基于HMM和平衡二叉树递归搜索的宽带频谱感知  

Broadband spectrum sensing based on HMM and balanced binary tree recursive search

作　　者：荆淑霞[1] 申同强[1] JING Shuxia;SHEN Tongqiang(School of Computer Science and Engineering,North China Institute of Aerospace Engineering,Langfang Hebei 065000,China)

机构地区：[1]北华航天工业学院计算机学院,河北廊坊065000

出　　处：《太赫兹科学与电子信息学报》2021年第6期1014-1019,1026,共7页Journal of Terahertz Science and Electronic Information Technology

基　　金：北华航天工业学院校级科研资助项目(KYPT–2016-06)。

摘　　要：为了使得二级或无许可证用户在给定宽带上获取空闲的子带以供使用,针对认知无线电中的宽带频谱感知技术进行研究,提出一种有效的宽带频谱感知算法。算法采用隐马尔可夫模型(HMM)对初级用户的动态行为进行建模,以克服目前宽带感知技术的局限性;其次,利用现有窄带感知技术,将感知频带划分为较小的频道,将其建模为一棵平衡二叉树,并对频谱孔洞进行递归搜索。如果检测到有孔洞在频率上相邻,则将它们合并成一个单一的频谱孔洞,使得认知二级用户的容量在整个频带上最大化。仿真实验结果表明,与现有宽带频谱感知方法相比,提出的宽带频谱感知算法具有更好的感知性能增益和更强的鲁棒性。In order to enable secondary or unlicensed users to obtain idle subbands on a given broadband for use,the broadband spectrum sensing technology in cognitive radio is discussed and an effective broadband spectrum sensing algorithm is proposed.The algorithm first uses Hidden Markov Model(HMM)to model the dynamic behavior of primary users to overcome the limitations of current broadband sensing technologies.Secondly,the proposed algorithm uses the existing narrowband sensing technology to divide the sensing spectrum band into smaller channels and model it as a balanced binary tree;then the spectrum holes are recursively searched.If any holes are detected to be adjacent in frequency,they are merged into a single spectrum hole for maximizing the capacity of cognitive secondary users over the entire frequency band.The simulation results show that compared with the existing broadband spectrum sensing methods,the proposed broadband spectrum sensing algorithm has better sensing performance gain and stronger robustness.

关 键 词：射频频谱 动态接入 认知无线电 宽带频谱感知 隐马尔可夫模型 二叉树 信噪比 

分 类 号：TN925[电子电信—通信与信息系统]