Optimal Mobility Patterns of Multiple Base Stations for Wireless Sensor Network Lifetime Maximization

The success of widespread deployment and associated research efforts on wireless sensor networks (WSNs) is undisputed. Yet, there is still a large uncharted territory for exploring and improving many aspects of WSNs. As one of the most crucial design goals of WSNs, network lifetime (NL) maximization is one such area. Although energy balancing in data relaying toward a static base station (BS) prolongs NL, some nodes usually suffer from, what is generally known as, the hot-spot problem. BS mobility has been proposed in the literature against the hot-spots to mitigate the suboptimal energy dissipation. BS mobility increases the sensor NL significantly in certain network configurations. Furthermore, utilization of multiple mobile BSs extends WSN lifetime even further when compared with the single BS case. However, optimal mobility patterns of multiple mobile BSs should be employed for achieving the maximum WSN lifetime possible. In this paper, we investigate the characteristics of the optimal mobility patterns for WSN lifetime maximization by employing three representative patterns (i.e., grid, random, and spiral). We develop a novel mixed integer programming framework to characterize NL under different mobility patterns for multiple mobile BSs.