Abstract: Cognitive Radio（CR） technology has been proposed as promising solutions to implement efficient reuse of the licensed spectrum by opportunistically utilizing the white space of licensed spectrum bands.In order to improve the search and utilization efficiency of licensed bands，a simple and effective method is proposed.The proposed method firstly determines the weighted coefficients of the available spectrum bands according to the traffic model of CR systems，and then calculates the opportunistic utilization quality of licensed bands by considering the occupancy state of licensed bands.Opportunity utilization quality of licensed bands indicates its capability to provide the available white space for CR systems.

Key words: Cognitive Radio（CR）, licensed band, spectral occupancy, energy perception and detection algorithm, opportunistic utilization quality

摘要： 认知无线电技术能利用暂时空闲的授权频段，被认为是解决当前无线电频谱资源稀缺的有效技术。为提高搜索授权频段的效率，提出了一种简单而有效的方法。此种方法，根据认知无线电系统业务模型确定可用授权频段的加权系数，联合授权频段的占用状况来计算授权频段的机会可用价值。授权信道的可用价值反映了信道为认知无线电系统提供空白频谱的能力。

关键词: 认知无线电, 授权频段, 频谱占用, 能量感知与检测算法, 机会可用价值