COST PER BILLABLE MINUTE METRIC FOR COMPARING SATELLITE SYSTEMS

The cost per billable minute is the metric to compare the efficiency o f different mobile satellite system architectures. The cost per billab le minute to achieve a specified rate of return is determined from est imates of the useful system capacity and life cycle costs, To evaluate the useful system capacity, a computer simulation was developed to mo del the complex interaction between satellites, gateways, capacity lim its, and an expected market model. The major capacity limiting factors addressed include frequency reuse, constellation design, link availab ility, spotbeam patterns, multiple access schemes, and satellite power , The life cycle costs were estimated for the satellites, launch vehic les, gateways, public switched telephone network hardware connections, operations, and launch insurance, The metric is evaluated for six mod el systems in low, medium, and geostationary Earth orbits to demonstra te the usefulness of the metric in the design process.