Adaptive Global Reclustering in MWSNs

Abstract

Energy conservation is crucial for clustered wireless sensor networks (WSNs) due to the bounded energy at sensor nodes. Energy conservation is achieved mainly through load balancing, which is realized with reclustering in frequent time intervals called rounds. Although in clustering the round duration is typically fixed throughout the network lifetime, the use of a dynamic round duration based on energy exhaustion at sensor nodes has also been proposed. Even though many attempts have been made to determine the round duration dynamically, all of them focus on WSNs. However, in mobile WSNs (MWSNs), apart from energy exhaustion, packet loss due to node mobility is also an important issue to be considered in the case of dynamic round duration. To investigate the problem of the calculation of the dynamic round duration in MWSNs, in this article, we evaluate the applicability of an existing recluster triggering scheme initially proposed for WSNs, which is adaptive to energy consumption at cluster heads (CHs). We also propose a new scheme, the lost ratio reclustering (LRRC), which provides adaptivity to the percentage of mobility-induced packet losses at each CH. Furthermore, the case of reclustering in fixed time intervals is also considered. Simulation results show the effectiveness of the LRRC scheme in increasing the packet delivery ratio (PDR) and reducing the clustering energy overhead.