Secure Communications in Fading Cognitive Radio Networks with Finite-Alphabet Signaling

目的：本课题的研究目标是建立频谱共享认知无线电网络安全通信的变革性方法和新算法，在安全威胁下最大化次用户的保密吞吐量，同时保证主用户的服务质量，并使信息对窃听者保密。智力价值：智力价值在于：1）提出了一个统一的网络模型来描述衰落认知无线电网络，该网络由多个主用户、次用户和中继节点组成，所有节点都通过无线衰落信道连接; 2）利用有限字母表将次用户的安全通信问题直接转化为互信息或吞吐量的最大化问题（而不是高斯）信令和信道几何约束; 3）提出一种新的方法来解决既不凹也不凸的优化问题。更广泛的影响：更广泛的影响包括：1）本项目将弥合网络信息理论与实际网络实现之间的差距，字母信令和信道统计，以优化线性预编码器，从而最大化实际可实现的数据速率或吞吐量; 2）它将建立一种有效解决困难的非凹，非凸，以及认知无线电网络中的非确定性多项式时间（NP）硬优化问题。该方法可以很好地应用于其他无线网络环境，如协作中继网络，蜂窝网络，无线传感器和网状网络; 3）该研究将及时融入与工业合作伙伴的合作以及本科生和研究生的教育，特别是少数民族学生，从而通过技术创新增强对社会的影响。

Objective:The objective of this program is to establish transformative methodology and novelalgorithms for secure communications in spectrum sharing cognitive radio networks tosimultaneously maximize the secrecy throughput of secondary users under securitythreats, ensure the quality of service for primary users, and keep information secret toeavesdroppers.Intellectual merit:The intellectual merit is: 1) to propose a unified network model to describe the fadingcognitive radio network that has multiple primary users, secondary users andeavesdroppers, all connected by wireless fading channels; 2) to formulate the securecommunication of secondary users into direct maximization of mutual information orthroughput with finite-alphabet (rather than Gaussian) signaling and channel statisticsconstraints; 3) to present a novel approach to solving the neither concave nor convexoptimization problem.Broader impacts:The broader impacts include: 1) this project will bridge the gap between networkinformation theory and practical network implementation by employing finite-alphabetsignaling and channel statistics to optimize linear precoders which maximize thepractically achievable data rates or throughput; 2) it will establish a transformativemethodology that effectively tackles difficult non-concave, non-convex, and nondeterministicpolynomial-time (NP) hard optimization problems in cognitive radio networks. This methodology can be well applicable to other wireless network settingssuch as cooperative relay networks, cellular networks, and wireless sensor and meshnetworks; 3) The research will be timely integrated to collaborations with industrialpartners and education of undergraduate and graduate students, particularly, underrepresentedminority students, thus enhancing the impact to the society via technology innovation.