The research background of the Telstar experiment

For several years before the launch of the Telstar satellite, research effort was directed toward an experiment with an active satellite capable of relaying a broadband communication channel. The intention was to utilize and test a number of novel techniques which had become available, to explore those areas in which the current technology was lacking, and to demonstrate the feasibility of this means of communication. This paper describes some of this work, the background of facts and beliefs on the basis of which a number of important choices were made, and the general state of the radio art upon which the Telstar program was built.