Research On Relay Average Throughput Optimization And Fast Deployment After Disaster In UAV Communication

Unmanned aerial vehicle(UAV)communication is an important part of the next generation communication(5G),and it is also a communication technology with significant advantages and challenges.Due to its inherent properties,such as flexible mobility,better channel conditions and adaptive deployment,they are more and more widely used in civil and military fields.Compared with the traditional relay,the use of UAV as aerial relay has greater advantages.In the military field,UAV used as aerial relay can expand the radius of military information feedback.Real-time grasp of enemy intelligence,so as to be in a favorable position in combat.In the civil field,the use of UAV as aerial relay can not be ignored.In the case of natural disasters,such as forest fires,earthquakes and so on,before natural disasters occur,the ground communication infrastructure works well.However,after the occurrence of danger,the communication facilities in these places are usually severely damaged,resulting in the equipment can not communicate with each other.Therefore,providing emergency communication has become the most urgent requirement.We use UAV as aerial relay to solve this problem.When UAV is used as aerial base station,it can improve network coverage,capacity and link reliability.For example,in traditional cellular networks,the use of UAVs as aerial base stations can provide better communication services for hot spots in cellular networks and increases system capacity.However,there are few studies on fast deployment of UAV in the literature.This paper considers UAV relay network model and fast deployment scenario after disaster.In UAV relay network,a non-convex optimization problem with average throughput as the objective function is established,and in post-disaster fast deployment scenario,an optimization problem is proposed and we use deployment completion time as the objective function.The main work is as follows:1.The UAV relay network model is studied in this paper.Because of the blockage of high buildings,the ground source node can not send the signal to the destination directly.The UAV is used as an aerial relay to assist the transmission.The problem of maximize link average throughput of UAV with circular and linear trajectories is analyzed.The flight speed limitation of UAV,the total power limitation in the network and link performance(outage probability)are considered in the optimization problem.Since the original problem is a non-convex optimizationproblem,we decompose the original problem into two independent sub-problems and solved they by corresponding methods.2.Considering the non-convex optimization problem in UAV relay network,the power allocation method and convex optimization technology are mainly used in wireless communication field.Reasonable power allocation can make better use of power resources and improve system performance.Convex optimization technology can optimize the objective function by optimizing parameters under certain constraints.The experimental results show that the minimum outage probability can be obtained by using the adaptive power allocation method,and the system performance achieves the best.3.The fast deployment of UAV after disaster is studied.A non-convex optimization problem is established by taking UAV completion time as the objective function,and a novel algorithm is proposed to solve the optimization problem.Compared with the random deployment of UAV,deployment time is shorter in the proposed algorithm.