This book helps systems engineers, designers, and managers in TV broadcasting make a smooth transition from analog to digital technologies. With an emphasis on RF transmission rather than baseband signal processing, it offers in a single resource a complete discussion of the digital TV signal, from the input to the transmitter to the output of the receiving antenna.
Industry expert Gerald Collins provides clear, up–to–date explanations that build upon experience engineers already have with analog technology, including comparisons between analog and digital systems, factors affecting the performance of VHF and UHF stations, and down–to–earth discussions of modern high–power RF filters. Plus, he provides over 150 high–quality illustrations and tables as well as extensive references for readers wishing to pursue the subject more in depth. The discussion includes:
∗ Major digital TV transmission standards
∗ Key performance parameters of interest to RF engineers
∗ The theory of operation and practical implementation of major system components
∗ Factors affecting propagation of digital TV signals
∗ Results of field testing of DTV systems
∗ Performance data on the American ATSC, the European DVB, and the Japanese ISDB–T systems
The DTV waveform shown on the cover was photographed by Bob Plonka of Harris Corporation and is used with permission.
1. Digital Television Transmission Standards
ATSC terrestrial transmission standard, vestigial sideband modulation, DVB–T transmission standard, ISDB–T transmission standard, channel allocations, antenna height and power, MPEG–2
2. Performance Objectives for Digital Television
System noise, external noise sources, transmission errors, error vector magnitude, eye pattern, interference, cochannel interference, adjacent channel interference, analog to digital TV, transmitter requirements
3. Channel Coding and Modulation for Digital Television
Data synchronization, randomization/scrambling, forward error correction, interleaving, inner code, frame sync insertion, quadrature modulation, 8 VSB, bandwidth, error rate, COFDM, flexibility, bandwidth
4. Transmitters for Digital Television
Precorrection and equalization, up conversion, precise frequency control, RF amplifiers, solid–state transmitters, RF amplifier modules, power supplies, power combiners, Wilkinson combiner, ring combiner, starpoint combiner, cooling, automatic gain or level control, ac distribution, transmitter control, tube transmitters, tube or solid–state transmitters, performance quality, retrofit of analog transmitters for DTV
5. Radio–Frequency Systems for Digital Television
Constant–impedance filter, output filters, elliptic function filters, cavities, channel combiners
6. Transmission Line for Digital Television
Fundamental parameters, efficiency, effect of VSWR, system AERP, rigid coaxial transmission lines, dissipation, attenuation, and power handling, higher–order modes, peak power rating, frequency response, standard lengths, corrugated coaxial cables, wind load, waveguide, bandwidth, waveguide attenuation, power rating, frequency response, size trade–offs, which line? waveguide or coax? pressurization.
7. Transmitting Antennas for Digital Television
Antenna patterns, elevation pattern, mechanical stability, null fill, azimuth pattern, slotted cylinder antennas, gain and directivity, power handling, antenna impedance, bandwidth and frequency response, multiple–channel operation, types of digital television broadcast antennas, antenna mounting
8. Radio–Wave Propagation
Free–space propagation, distance to the radio horizon, refraction, multipath, ground reflections, surface roughness, effect of earth s curvature, Fresnel zones, linear distortions, diffraction, fading, undesired signal, field tests, Charlotte, North Carolina, Chicago, Illinois, Raleigh, North Carolina
9. Test and Measurement for Digital Television
Power measurements, average power measurement, calorimetry, power meters, peak power measurement, measurement uncertainty, testing digital television transmitters
Symbols and Abbreviations.