A Model of a Domestic Satellite Communication System

Domestic satellite systems can be expected to handle a large amount of traffic compared with that carried by transoceanic systems; this is true even if for various reasons only a fraction of the total domestic traffic goes via satellite. For this reason among others, the presently allocated frequency bands at 4 and 6 GHz are not well suited to domestic use. Frequencies above 10 GHz are attractive in that they are not as heavily loaded as the lower frequency bands. But they are subject to propagation difficulties which generate new problems in their use.* The amount of atmosphere traversed by a ground-to-satellite path can be relatively small if the look angle is restricted to elevations which are not too small. However, attenuation will be large under conditions of excessive rainfall and diverse ground terminals will * Similar arguments apply to terrestrial systems operating above 10 G H z . These are not discussed here, b u t some of the propagation studies described here were designed with the needs of terrestrial as well as satellite systems in mind. 2111