Direct television broadcasting with a medium-size satellite

摘要

The low-risk, high reliability DBS (direct broadcasting satellite) design approach that led to the world's first DBS delivery-in-orbit type contact is described relative to the unique TWTA (traveling-wave-tube amplifier), redundancy, and battery technology used on the medium-size Hughes HS 376 spacecraft. The general DBS technical and commercial problems that have been encountered worldwide to date are summarized. DBS coverage of Great Britain, Japan, Saudi Arabia, Switzerland, Thailand, and the US are considered, as is the community broadcasting satellite service to Australia's remote outback via Aussat's existing HS 376 satellite system. Edge-of-coverage effective isotropic radiated power from 47 to 59 dBW is identified and the varying 7-to-15 year lifetimes resulting from different booster capabilities that have been observed are noted. Antenna patterns are provided for each application discussed.