无线多载波信道的保密容量及最优功率分配  

Secrecy capacity and optimal power allocation over wireless multi-carrier channel

作　　者：曾伟超[1] 陈雁[1] 余官定[1] 仇佩亮[1] 

机构地区：[1]浙江大学信息与电子工程学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2008年第8期1281-1285,共5页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(60472079;60572115);教育部博士点基金资助项目(20040335099)

摘　　要：从信息论的角度,研究了宽带通信系统以多载波方式传输时可以实现的保密通信容量问题.将传统多载波窃密(wiretap)信道模型推广到多载波系统,推导了窃密信道可达保密容量的计算公式.在发送端总功率受限的条件下,进一步建立了最大化保密容量的优化模型,并根据发送端信道条件获知程度的不同,提出了相应的多载波最佳功率分配策略.仿真与分析结果表明,与发送端均匀分配功率相比,利用不同获知程度的信道状态信息,经过功率优化分配,可以提高保密容量.The secrecy capacity of broad-band multi-carrier communication system was studied from an information-theoretic perspective. The traditional model of wiretap channel was extended to the multicarrier system, and the exact expression of the secrecy capacity over multi-carrier wiretap channels was obtained. On the assumption of overall transmit power constraint, an optimization model that aimed at maximizing the secrecy capacity was further established, and the corresponding optimal power allocation strategies were proposed according to different degrees of channel state information （CSI） available at the transmitter. Simulation showed that, by exploiting the available CSIs, the achievable secrecy capacity via optimal power allocation is greatly improved, compared with that under uniform power allocation.

关 键 词：窃密信道 保密容量 功率优化分配 

分 类 号：TP13[自动化与计算机技术—控制理论与控制工程]