Abstract :
The paper deals with the practical aspects of the evolution of a space communication system from the initial design concept to the performance in orbit. Selected design problems encountered during the design and test phases of several space communication systems are discussed along with the remedial action taken to correct unforeseen deficiencies. The telemetry, tracking and command system used to collect the data from Pioneer I, Explorer VI and Pioneer V are used in the paper as examples of system evolution. The paper is concluded with a brief discussion of current work to improve the efficiency and reliability of space communication systems.