RF Energy Source Deployment Schemes With Given Candidate Locations In Wireless Powered Networks

In traditional wireless sensor networks,the nodes are powered by batteries and have very limited energy.Nodes usually placed in harsh environments,once the battery capacity is exhausted,it is generally difficult or impossible to charge or replace the battery.Energy harvesting,as an emerging technology,brings the gospel to traditional wireless sensor networks.Nodes can perform battery life by capturing the energy of the environment,such as solar energy and kinetic energy,to supplement the node's energy consumption.Among them,battery charging by capturing radio frequency signal energy in space is a very promising energy capture solution.This paper considers radio frequency energy harvesting wireless sensor networks(RFEH-WSNs)powered by radio frequency energy sources(ESs).The characteristics of the RF energy capture sensor network,in the downlink,the node can collect the energy signal of the RF energy supply source for its own signal transmission requirements.Then in the uplink information transmission,the node access point collects the data signals sent by the node.Obviously,the greater the energy capture power of a node,the more energy a node has to perform operations such as sensing and sending data.There are many factors that affect the energy capture power of a node,such as the number of energy sources,the location of the energy sources,the RF source energy transmission power,and the transmission scheme used.Among them,the location deployment of the energy source will greatly affect the capture efficiency of each node.This is because the wireless signal weakens sharply as the transmission distance increases.The distance between the node and the energy source greatly affects the energy of the nodes in the network.Capture rate.In addition,the optimization of the transmit power of the energy source is also an important aspect,because under the premise that the energy capture power requirements of the nodes are also met,an unreasonable transmit power setting will cause a larger total transmit power,which will cause a larger energy consumption.Therefore,this paper intends to study the placement of energy sources in the case of a given location of energy source candidates.Most of the existing research work considers scenarios where no candidate location is given.However,in practical application scenarios,there are often many areas where energy sources cannot be arranged.Energy sources can only be arranged in some reasonable candidate locations.This paper considers three newer energy source placement issues for a given candidate placement location.The main research contents of this article are as follows:(1)Knowing the node position,the number of ESs,and the candidate placement position of ESs,research and design an ES placement scheme that maximizes the total energy capture power of the node.This problem is first modeled as a 0-1 integer programming problem,then an approximation algorithm with an approximate ratio of(1-1/e)with lower complexity and a based on Genetic algorithm placement algorithm.(2)Research and design the ES layout and transmission power setting scheme to minimize the total energy supply of ESs.This problem is first modeled as a mixed integer programming problem;then a heuristic algorithm with lower complexity and a genetic algorithm based on combined linear programming that can achieve a smaller total energy supply are proposed respectively.(3)The research designed the minimum ESs scheme on the premise of the smallest total power consumption of the network to model the problem as an optimization problem in order to understand the essence of the problem.Then,a low complexity deployment algorithm based on greedy algorithm and a slightly more complex deployment algorithm based on genetic algorithm are proposed.