Optimal Time Dependent Data Collection Schemes in Wireless Sensor Networks

In this paper, we investigate two relaxed versions of the time dependent (delay-constrained) data collection problem in wireless sensor networks, namely: (i) data collection with minimal delay; and (ii) maximising the number of collected data with a given delay-constraint. Furthermore, these problems are studied in networks with rechargeable nodes, and lossy radio links, due to signal interference and channel fading. In this paper, we propose two decentralised algorithms to solve these problems, which, under certain assumptions, are optimal, in terms of achieving minimal delay, and maximal collected data, respectively. We prove that these algorithms have polynomial complexity. By using extensive simulations, we demonstrate that both algorithms have low communication overhead on average.