Optimal time slot allocation for multiuser wireless networks

Resource management in wireless networks is an important issue because of the scarceness of communication resource. So optimization schemes for efficient resource usage have been extensively researched. Throughput maximization under the condition of limited total power or power minimization under the condition of minimum bit rate are usually considered objective in many papers. These researches focused on the power allocation, but they did not consider time slot allocation which can be also used to improve the efficiency. In this paper, we introduce a time slot allocation problem for multiuser wireless networks to achieve minimum rate guarantee under the condition of fixed total power. We solve the allocation problem by using dynamic programming method, which has the complexity of O(K³) where K is the number of users. This complexity is lower than the nonpolynomial complexity of exhaustive searching for the optimal solution. The performance of our proposed algorithm is compared with that of the water-filling algorithm. An advantage of using the time slot optimization approach is that it can support high mobility users with QoS requirements. From simulation results, we demonstrate that our proposed algorithm shows better performance than a conventional scheme that does not use any time slot allocation.