From HF radio to unified S-band: An historical review of the development of communications in the space age

Abstract

In the early years of space exploration, recovery of telemetry and tracking data from stations located at great distances from the control centres proved to be a most difficult task. The primary method of long-distance communications at the time of the Sputnik-1 launch in October 1957 was HF-radio teletype. This paper will examine the situation as it existed in 1957 and will comment on the development of communications systems needed to support early space exploration, but especially the impact on the NASA manned space flight programme. The importance of communications satellites and the use of digital data transmission for telemetry tracking and command functions will be examined and the essential nature of these systems to the success of the first lunar landing will be discussed at some length.