Research On Mobile Charging Optimization Method In Wireless Sensor Network

The common working method in traditional wireless sensor nodes is to maintain the work by equipping the node with a battery,which is limited to the battery capacity and battery output power.The sensor network has a limited life and the traditional charging method has a low charging efficiency.Other wireless charging technologies that can improve the charging efficiency more reasonably and effectively.The current charging models in wireless sensor networks can be divided into single-node charging and multi-node charging models according to the number of charging targets.The multi-node model can be divided into omnidirectional wireless charging models and directional wireless charging models according to its coverage.And hybrid charging using a combination of two charging methods of solar panels and the mobile wireless charging vehicle.This paper focuses on the directional wireless charging models and hybrid charging models,proposes corresponding mobile scheduling optimization methods.The remainder of this paper is structed as follows:(1)The mobile charging optimization scheduling strategy based on the single-to-many directional wireless charging model is researched.The optimization goal is to maximize the cumulative charging gain of the wireless sensor network.To solve and optimize this problem,this paper first defines the cumulative charging gain of the sensor in directional wireless charging,and converts the docking spots and charging direction selection of wireless charging vehicle in a two-dimensional plane into a dual-objective problem that minimizes the number of stops and maximizes the sum of the cumulative charging gain.Secondly,this paper proves that the optimization problem is an NP-hard problem and proposes a corresponding approximation algorithm.Specifically,calculating the charging cycle and proving that no node would stop working due to energy exhaustion during the cycle.Then,the theoretical analysis shows the network scale of a single wireless charging vehicle can service.Finally,the effectiveness of the proposed algorithm is proved by simulation experiments.(2)The mobile wireless charging scheduling optimization scheme based on the hybrid charging model is researched.The optimization goal is to maximize the charging amount per unit trip of the wireless charging vehicle.This paper addresses two issues.The first problem is the placement of solar panels,and it proves that this problem is an NP-hard problem.The second problem is to determine the path of the wireless charging vehicle.To solve the problem,two corresponding algorithms are proposed in this paper.The first algorithm is a solar panel position selection algorithm.This algorithm determines every wireless sensor node in the network as an alternative position for the solar panel,and then the goal is to minimize the sum of network routing consumption and the cost of placing the solar panel to determine the place and number of solar panels.The second algorithm is a comprehensive weight comparison algorithm that converts the remaining power of the wireless sensor node and the distance of the wireless charging vehicle into a comprehensive weight and arranges the charging queue,and schedules the mobile charging vehicle's charging path to maximize the unit travel charge of the wireless charging vehicle.