Technology - Digital Broadcasting 1 - Trends and Frequencies

Synopsis

As a prelude to detailed discussion of the various digital broadcasting technologies, we review the propagation of radio waves, the established analogue broadcasting techniques and the resulting spectrum management arrangements in which digital broadcasting takes place. We summarise the key technical and commercial trends and principles we believe characterise the digitisation of broadcasting.

Table of Contents

• 1. Synopsis
  
• 2. Introduction
  
• 3. Analogue vs digital broadcasting
  
  • 3.1 Multi-channel and multi-purpose
    
  • 3.2 Dynamic bandwidth allocation
    
  • 3.3 Quality trade-offs
    
  • 3.4 Storage and replay
    
  • 3.5 Flexibility of playback
    
  • 3.6 Encryption and conditional access
    
  • 3.7 User control and diversity
    
  • 3.8 Digital Rights Management (DMR)
    
  • 3.9 Interactivity and eCommerce
    
  • 3.10 Competition with increased numbers of channels
    
  • 3.11 Integration with Internet delivery
    
  • 3.12 Interactivity and datacasting
    
  • 3.13 Single frequency networks
    
  • 3.14 Satellite and terrestrial
    
  • 3.15 Fixed and mobile
    
• 4. Frequency, wavelength and propagation
  
  • 4.1 Electromagnetic radiation
    
  • 4.2 Amplitude and frequency modulation
    
    • 4.2.1 Sidebands carry the information
      
  • 4.3 Health aspects of electromagnetic radiation
    
  • 4.4 Propagation and antennae
    
    • 4.4.1 Frequency limits of electronics
      
    • 4.4.2 Multipath reception
      
    • 4.4.3 Diffraction
      
• 5. Analogue TV and radio
  
  • 5.1 NTSC and PAL analogue TV
    
  • 5.2 Propagation and business models
    
    • 5.2.1 Medium Wave AM radio
      
    • 5.2.2 Shortwave AM radio
      
    • 5.2.3 VHF TV and FM radio
      
    • 5.2.4 UHF TV
      
    • 5.2.5 Single signal – single transmitter
      
    • 5.2.6 Overhead in establishing a transmitter
      
• 6. ITU recommendations
  
• 7. Related reports
  

• Exhibit 1 – Propagation and antennae characteristics of wavelengths used in broadcasting
• Exhibit 2 – ITU recommendations for digital broadcasting