认知无线电中接入机会的建模与优化  

Modeling and optimization of access opportunity in cognitive radio

作　　者：韩维佳[1] 李建东[1] 姚俊良[1] 李赞[1] 

机构地区：[1]西安电子科技大学综合业务网理论及关键技术国家重点实验室,陕西西安710071

出　　处：《西安电子科技大学学报》2012年第1期1-6,共6页Journal of Xidian University

基　　金：国家杰出青年科学基金资助项目(60725105);973计划资助课题(2009CB320404);长江学者和创新团队发展计划资助项目(IRT0852);863计划课题;国家自然科学基金资助项目(60902032);国家重点实验室专项基金资助项目(ISN02080001);高等学校创新引智计划资助项目(B08038);教育部科学技术研究重点资助项目(107103;K50510010022);国家新一代宽带无线移动通信网科技重大专项资助项目(2010ZX03006-002-04)

摘　　要：针对认知无线电系统中次级用户的感知接入问题,提出了一种频谱感知与接入机会联合建模的优化方法.该方法考虑了频谱感知对次级用户接入机会的影响,并分析了用户间分布对次级用户接入机会的作用,使次级用户系统能够根据不同的应用场景工作在最佳状态.而目前现有的相关工作忽视主次用户之间在空间分布上的关系,使理论分析不能够匹配实际问题.仿真结果验证了联合建模方法能够匹配实际情况,利用此方法设置次级用户系统可以使其频谱利用效率最高.This paper proposes jointly optimizing the access opportunity and spectrum sensing to achieve the maximum efficiency of spectrum utilization for the secondary user. In cognitive radio, the opportunistic access interwinded with spectrum sensing plays a key role in determining the performance of the secondary system. However, current related research neglects the relationship between primary user and secondary user in the spatial domain, which leads to incorrect evalution of the quantity of available access opportunity for the secondary user. To deal with this problem, a closed-form function is derived to Calculate the secondary medium access probability with regard to the impact of spectrum sensing and user spatial distribution. By using this derived closed-form function, the secondary user can obtain the optimum sensing configuration to ensure the efficient spectrum utilization of the secondary system. Simulation results show the correctness of the closed-form function and the efficiency of the related optimization.

关 键 词：认知无线电 频谱感知 机会接入 

分 类 号：TN915.02[电子电信—通信与信息系统]