Dynamic Spectrum Allocation Scheme For Vehicular Network

Vehicular network is an emerging intelligent strategic industry integrating communication,automobile,transportation and other industries,used to deal with the increasing communication problems of massive transportation facilities and provide effective services for diversified three-dimensional transportation network.Spectrum resource management technology is an important means to allocate spectrum resources and improve spectrum utilization.The existing spectrum resource management technology has the problems of high computational complexity,low spectrum sharing efficiency and high communication cost,which seriously limits the development of vehicular networks.Dynamic spectrum allocation is studied to improve the spectrum efficiency of vehicular networks in this thesis.The research details and contributions are as shown below:(1)The distributed spectrum allocation model of vehicular networks is established to provide flexible spectrum allocation scheme for various users.In this model,the dynamic channel access is designed to ensure the user’s demand for timeliness and flexibility of communication;the spectrum sharing mechanism between authorized users and unauthorized users is designed to meet the needs of diversified communication services of vehicular networks.(2)Dynamic spectrum allocation scheme based on game theory is proposed to improve the utilization efficiency of spectrum resources.The scheme uses the advantage of non-cooperative game theory in dynamic spectrum resource allocation,and combines cognitive function to analyze the relationship between users’ own spectrum strategy and channel interference,so as to achieve efficient utilization of spectrum resources.Simulation results show that the spectrum efficiency of the scheme is improved by more than 80% in the fully distributed scenario,reaching the level of centralized scenario.(3)Fast convergence spectrum allocation scheme for vehicular networks is proposed to reduce the number of time slots required for the stability of spectrum allocation,and improve the stability and feasibility of the spectrum scheme in this thesis.The scheme can realize multi-step cognition through users’ single iterative calculation,which speeds up the process of mutual guidance and cognition between users,thereby improving the convergence speed of spectrum allocation system.Simulation results show that the proposed scheme reduces the number of time slots needed to achieve stability by 71% while ensuring spectrum efficiency.(4)Spectrum allocation scheme with communication priority of users is designed to realize spectrum sharing between authorized users and unauthorized users with low complexity algorithm.Based on the spectrum allocation scheme in Chapter 3,the scheme realizes the identification authorized users for unauthorized users by controlling the power of authorized users.Simulation results showed that the impact on authorized users is less than 3%,which not only meets the spectrum resource requirements of unauthorized users,but also ensures the communication quality of authorized users.Dynamic spectrum allocation scheme of vehicular networks studied in this thesis effectively improves the spectrum efficiency in the full-distributed and multidimensional communication scenario of vehicular networks,and provides a feasible solution for the management and utilization of the spectrum resources of vehicular networks.The scheme has the characteristics of high efficiency,dynamic,high adaptability and low complexity.