针对认知网络中的频谱接入问题，基于多类用户不同带宽需求提出了一种新的频谱接入策略，即基于用户带宽的动态信道接入策略(BRDSA)。首次提出考虑拥有不同带宽需求的主用户和次用户利用频谱聚合技术进行频谱接入，而频谱聚合技术能够提高次用户对离散频谱的利用率。根据相关网络模型，利用排队理论和马尔科夫模型对整个系统状态进行了分析。仿真结果表明这种动态频谱接入策略极大地提高了频谱利用率。

Abstract：Concerning the spectrum access problem in cognitive radio network, a new spectrum access strategy Based on users’ Requirements Dynamic Spectrum Access(BRDSA) is proposed based on multiclass users’ different band requirements. It is the first time to consider the different band requirements of primary users and secondary users, using channel assembling technology which can help the user to utilize the discrete spectrum. According to the proposed network model, the queuing theory and Markov chain model are used to analyze the transformation of system status. The simulation results show that the BRDSA strategy can greatly improve the spectrum utilization.