Opportunistic best-relay node selection for cooperative transmission improvement over underlay cognitive radio networks  

作　　者：陈丹 纪红 李曦 

机构地区：[1]School of Information and Communication Engineering,Beijing University of Posts and Telecommunications

出　　处：《Journal of Harbin Institute of Technology(New Series)》2011年第6期16-21,共6页哈尔滨工业大学学报（英文版）

基　　金：Sponsored by the National Major Science&Technology Project(Grand No.2009ZX03002-014);the National Nature Science Foundation(Grant No.60832009);the Beijing Municipal Natural Science Foundation(Grand No.4102044);the National Natural Science Foundation for Distinguished Young Scholar(Grand No.61001115)

摘　　要：In cognitive radio (CR) relay networks,most previous work concentrates on maximizing physical layer quality of service (QoS),e.g.,spectral efficiency and achievable data rate,as relay selection criteria.However,the residual energy state of relay nodes is largely ignored,which has significant effects on the average network lifetime for those battery-limited wireless networks.In this paper,an opportunistic distributed best-relay node selection scheme is proposed for cooperative transmissions over underlay-paradigm based CR networks,and meanwhile guarantee that the primary link is provided with a minimum-rate for a certain percentage of time.The objective is to increase achievable data rate as well as prolong average network lifetime.Specifically,both the instantaneous channel state information (ICSI) and residual energy of candidate relay nodes are taken as weighted metric,and the relay node with the optimal weighted metric is selected as the best one.Simulation results are presented to demonstrate the effectiveness of the proposed scheme.In cognitive radio （CR） relay networks, most previous work concentrates on maximizing physical layer quality of service （QoS） , e.g. , spectral efficiency and achievable data rate, as relay selection criteria. However, the residual energy state of relay nodes is largely ignored, which has significant effects on the average network lifetime for those battery-limited wireless networks. In this paper, an opportunistic distributed best-re- lay node selection scheme is proposed for cooperative transmissions over underlay-paradigm based CR networks, and meanwhile guarantee that the primary link is provided with a minimum-rate for a certain percentage of time. The objective is to increase achievable data rate as well as prolong average network lifetime. Specifically, both the instantaneous channel state information （ICSI） and residual energy of candidate relay nodes are taken as weighted metric, and the relay node with the optimal weighted metric is selected as the best one. Simulation re- suits are presented to demonstrate the effectiveness of the proposed scheme.

关 键 词：cognitive radio (CR) cooperative transmissions relay selection instantaneous channel state information (ICSI) residual energy 

分 类 号：TN925[电子电信—通信与信息系统]