摘要： 利用IEEE 802.22标准草案中的预留信道机制，分析和描述认知无线电的3种基本频谱切换方案。针对预留信道机制以牺牲新呼阻塞率换取较低切换阻塞率的不足，提出对新呼用户进行排队缓冲的方法，并利用二维马尔可夫模型和排队理论，给出其状态转移图。仿真结果表明，该方法在保证切换性能的条件下，能有效降低新呼阻塞率，并使GoA值大幅下降。

关键词: 认知无线电, 频谱切换, 预留信道机制, 恶劣等级

Abstract: Three basic types of spectrum handoff scheme in Cognitive Radio(CR) network are described by using channel reservation mechanism, which is proposed by draft standard of IEEE 802.22. This scheme decreases blocking probability of switching with the cost of new-call blocking probability. To reduce the cost, a method with buffering for the new call is proposed. Two-dimensional Markov model and queuing theory are used to obtain its state transition graph. Numerical results show that, with the performance of switching guaranteed, the proposed method can greatly reduce the blocking probability of new call and the value of Grade of Annoyance(GoA).

Key words: Cognitive Radio(CR), spectrum handoff, channel reservation mechanism, Grade of Annoyance(GoA)

中图分类号: 

• TN915