An Energy-Balanced Joint Routing and Charging Framework in Wireless Rechargeable Sensor Networks for Mobile Multimedia

In wireless rechargeable sensor networks for mobile multimedia services, the multi-hop transmission method is often used to reduce the distance of a single hop to save energy. However, the sensor nodes in special locations always carry more forwarding load,which causes energy holes. These sensor nodes in energy hole have the higher energy consumption and the less residual energy, which makes them very fragile and easy to exhaust energy. If a sensor node dies, the structure of the network will be changed and the original function will be affected. In this paper, an energy-balanced joint routing and charging framework is proposed to balance the energy consumption between sensors. By analyzing the network model, the proposed framework is decomposed into a routing strategy and a charging strategy. Considering the impact of the routing structure on sensors energy consumption, the goal of the routing strategy is designed to optimize the routing tree corresponding to the mobile charger staying at each sensor node. Furthermore, the proposed charging strategy prefers the charging path with the best balance of the total energy consumption of sensor nodes during one charging trip. In order to solve these optimization problems, the simulated annealing algorithms, including the proposed random solution generation method and acceptance rules, are used to obtain a fast convergence. The simulation results show that the proposed joint routing and charging framework has better energy balance performance than the traditional scheme.