认知无线电技术被认为是解决目前频谱资源利用率低下问题最有前景的技术，基于该技术，认知无线电网络采用动态频谱接入方式有效地提高了授权频段的利用率.然而，动态变化的信道可用性极大地增加了认知无线电网络组网的难度.信道交汇旨在为用户通信提供公共传输媒介，是实现无线网络组网的基础.介绍了认知无线电网络信道交汇的基本概念和特点，并阐述了信道交汇策略设计面临的挑战以及应考虑的性能指标.提出了信道交汇策略的分类标准和系统模型，根据该分类标准，详细剖析了当前信道交汇策略相关的研究工作.最后，讨论了认知无线电网络信道交汇研究的开放性问题，以期为未来的研究指出可能的方向和重点.

Cognitive radio technology is regarded as the most promising technique to solve the problem of ultra-low utilization efficiency of wireless spectrum resources. Based on this technology, cognitive radio networks (CRNs) effectively improve utilization efficiency of licensed spectrum through dynamic spectrum access. However, the resultant dynamic channel availability significantly increases the difficulty in networking for CRNs. Rendezvous aims at providing common media for communication between users, which is the foundation of networking in wireless networks. This paper introduces the basic concept and characteristics of rendezvous in CRNs and dissect the challenges and concerned performance metrics in design of rendezvous schemes. According to the proposed classification criteria and system models, the related research work on rendezvous schemes are analyzed in depth. Finally, open problems in rendezvous schemes design are discussed to point out future research trends and focuses.

国家自然科学基金（61070203，61202484）