Optimal transmission period for improved sink-based data collection in energy harvesting wireless sensor networks

In this paper, we focus on the issue of maximizing the data collected by a mobile sink with unlimited energy which traverses a given straight path in an energy harvesting wireless sensor network (EH-WSN). Sensors are assumed to harvest energy periodically from the solar resources in their surrounding. Due to limitations on energy replenished within different time intervals, the sensors can reduce their transmission period in time slots with lesser available data in order to conserve energy for the possibility of higher data transmission in consecutive slots. Aiming at improving the overall network throughput, we formulate the problem of finding the effective data transmission period as a mixed integer linear programming (MILP) optimization model. With prior knowledge of the maximum transmission range, we design an online centralized algorithm for the problem which is run by the sink and easily scalable to large network sizes. Corroborated by extensive simulation results, we demonstrate that the proposed algorithm outperforms the existing work with the mean of throughput improvement being inversely proportional to that of the energy harvested while exhibiting the same order of computational complexity.