非理想报告信道下协作频谱感知研究及性能分析

Performance Analysis and Research of Cooperative Spectrum Sensing under the Imperfect Report Channel

分析了理想报告信道下协作频谱感知性能,提出了基于改进的能量检测的协作频谱感知方案。改进的能量检测器通过对接收信号样本取任意正数p次方的和作为检测统计量,每一个认知用户将本地检测结果发送到数据融合中心,数据融合中心采用OR准则最终判断授权用户信号是否出现。针对非理想报告信道情况,推导了误检概率最小下参与协作的认知用户个数,并数值仿真得到了误检概率最小下的p值。数值仿真结果也表明协作频谱检测概率在低信噪比情况下随着p值的增大而提高。

This paper analyzes the performance of cooperative spectrum sensing under the non-ideal report channel. A new cooperative spectrum sensing scheme is proposed based on the improved energy detector. The improved energy detector selects the sum of any positive p power of the signal samples as the test statistics. Each cognitive user sends the local decision to data fusion center, which takes the final decision of the presence of the authorized user using the OR rule. According to the no-ideal report channel, the closed-loop expression of the number of collaborating cognitive users is derived by minimizing the error probability. And the value of p is obtained by numerical simulation when the error probability is least. Numerical simulation results also show that the probability of detection increases with the raise of the value ofp.