Research On Power Control Algorithm Of Cognitive Vehicle Network Based On Non-cooperative Game Theory

The Vehicular Ad-hoc Network is an innovation in the application of wireless communication.It is expected to improve road safety and vehicle traffic efficiency through the development of intelligent transportation system(ITS).Therefore,it has gradually become the focus of the current research on the development of intelligent transportation.In addition,the transmission performance of communication data between vehicles is greatly reduced for the limited,scarce and low utilization of spectrum resources.In order to solve the above problems,cognitive radio enabled vehicular ad hoc networks(CR VANETs)quietly appeared.In CR VANETs system,the transmission power can be controlled to improve the system utility,alleviate the low spectrum utilization in large part,and improve the throughput.Thus,reasonable power control scheme is very important to the above problem.At present,experts at home and abroad have solved the power control problem of single objective and simple communication environment by combining swarm intelligence optimization algorithm,deep learning,machine learning and other methods.However,when the changeable topology is complex and multiple objectives coexist,the above theory is relatively single and can not achieve good results.In view of the above problems,the game theory is introduced into the power control problem of cognitive vehicle network in this paper,which transforms the competition problem between cognitive vehicles into a game problem.And the relevant power control algorithm is proposed to achieve good results.The main research work of this paper is as follows:1)In this paper,the mathematical model of minimizing the transmission power of all cognitive vehicles is established in the cognitive vehicle networking system,which meets the constraints of transmission power,minimum signal-to-noise ratio and system interference at the same time.Combined with the traditional K-G algorithm,a power control algorithm GT1 algorithm is proposed based on the average interference temperature.And the existence and uniqueness of the algorithm are proved.In the algorithm,the service quality of each vehicle is ensured,the law of linear punishment of selfish vehicles is broke based on the average interference temperature by traditional algorithms,and considering the problem of different interference is caused by vehicles at different distances.The simulation results show that the proposed algorithm effectively reduces the transmission power of the vehicle on the premise of ensuring the normal data transmission of the vehicle.And the convergence speed of the algorithm is fast.2)Based on the above algorithm,a power control algorithm GT2 algorithm with weighted interference temperature value is proposed to aim at the problem of different vehicle distances in GT1 algorithm.The punishment mechanism is optimized,the weighting coefficient is added,and different punishment schemes are adopted for vehicles with different distances.The simulation results show that GT2 algorithm has a better power control scheme than that of K-G algorithm,Balance algorithm,GT1 algorithm,which can further eliminate the problem of "near far effect" between vehicles,greatly improve the fairness of vehicles,reduce energy consumption and optimize the overall network structure of the system.