Performance analysis of cognitive relay systems with spectrum- sharing interference under a primary outage probability constraint  

作　　者：YAN Sheng-nan LI Yan 

机构地区：[1]College of Information Science and Engineering,Yanshan University [2]School of Information and Communication Engineering,Beijing University of Posts and Telecommunications

出　　处：《The Journal of China Universities of Posts and Telecommunications》2014年第1期16-21,共6页中国邮电高校学报（英文版）

基　　金：supported by the National Nature Science Foundation of China(51204145);the Science and Technology Research and Development Program of Qinhuangdao(201302A033)

摘　　要：This paper investigates the performance of an underlay cognitive relay system where secondary users（SUs） suffer from a primary outage probability constraint and spectrum-sharing interference imposed by a primary user（PU）. In particular, we consider a secondary multi-relay network operating in the selection decode-and-forward（SDF） mode and propose a best-relay selection criterion which takes into account the spectrum-sharing constraint and interference. Based on these assumptions, the closed-form expression of the outage probability of secondary transmissions is derived. We find that a floor of the outage probability occurs in high signal-to-noise ratio（SNR） regions due to the joint effect of the constraint and the interference from the PU. In addition, we propose a generalized definition of the diversity gain for such systems and show that a full diversity order is achieved. Simulation results verify our theoretical solutions.This paper investigates the performance of an underlay cognitive relay system where secondary users（SUs） suffer from a primary outage probability constraint and spectrum-sharing interference imposed by a primary user（PU）. In particular, we consider a secondary multi-relay network operating in the selection decode-and-forward（SDF） mode and propose a best-relay selection criterion which takes into account the spectrum-sharing constraint and interference. Based on these assumptions, the closed-form expression of the outage probability of secondary transmissions is derived. We find that a floor of the outage probability occurs in high signal-to-noise ratio（SNR） regions due to the joint effect of the constraint and the interference from the PU. In addition, we propose a generalized definition of the diversity gain for such systems and show that a full diversity order is achieved. Simulation results verify our theoretical solutions.

关 键 词：cognitive relay systems spectrum-sharing interference outage probability diversity gain 

分 类 号：TN925[电子电信—通信与信息系统]