低信噪比下一种改进的谱相关频谱检测

针对现有基于谱相关频谱检测算法中周期图法谱估计精确度较低的缺点,提出了一种用主用户发送信号与认知用户接收信号的最小方差无失真响应(MVDR)谱的谱相关量作为检测统计量进行频谱检测的改进方法.由于MVDR谱估计算法比周期图法具有更高的分辨率,因此所提频谱检测算法比现有算法具有更好的检测效果.模拟了两种电视信号作为主用户发送信号,仿真结果表明:对于两种电视信号,所提算法的检测性能都优于现有算法,同时通过分析算法的复杂度,证明所提算法能够满足IEEE802.22标准对于检测时间的要求.

Improved spectral correlation spectrum detection at low SNR

The existing spectral correlation spectrum detection has a limitation due to the low spectrum resolution of periodogram spectrum estimation. The detection statistics to the improved spectrum detection algorithm is the correlation of MVDR Spectrums of the transmitted signal to the primary user, and the received signal to the cognitive user. The MVDR algorithm has higher resolution than the periodogram algorithm for spectrum estimation, so the proposed algorithm has a better detecting performance than the existing algorithm. Two TV signals are generated to simulate the transmit signal to primary users. Simulation results indicate that the proposed algorithm has a better detecting performance than the existing algorithm for both TV signals. The computational complexity of the proposed algorithm is also analyzed, we obtain this algorithm can satisfy the sensing time limitation required by IEEE 802.22 standard.