【摘要】 为了有效快速的寻找到频谱空洞并不对主用户造成干扰,频谱感知是认知无线电系统中具有重要意义的一环。而多用户协作感知可以进一步提高系统性能。本文关注认知无线电MAC层两种频谱感知机制主动感知和被动感知机制。在多用户协作的场景下,分析主用户活跃度对感知性能造成的影响。并提出了一种低复杂度的折衷接入延时和功率消耗的优化策略。通过理论分析和仿真结果可以看出,主动和被动感知机制下多用户协作感知可以有效的减小信道搜索时间,优化算法帮助动态地选取感知机制减小系统开销。更多还原

【Abstract】 Aimed at efficient and fast searching of spectrum opportunities,while avoiding interference to primary users,spectrum sensing play a significant role in cognitive radio system.Generally,multi-user cooperative sensing can enhance the performance of system.Hence,this paper is focus on the characteristics of two kinds of sensing mechanism such as proactive and reactive sensing policy in a multi-user cooperation situation,and analyzes the sensing performance over the activity level of primary users.We proposed a optimization strategy of making a tradeoff between access delay and sensing overhead.Through the theory analysis and simulation,multiuser cooperative sensing in proactive and reactive mechanisms also reduce the channel searching interval.更多还原