Network throughput maximization in unreliable sensor networks with a mobile sink

In this paper we consider a sensor network with unreliable wireless links, a pre-defined path in the monitoring region, and a mobile sink traveling along the path. The sink departs from a depot, chooses some anchor points on the path to stop for data collection, and finally returns to the depot after a given monitoring duration. The per-tour traveling distance of the sink is bounded by a specified length. The trajectory of the sink consists a sequence of the chosen anchor points and the same anchor point may appear multiple times. We aim to find a trajectory and the sojourn time scheduling at each anchor point in the trajectory for the mobile sink such that the network throughput is maximized while the constraints imposed on the sink mobility are met. We first formulate the problem as a novel mobility constrained network throughput maximization problem. We then propose two practical heuristics for the problem. To evaluate the performance of the heuristics, we find the optimal solution and use it as a benchmark for the heuristics. We finally conduct experiment by simulations to validate the effectiveness of the proposed heuristics and show that their performance is fractional to the optimum.