认知无线网络信道接入协议

摘要

由于认知无线网络(cognitive radio network,简称CRN)固有“二次利用”的特性,使其日益得到重视.而作为CRN核心构成的MAC(medium access control)协议,业已成为当前各研究机构的一个热点.主要对频谱感测技术、信道接入技术等MAC层核心设计问题进行了探讨,并针对认知无线网络MAC的特性及需求进行了分析,然后对设计MAC频谱感知技术、信道接入技术、频谱共享技术等相关研究进展进行了归类总结.最后指出了当前面临的主要研究难点及挑战,并提出了一些方向性建议.%The cognitive radio network (CRN) has been paid more attentions as it can enable the device to dynamically access unused spectrum without interference to primary users (Pus). The medium access control (MAC) protocol of CRN, has being intensively researched for its key function position. This paper reviews the demand of MAC for CRN, the state-of-the-art spectrum sensing technology, and a detailed classification of the MAC protocols. In this overview, the characteristic features, advantages, and the limiting factors of the existing CRN MAC protocols are thoroughly investigated for both underlay-based and overlay-based networks. Several challenges and future research directions are also presented in this paper.