Calculating call blocking and utilization for communication satellites that use dynamic resource allocation

The performance of most satellite communication (SATCOM) systems is characterized by loading analyses that assess the percentage of users or total throughput a particular system can satisfy. These analyses usually assume a static allocation of resources in which users request communication resources 100% of the time and higher priority users often block lower priority users from getting service. However, the loading of more dynamic, circuit networks such as the public-switched telephone network (PSTN) is typically analyzed on a statistical basis where the probability of a blocked call is computed. These types of systems can potentially satisfy more users than those that use static resource allocation because they take advantage of statistical multiplexing. As SATCOM moves toward a more dynamic concept of operations (CONOPS) to take advantage of potential statistical multiplexing gains, it is crucial to develop analysis capabilities to evaluate performance. In this paper, a method is developed to calculate call-blocking, preemption, and resource utilization for dynamically-allocated SATCOM systems in which users have different priorities and bandwidth requirements. The first part of the study augments the classical M/M/m queuing model to account for users with different priorities and bandwidth requirements. In the second part of the study, the model is used to predict the performance for two competing traffic classes with different bandwidths or priorities and highlight important trends. Finally, the third part of the study directly compares the performance of static and dynamic resource allocation approaches. This work was performed by The Aerospace Corporation in collaboration with a team of students representing the Research in Industrial Projects for Students (RIPS) Program. Administered by the UCLA Institute for Pure & Applied Mathematics (IPAM), RIPS provides opportunities for high-achieving undergraduate students to work in teams on real-world research projects proposed by a sponsor from industry.