Dependence of the Maximum Range of Tropospheric Scatter Communications on Antenna and Receiver Noise Temperatures

This paper describes the dependence of the maximum range of scatter communications on noise sources both internal and external to the communications system. The discussion centers around the relative contribution of the new low noise solid state amplifiers in extending the range of communications in the face of terrestrial and extraterrestrial (cosmic) noise sources. It is shown that the apparant antenna temperature constitutes the primary limitation in realizing the full advantages of the low noise solid state amplifiers currently of such great interest.