TDMA-Based Time Slots assignment Algorithm

摘要

In this paper we studied timeliness of TDMA-based MAC scheduling mechanisms. TDMA-based MAC protocols require sensor nodes to deliver data individually so as to eliminate collisions in shared channel. This scheduling mechanism can assist sensor nodes in managing energy efficiently since data resending that collisions induced has a significant impact on battery life. But during medium access arbitration, the elected central node has to receive other nodes' state messages one by one before assigning time slots for each node. While in large-scale sensor networks, the waiting time would be a relatively long duration and result in timeliness decrease in time-sensitive environments. We propose a novel time slots assignment algorithm for TDMA-based MAC protocols that allows sensor nodes to deliver state messages simultaneously to central node for medium access arbitration and present an analysis in which these two approaches are compared in respect to timeliness. The algorithm is evaluated through simulation. Simulation results have confirmed the timeliness of our new algorithm.