认知无线网络中动态频谱接入性能分析

认知无线电技术利用频谱空洞进行通信,有效缓解了频谱资源紧缺问题,动态频谱接入是其核心技术。网络中主用户对授权频谱的使用效率较高时,次用户接入网络无法完成符合QoS要求的通信,只有当主用户频谱效率在一定门限值下时网络才适合次用户接入。有限频谱空洞资源只能满足有限次用户的通信需求,为了保证通信质量,网络在固定的主用户频谱效率下只能接入适量的次用户。提出用强制优先排队理论对认知无线网络中的动态频谱接入过程进行模拟,通过仿真对次用户的切换概率、阻塞概率两个QoS因子进行分析,在给定的QoS条件下,得到了网络适合次用户接入的主用户频谱效率门限值,以及在固定的主用户频谱效率下网络适合接入次用户的量。

Performance analysis of dynamic spectrum access in cognitive radio networks

Cognitive radio technology use spectrum hole to communicate can effectively solve the spectrum shortage problem, dynamic spectrum access is its core technology.When primary users' spectral efficiency is high in the network,second user can not complete the commuication under the QoS requirements, second users should not access the network.Finite spectrum hole resources can only meet the demand of finite second users,in order to ensure communication quality,network can only access the appropriate amount of second users under a fixed primary users' efficiency. This paper modeled the process of dynamic spectrum access in cognitive radio networks with a mandatory priority queuing theory,analysed second users' handoff probabaility and blocking probability,the condition of second users access network and how many seond users could be accessed under a fixed primary users' efficiency could be obtained from the simulation results.