Sweeping and active skipping in wireless sensor networks with mobile elements

Using mobile elements (MEs) as mechanical carriers to collect data brings many opportunities to wireless sensor networks, such as improving the energy efficiency of sensor nodes and prolonging network lifetime. However, the limited travel speed of MEs leads to a higher data transfer latency, which in turn degrades the performance of the data collection task. The optimal use of the limited mobility of MEs is thus critical to the overall performance optimization. Considering the data-rate constraints of wireless communications, and by following a progressive optimization approach, we propose a sweeping tour optimization scheme with active skipping (SAS) in this paper. The performance of the proposed scheme is evaluated by investigating the tour length and the data collection latency. Through extensive simulations, our scheme is shown to outperform the best known heuristic algorithms in terms of the data collection latency.