On the mixed support of TDMA and SCPC for satellite disaster communications network

This paper presents basic considerations on the mixed support of TDMA (Time Division Multiple Access) and SCPC (Single Channel Per Carrier) transmission for satellite disaster communications network. Since each of TDMA and SCPC transmission has its own advantages in efficiency and flexibility according to the network characteristics, integral use of them could lead to the improvements in bandwidth utilization. We categorize the formation of bandwidth assignment into four scenarios and describes the characteristics of each scenario. First two scenarios are somewhat dedicated configurations of TDMA and SCPC in which each scheme occupies certain amount of bandwidth exclusively at least for a time period. Next two scenarios are totally integrated approaches that TDMA and SCPC traffic shares entire bandwidth by DAMA (Demand Assignment Multiple Access) mechanism. This category seems to provide better adaptability to the network variations yielding better efficient utilizations. No one of the scenarios has the best performance for every situation of network characteristics, and thus the trade-offs are carefully considered for the specific operational environment.