Research On Mobile Offloading Optimization Methods Based On UAV Assistance

With the rapid development of wireless communication technology,the ubiquitous wireless wide area network(WWAN)has brought great convenience to people’s lives.Users within the coverage of base station(BS)can access Internet resources and enjoy convenient services anytime,anywhere via WWAN,such as shopping,online games,etc.However,with the continuous increase of user equipments,the traditional static base station has been unable to meet the needs of users.Therefore,it has been proposed to solve the problem by assisting mobile users with Unmanned Aerial Vehicle(UAV)for computing offloading or data offloading.At present,most of the work focus on UAVs assisting users in computing offloading or data offloading.However,in some edge scenarios where infrastructure is extremely limited,there is no effective way to address both the computing and data offloading requirements.Therefore,we propose a model for UAVs to assist users in mobile offloading that including computation offloading and data offloading.The main work of the our paper are as follows:Firstly,for the problem of single UAV assisting users for mobile offloading,we establish a single UAV mobile offloading model.Then,we propose a two-stage iterative optimization algorithm to solve it.Under the premise of considering the fairness among users,the algorithm achieves the goal of high satisfaction of all users by jointly optimizing the energy management,power management,bandwidth allocation and trajectory of the UAV.Secondly,aiming at the problem that multi-UAVs cooperate with each other to help users to perform mobile offloading,we establish a multi-UAV mobile offloading model.Then,we propose a three-stage iterative optimization algorithm to solve it.The algorithm considers the fairness among users and the matching problem between UAVs and users while avoiding multi-UAV path conflicts.By jointly optimizing the UAV energy management,bandwidth allocation and multi-UAV trajectory,it achieves the goal of maximizing the minimum computation rate among all users.Finally,the model of the single UAV and multi-UAV assisted mobile offloading models are simulated,and the experimental results are analyzed and summarized.Firstly,we simulate the mobile offloading method of single UAV.The effectiveness of the proposed scheme and the convergence of the two-stage iterative optimization algorithm are verified by a largenumber of experiments.Experimental results show that it can greatly improve the users’ computation rate.Secondly,we simulate the multi-UAV assisted mobile offloading model and verifies the convergence of the proposed three-stage iterative optimization method.The experimental results show that the UAV paths obtained by the proposed scheme has better effect than other paths.Finally,by comparing the minimum computation rate of users with the help of multi-UAV and single UAV,it is verified that multi-UAVs can assist more users to perform mobile offloading than single UAV.