF transmitter near the studio
• Diversity DRM Receiver at each remote FM
  transmitter
• A Second HF transmitter near the studio

FM
SW Freq. 1
SW Freq. 2
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Diversity DRM Receiver Project Team

• Project partners
• HCJB Global Technology Centers International
  Broadcast Team Elkhart IN
• Letourneau University Longview TX
• Rockwell Collins Cedar Rapids, IA

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07-08 Achievements

• Refined DRM receiver requirements
  specifications
• Developed specifications for the DDC modules
  (Preselector, VGA, ADC and FPGA)
• Developed the module interface requirements
  specifications
• Developed test plans for each DDC Module

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07-08 Achievements

• Designed hardware for the DDC modules
• Conducted Design Review and periodic status
  review meetings
• Built Prototypes of each DDC module
• Tested DDC modules
• Documented final design, project results
  lessons learned

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08-09 Objectives

• Finalize and publish DRM receiver demodulator
  requirement specifications
• Publish design documentation for each component
• Integrate the existing hardware components
• Investigate, design, and begin implementation of
  digital demodulator
• Research hardware and software diversity
  techniques

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Diversity DRM Receiver Project

• Questions?