Relating to the efficiency of utilization of the geostationary orbit/spectrum in the fixed-satellite service

Rapidly growing radio-telecommunications needs, only partially satisfiable by the use of new frequency bands, demand greater, more efficient, use of traditional frequency bands. The development of geostationary fixed-satetlite communications systems is a prime example of the pressures towards more efficient spectrum utilization. It is investigated in which manner the geostationary orbital spectrum may be utilized to produce more capacity. The major means to achieve this derive from 1) technical factors which affect the frequency reuse potential of the geostationary satellite orbit; 2) technical factors which affect the amount of information which may be transmitted in a given bandwidth; and 3) other factors which facilitate or enhance the application of the technical factors with a view towards conserving and increasing orbit and spectrum utilization. Each of the individual factors is discussed in some detail, and estimates of their impact on orbit/spectrum utilization efficiency are provided in parametric form.