Radio Frequency Radiation (RFR)
Digital Television (DTV) and RFR

Digital Televition (DTV) will bring increased clarity of television signals, and may permit the introduction of new digital services on conjunction with television transmission. However, DTV transmitters and antennas differ fundamentally from NTSC (existing) transmitters in terms of average and peak radiated power. To quote Dielectric Communications, Inc. "NTSC power levels are relative to peak sync while DTV powers are average.
DTV has peak signal levels 4-5 times (6-7 dB) greater than average. The transmitter must be sized to pass these
peak levels with minimum distortion. Therefore, to equate DTV transmitter sizes to NTSC transmitters it is
necessary to multiply the DTV power by 5
."

  • Dielectric Communications points out that DTV peak radiated power is 5 times greater than standard NTSC (existing) signals. "The interference that extreme power will bring to adjacent channels and mobile radio has not been fully researched. For example, the protection ratios published by the FCC should be applied at the receiver, not at the transmitter. Nor has the issue of average and peak RF hazard levels been adequately researched. The actual RF hazard levels may yet prove to be in conflict with the FCC’s own guidelines. Once understood, the interference and RF levels may well impose additional constraints on service replication."
  • The Advanced Television Systems Committee (ATSC) was formed to establish voluntary technical standards for advanced television systems, including digital high definition television (HDTV).
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