Optimal Energy Cooperation Policy in Fusion Center-Based Sustainable Wireless Sensor Networks

In this paper, in order to maximize a long-term average system transmission rate, we propose an optimal energy cooperation policy for the sustainable wireless sensor networks where each pair of nodes can harvest energy and transfer energy in the pair. We formulate this optimization problem into a Markov decision process (MDP). We define a node pairing metric-relative energy distance ratio (REDR)-to design a node pairing algorithm which can decouple the original MDP into a multiple low dimension MDP. Then, value iteration and relative value iteration algorithms are brought to find optimal energy cooperation policies over finite and infinite horizons for each pair of nodes respectively. Simulation results show that the system transmission rate of the proposed policy with REDR based pairing algorithm outperforms the non-cooperation policies as well as the policies with straightforward pairing algorithms.