中文摘要：

在认知无线电中,次级用户对特定频段的主用户信号进行检测,以判断该频段是否能为自己复用.对主用户检测而言,检测精度和检测时间均是重要的性能指标.本文在保证所需检测精度的约束下,以基于AND准则和OR准则的主用户检测为例,分析了决策融合主用户检测的检测时间,并推导出了两种准则下平均检测时间的解析表达式.通过对比两种准则下的平均检测时间,本文还证明了,检测精度相同时,OR准则在检测时间方面优于AND准则.数值仿真验证了上述结论,并显示OR准则检测时间的优势在高检测精度约束或低信噪比的场景中更明显.

英文摘要：

In cognitive radio, secondary users detect primary user＇ s signal in a specific spectrum band to determine whether the band can be reused. For primary user detection, both of the detection accuracy and detection time are key performance indexes. This paper analyzed the detection time of decision fusion based primary user detection subject to the constraints of required detection accuracy. Two examples of AND rule as well as OR rule based primary user detection were considered, and analytic expressions for their average time were deduced. Moreover, by comparing the average detection time, this paper proved that OR rule was superior to AND rule from detection time point of view under the same accuracy constraints. Numerical simulation verified all the conclusions in this paper, and demonstrated that superiority of OR rule in detection time over AND rule was greater in the scenarios with higher accuracy constraints or lower signal to noise ratios.