passive communications satellite การใช้

"' Project Echo "'was the first passive communications satellite experiment.
Later passive communications satellites such as OV1-08 PasComSat solved the problems associated with this by using a grid-sphere design instead of a covered surface.
Echo 1 ( seeEcho satellite ) was a plastic mylar balloon put in space as a passive communication satellite in 1960 which lasted until 1968.100 feet across, it was easily seen with the naked eye when in the right portion of the night sky to reflect sunlight.
The horn antenna at Bell Telephone Laboratories in Holmdel, New Jersey, was constructed in 1959 to support Project Echo & mdash; the National Aeronautics and Space Administration's passive communications satellites, which used large Earth orbiting aluminized plastic balloons as reflectors to bounce radio signals from one point on the Earth to another.