针对认知无线电中主用户覆盖范围存在交叠区域的情况，给出先次用户分组再组内协作感知的方法. 首先提出一种基于简化置信传播(belief propagation, BP)的次用户频谱相似性分组算法，挖掘各次用户前一次频谱感知信息并提取相关参数，再根据相关参数利用BP算法对当前频谱感知次用户进行相似性分组. 在组内采用恢复效果较好的多任务压缩频谱感知方法来完成感知任务. 仿真结果表明，所提出的频谱感知方法与现有方法相比，能在混杂频谱环境下保证较好的虚警概率，同时提高频谱感知的正确检测概率，且随着全网感知用户数的增加，频谱感知结果也不断改善.
As coverage of primary users overlaps in cognitive radio, a method grouping secondary users first and cooperative spectrum sensing within group afterwards is introduced. A grouping algorithm using similarity of secondary users based on simplified belief propagation (BP) is proposed to exploit the previous spectrum sensing information of all secondary users and extract relevant parameters from the exploited information.The current secondary users are then grouped with the BP algorithm according to the extracted relevant parameters. We use a multi-task compressed spectrum sensing method with better recovery ability in current cooperative spectrum sensing methods within each group. Simulation results show that, in a heterogeneous spectrum situation, the proposed method can improve probability of correct detection of the spectrum sensing under better probability of false alarm compared to other methods. The spectrum sensing results are improved with the increasing of the sensing users.
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