Study On Effective Placement Algorithm For Energy Transmitter In RF Energy Harvesting Wireless Sensor Networks

The life cycle of wireless sensor networks(WSNs)is often limited by the limited battery power.In order to improve the life cycle of the network,researchers put forward a variety of network protocols,or further put forward to draw solar energy,wind energy from the environment,etc.,to extend the life time of the network.But these methods are generally restricted by environmental factors and can not be promoted.RF energy harvesting wireless sensor network(RFEH-WSN)consists of dedicated energy transmitter(ET)and sensor nodes with RF energy harvesting technology.The function of the RFEH-WSN is to solve the problems of limited battery capacity in the sensor networks.How to place ET effectively with minimum energy consumption and maximize overall charging utility is one fundamental issue in RFEH-WSN.In this paper,the optimal layout strategy of ET's residence position is studied.Firstly,the problem is modeled.The single objective optimization model with the minimum time is proposed,and the method of combining particle swarm optimization and linear programming is proposed to solve the minimum charging time and obtain the optimal charging position.The multi-objective optimization model with the minimum time and the maximum coverage is established,and the particle swarm optimization algorithm is proposed Swarm optimization(PSO)is a low complexity approximation algorithm for solving multiple object program(MOP).The optimal Pareto solution set is obtained.The simulation results show that multi-objective optimization can solve the conflict between time and coverage,and multiple different optimal solutions can be selected to meet the charging needs of different scenarios.The algorithm effectively improves the charging utility.