Adaptive path scheduling for mobile element to prolong the lifetime of wireless sensor networks

Mobile elements, which can traverse the deployment area and convey the observed data from static sensor nodes to a base station, has been introduced for energy efficient data collection in wireless sensor networks (WSNs). However, most existing solutions only calculate a single path for the mobile element, which may lead to quick energy depletion for sensor nodes that are far away from the path. In this paper, for real-time data collection in a WSN with one mobile element, we study the adaptive path scheduling problem for prolonging the lifetime of the WSN. Here, multiple paths are planned and the mobile element follows the paths in turn to balance the energy consumption on individual sensor nodes, thus to extend the WSN's lifetime. We first illustrate the problem with one motivational example. Then, for cases where the movement of the mobile element is restricted (e.g., straight lines), we propose and analyze the optimal solutions. For the general cases, we discuss the issues involved and speculate our future research directions.