中文摘要：

频谱感知是认知无线电中通过发现可用频率资源提高频谱利用率的关键技术。协作频谱感知能一定程度上消除多径和阴影的影响，为了进一步提高频谱检测性能，提出了一种基于SNR比较的协作频谱感知算法。在此算法中，各个认知用户将各自的本地判决结果和自身的SNR 值发送到数据融合中心，通过 SNR 比较，对各 CR 用户进行筛选，选出符合算法要求的CR用户参加协作检测，进行数据融合。计算机仿真表明，该算法能有效提高检测性能，并减少判决融合的节点数量。

英文摘要：

Spectrum sensing is one of the key technologies in cognitive radio,which improves the utilization ratio of spectrum by discovering available frequency resources. Cooperative spectrum sensing can eliminate the multi-path and shadow effects to a certain extent. A cooperative spectrum sensing algorithm based on SNR comparison is proposed, in which each CR user transmits the local decision result and estimated SNR to the data fusion center,and the CR users with SNRs that match the algorithm are selected for deci-sion fusion. Computer simulation results show that this algorithm increases the probability of detection and reduces the node number in decision fusion.