Research On Resource Allocation Method Of UAV Communication System For High-Reliable And Low-Latency Services

Ultra-Reliable and Low-Latency Communication(URLLC),as one of the three key scenarios of The Fifth Generation mobile communication system(5G),has received extensive attention from academia and industry in recent years.This scenario requires extremely high reliability and extremely low latency,which plays an important role in supporting applications such as virtual/augmented reality,autonomous driving,and telemedicine.At the same time,Unmanned Aerial Vehicles(UAV)has significant characteristics such as high mobility,strong line-of-sight,and easy deployment.Relying on UAVs as communication platform can provide users with better channel conditions and quality of service.Therefore,it is considered to be an effective solution to meet the extreme performance requirements of URLLC.However,UAV communication systems for URLLC face the following challenges.On the one hand,strong line-of-sight characteristics not only bring better channel conditions,but also easily introduce more interference,which makes it difficult to apply the existing two-dimensional deployment methods and resource allocation methods of terrestrial networks directly.On the other hand,the mobility of UAVs makes the resource allocation scheme for URLLC services more complicated,and it is necessary to jointly optimize wireless resources and UAV trajectories.In view of the above two challenges,the main work of this thesis is as follows:Firstly,aiming at the challenge that the existing two-dimensional deployment methods and resource allocation methods of terrestrial networks are not directly applicable,a joint optimization method of UAV deployment height and resource allocation based on the strong line-of-sight characteristics of the air-ground channel is proposed.By jointly optimizing the UAV deployment height and URLLC service transmission time,this method maximizes network availability under the premise of ensuring the bit error rate constraint.The simulation shows that compared with the comparison scheme,the network availability performance of the method proposed in this thesis is improved by two orders of magnitude.Secondly,aiming at the complex challenge of optimizing the resource allocation scheme caused by the mobility of UAV,a joint optimization method of low complexity transmission power,URLLC packet code length,and UAV three-dimensional trajectory is proposed.This method can minimize the bit error rate under the premise of ensuring the transmission delay constraint.The simulation results show that the resource allocation method proposed in this thesis can significantly reduce the bit error rate of the URLLC service of the UAV communication system.Aiming at the challenges of resource allocation in URLLC-oriented UAV communication system,this thesis proposes a joint optimization method of UAV deployment height and resource allocation for maximizing network availability,and a joint optimization method of wireless resource and UAV trajectory for minimizing bit error rate,respectively.It provides theoretical and technical support for the practical deployment of URLLCoriented UAV communication system.