American telecommunication program operated by NASA.
Some TDRS satallites have got a so called commercial payload, operated by Columbia Communications
(C-band). Provides communications, tracking, telemetry, data acquisition and
command services essential to Shuttle and low-Earth orbital spacecraft
missions. The TDRS system can provide communications services to orbital
spacecraft over 85 percent of each orbit for most satellites, and continuous
service for some orbital positions.
The TDRS system was initiated following studies in the early 1970s which showed
that a system of telecommunications satellites, operated from a single ground
station, could meet the needs of NASA's mission better and more
cost-effectively than the then existing network of tracking and communications
ground stations located around the world.
