UAV-assisted Security Wireless Power Transfer Communication Network

Throughout the development of modern communication technology,the rate of communication network is getting higher and higher.At the same time,the problem of energy consumption of communication devices are becoming increasingly prominent.In order to solve the energy supply problem of communication devices,wireless power transmission technology has become the current research focus.In the traditional wireless power transmission network,the base station as the core of energy transmission is often unable to be deployed normally due to various factors.In the process of searching for an alternative solution to base stations,Unmanned Aerial Vehicle（UAV）has become a better solution due to its flexible deployment and other characteristics.However,UAV communication has always had communication security problems caused by broadcast characteristics,which is also one of the challenges faced by UAV communication.On the other hand,in today’s era of increasingly important communication security,Covert Communication（CC）has created a path different from traditional physical layer security by devoting to concealing legitimate communication.However,CC is largely limited by the transmission of legitimate devices.How to realize covert communication with larger transmitting power is also one of the important research directions at present.Based on the above research background,thesis mainly considers the research of UAV-assisted secure wireless communication energy supply in three different scenarios.All research scenarios consider the realization of CC while considering the energy supply of passive devices.First,the simplest single-legitimate device and single-hostile warden scenario is studied,and the UAV transmits jamming signals to interfere with the warden’s decision while providing energy for the legitimate device.In the research,thesis proposes a joint optimization algorithm for UAV flight trajectory and transmit power and legitimate device’s transmit power to maximize the throughput of the system.Due to the nonconvexity of the objective optimization problem,an iterative algorithm of Alternating Optimization combined with Successive Convex Approximation technique is proposed in thesis to ensure that the original problem converges to a local optimal solution,thus solving the non-convex problem.The simulation results show that the concealment performance of wireless communication can be improved by reasonably changing the trajectory of the UAV and the transmit power of the legitimate device while ensuring the energy supply.Then,the research scenario is expanded to multi-legitimate devices and multi-hostile wardens to fit the actual scenario.On the basis of the original,the resource allocation algorithm with the addition of the legitimate devices’ scheduling strategy and the wardens’ joint listening strategy is further studied.Finally,in order to further improves the concealment performance,multiple auxiliary interference nodes are added to the original scene.In the research,thesis proposes a joint optimization algorithm for UAV transmitting power and auxiliary interference nodes to maximize energy transmission and throughput,and proposes an iterative algorithm of alternating optimization combined with onedimensional search to obtain a local solution to the original problem.The simulation results show that the auxiliary jamming node can greatly improve the covertness and energy supply.