Frequency sharing between the broadcasting-satellite service and other radiocommunication services

When frequency requirements for space radiocommunications were first considered, the radio frequency spectrum was already fully allocated. Thus, from the very first ITU conference dealing with allocations for space services in 1959, the space services have had to share bands with one or more terrestrial services and, more recently, with other space services. The broadcasting-satellite service (BSS), which is considered in this paper, is also affected by this situation. Primary attention is given to the use of the same band by different services in the same and different Regions. Some consideration is also given to the use of BSS bands by stations of the BSS in the same and other Regions. Aspects of downlink sharing are discussed along with questions of feeder link sharing, and existing problems and required future action.