多信道认知无线网络的k连通性研究

Cognitive radio ad hoc networks (CRAHNs), equipped with the intrinsic capabilities of the cognitive radio, will extend the communication range and improve networking flexibility. However, the time and location varying spectrum availability imposes unique challenges on the connectivity of CRAHNs. In this project, we study the connectivity of multi-channel CRAHNs. k-channel connectivity is introduced to measure the robustness of multi-channel CRAHNs. We examine the impacts of the desity of primary uses and secondary usrs, the activity probability of the primary users, and the number of availble channels on the connectivity and then derive the k-connectivity region of multi-channel CRAHNs. Furthermore, we combine interference cancellation, power control and channel assignment to optimize the topologies, which guarantee the k-channel connectivity and reduce the interference among secondary users. Finally, we design the distributed topology control protocol with low complextiy for large scale multi-channel CRAHNs. The achievements of this project will provide necessary theoretical and technical supports for future cognitive networks.

多个认知无线电节点以自组织方式组成的认知无线网络，可以提高区域的覆盖度和组网的灵活度，但由于授权用户对认知用户的影响在时域上动态变化而且在空域上具有相关性，使得认知无线网络的连通性难以保证，进而影响网络的端到端业务性能。本项目旨在研究多信道认知无线网络的连通性，定义k信道连通作为多信道认知无线网络拓扑鲁棒性的衡量标准，分析授权用户密度、占用信道概率、认知用户密度、可用信道数与网络连通性的本质关系，给出多信道认知无线网络的k信道连通域，并在此基础上，对多信道认知无线网络的拓扑进行优化，联合干扰消除、功率控制、信道分配等多种手段构建具有良好性质的拓扑结构，在保证多信道认知无线网络k信道连通的同时，减小认知用户之间的干扰并提高网络容量，最后面向大规模多信道认知无线网络设计低复杂度的分布式拓扑控制协议。本项目的研究为认知无线网络的规模化应用提供理论基础和技术支撑。

针对认知无线网络，本项目分析了多信道认知无线网络的连通性，刻画了授权用户密度、占用信道概率、认知用户密度和可用信道数对网络连通性的影响；联合了干扰消除、功率控制和信道分配构建网络拓扑，保证了多信道认知无线网络的2信道连通，同时避免了认知用户之间的干扰，实现了无冲突传输；设计了面向大规模多信道认知无线网络的分布式拓扑控制协议，降低了协议的计算复杂度和通信复杂度， 为认知无线网络的规模化应用提供理论基础和技术支撑。本项目在国际重要期刊和会议上发表论文10篇，申请国家发明专利5项，其中授权专利2项。