Research On Key Technologies Of Power Allocation For UAV Communication System

In recent years,with the mass production of UAVs and the development of wireless communication technologies,UAV communication technology has become a research hotspot of current wireless communication technology,especially in the field of disaster relief and military.Special consideration is given to the fact that in the actual situation where ground traffic is blocked,the UAV can realize the obstacle communication and quickly establish an air platform to meet the timely communication requirements.However,due to the small size of the UAV and the limited power carried by the unmanned electromechanical board,how to minimize the power loss of the UAV while meeting the communication requirements has become an important research direction.This paper considers the application of UAV in relay network and the application of UAV in wireless sensor network,and improves the performance of UAV communication system through power allocation optimization algorithm.The main research contents and innovations of this paper are as follows:Firstly,considering the application of a single antenna-equipped UAV in a relay network,this paper proposes a joint optimization scheme for user scheduling and power allocation,aiming at maximizing wireless under the premise of limited total power of the UAV.The total channel capacity of the two-hop channel from the user terminal node to the UAV node and the UAV node to the control center node and the user with the best channel state selection by the user scheduling algorithm.The simulation result shows that under the given total power constraints,the channel capacity transmitted under the power allocation scheme proposed in this paper is significantly larger than the channel capacity transmitted under the traditional average power allocation algorithm.Secondly,the application of UAV with single antenna in wireless sensor networks is studied,considering the defects of the fixed information collector,this paper uses the mobile UAV as the information collector to collect the information transmitted by the ground sensor.Under the premise of limited information transmission rate from each sensor to the UAV,this paper use water filling algorithm and Lagrange multiplier method to minimize total transmission power.The simulation results show that under the premise that the information transmission rate of the communication link between each ground sensor and the UAV is limited,the power allocation algorithm proposed in this paper consumes less total power than the traditional equal power allocation algorithm and can improve the performance of the system.Finally,the application of multi-antenna UAV in relay network is explored,this paper discusses the power allocation optimization algorithm for multi-antenna UAV relay network under the condition of ignoring channel estimation error and existing channel estimation.In this model,the source transmits data information with a certain transmission power,and the UAV acts as a relay node and carries multiple transmission antennas,eventually reaching the destination node.Under the premise that the total power of two links is limited,this paper first considers the power resource allocation algorithm in the scene of ignoring the channel estimation error,and the channel capacity is maximized by this algorithm.On this basis,considering the channel estimation error between the actual channel characteristics and the estimated channel characteristics,this paper distributes the power of between two links in the presence of channel estimation error.The simulation results show that compared with the traditional average power allocation method,the power allocation method proposed in this paper can significantly improve the transmission capacity of the UAV in both two scenarios.