Ground Antenna for Space Communication System

The accurate tracking and telemetering of space probes requires the use of very sensitive receiving equipment and large antennas. The TRAC(E) system developed by the Jet Propulsion Laboratory utilizes an 85-foot-diameter, equatorially mounted, parabolic reflector. The antenna, similar to those used for radio astronomy, is located near Goldstone Lake near Barstow, Calif. The mechanical and electrical characteristics of the antenna and its subsystems are discussed, and its performance and the way it was used in tracking the lunar probe Pioneer IV are described. Limitations imposed on the space communication system by the ground antenna are discussed, and possible methods of improvement are listed.