SCHEDULING WITH ASYNCHRONOUS SERVICE OPPORTUNITIES WITH APPLICATIONS TO MULTIPLE SATELLITE SYSTEMS

A single server is assigned to M parallel queues with independent Pois son arrivals. Service times are constant, but the server has the oppor tunity to initiate service at a given queue only at times forming a Po isson process. Four related scheduling policies are investigated. a) A simple first-come, first-serve policy for which the stability region is determined, b) A policy with maximum throughput, but requiring the server to have advance knowledge of service opportunities, c) A policy of threshold type, which is shown to be optimal among nonlookahead po licies with preemption, and d) An adaptive policy, which when M = 2 is shown to provide stability for all arrival rate vectors for which sta bility is possible under any nonlookahead policy with preemption. The work is motivated by the problem of transmission scheduling for a pack et-switched, low-altitude, multiple satellite system.