Research On Data Transmission For UAV-Aided Wireless Sensor Networks

Based on the vision of 6G to establish air-space-ground-sea integration and the advantages of Unmanned Aerial Vehicle(UAV)with high mobility,easy deployment and high probability of establishing line-of-sight links,UAV is widely used in the field of auxiliary Wireless Sensor Network(WSN)communication to solve the problem of limited energy of sensor networks and the bottleneck of their energy limitation on the performance of wireless sensor networks.There is a wealth of research related to UAV-assisted wireless sensor network communication,but there is not enough research on multi-dimensional information processing such as UAV power,position coordinates,flight paths,and operating modes in UAV-assisted wireless sensor networks.In order to solve the above problems,this thesis studies the UAV-assisted wireless sensor network data transmission.The main contributions include the following three points:1)Interference mitigation and resource allocation based UAV latency minimizing research: In order to mitigate the line-of-sight(LOS)interference between UAV-assisted wireless sensor networks and ground links,improve the increasingly crowded spectrum utilization and further satisfy the requirements for UAV transmission delay in UAV-assisted wireless sensor network scenarios,a wireless sensor network based on UAV coverage is studied.An optimization problem for minimizing the transmission delay of UAV-assisted wireless sensor networks is planned by considering the mitigation of co-channel interference and the allocation of communication resources.The UAV-tosensor node channel model based on the line-of-sight communication link is firstly considered to mitigate co-channed interference through the delay-frequency shift algorithm,thus reducing the bit error rate to improve the communication quality of wireless sensor network;then the UAV-assisted wireless sensor network data transmission delay minimization is achieved by jointly optimizing the sensor node transmission power,UAV 3D deployment,and bandwidth allocation.Finally,the simulation results show that the proposed algorithm has the advantage of reducing the BER,and the proposed algorithm can obtain lower transmission delay compared with the three benchmark schemes of optimizing the sensor transmission power,UAV position,and communication bandwidth,respectively.2)UAV working modes selection based wireless sensor network data: In order to adapt to the ever-changing wireless environment,solve the problem of limited energy of UAV-based sensor network,and break the bottleneck problem of its energy limitation on the performance limitation of wireless sensor network,this thesis propose a wireless sensor network based on UAV coverage and propose the adjustment scheme of UAV working mode based on state transfer by considering the UAV throughput and energy consumption comprehensively.Specifically,the channel models of UAV to sensor users including line-of-sight and non-line-of-sight communication links are first considered,and the parameters of UAV coordinate in static mode and UAV working cycle in cruise mode are designed.Then,the optimal UAV throughput and energy consumption are then obtained by solving for the optimal UAV coordinates and duty cycle,and the Economic efficiency(ECE)maximization problem,which can characterize the UAV throughput and energy consumption,is planned.Finally,by maximizing economic efficiency,the purpose of adaptive adjustment of the UAV to the working mode is achieved.Simulation results show that,compared with the traditional methods,the proposed algorithm can achieve higher performance in terms of economic efficiency.3)UAV-assisted communication operating mode selection based on intelligent reflective surfaces:Due to the complex communication environment,the line-of-sight transmission of the air-ground networks may be obstructed,which seriously affects the communication quality.Reconfigurable Intelligent reflective surface(IRS)is a promising solution to improve the wireless environment through reconfigurable passive units.Based on this,a new intelligent reflective surface-assisted airground communication scenario is studied,and an intelligent reflective surface-assisted UAV working mode adjustment algorithm is proposed.Specifically,the channel models based on UAV-IRS channel and IRS-ground node are first considered,and parameters such as UAV operating period in static mode and cruise mode are designed.Then,the system throughput is maximized by optimizing the intelligent reflective surface phase shift,however,since the objectives of maximizing throughput as well as minimizing energy consumption are contradictory,based on this the UAV economic efficiency maximization problem is planned.Finally,by maximizing economic efficiency,the purpose of adapting the working mode of UAV-assisted communication based on smart reflective surfaces is achieved.Simulation results show that the proposed algorithm can obtain higher performance improvement in terms of economic efficiency compared to the conventional method.