DBS platforms - A viable solution

Various design options for the basic direct broadcast satellite (DBS) system are discussed. The first generation spacecraft are constrained by time zone problems, noting that one unit is insufficient to provide direct TV to an entire continent. An 800 W traveling wave amplifier is sufficient for full coverage of the entire U.S., while 200 W amplifiers are capable of single channel broadcast to a quarter to a third of the U.S. land area. A total of 24-32 satellites costing a total of $3.2-4.8 billion is required to provide full U.S. coverage with first generation DBS systems. The Shuttle is described as the means to providing GEO DBS services at affordable costs. Four large platforms, weighing 5300 kg, could be placed in GEO by a Centaur transfer stage after launch into LEO on the Shuttle. Studies have shown that four platforms, each with a 40 channel capability, power generating capacity of 30 kW, and 100% eclipse capability, could provide coverage for the entire U.S. Beam-shaping techniques offer any desired illumination pattern. Details of the institutional barriers which must be satisfied before the $500 million spacecraft could be launched are outlined.