基于功率谱和双门限的频谱感知算法

A spectrum sensing algorithm based on power spectrum and double-threshold

传统双门限能量检测算法需通过已知的噪声方差来确定门限,检测性能较差,为此,提出一种基于功率谱和双门限的频谱感知算法。首先,将功率谱的最大最小值之差与功率谱最小值之比作为双门限间检测判决统计量;然后,利用功率谱计算信号能量,利用估计的噪声方差计算能量检测法门限,降低了噪声对算法检测性能的影响。仿真结果表明,在加性高斯白噪声信道和瑞利衰落信道下,提出算法抗噪声功率不确定性能力强;且当频偏系数由0.04增加到0.06时,提出算法的检测性能恶化小于对比算法,具有更强的抗频偏能力。

Because the detection performance of the traditional dual-threshold energy detection algorithm between dual thresholds is poor,and the threshold of the energy detection algorithm requires a known noise variance,a spectrum sensing algorithm based on power spectrum and dualthreshold is proposed.Firstly,the ratio of the difference between the maximum and minimum values of the power spectrum to the minimum value of the power spectrum is used as the detection decision statistic between the double thresholds.Then,the power spectrum is used to calculate the signal energy,and the estimated noise variance is used to calculate the threshold of the energy detection algorithm,which reduces noise impact on detection performance.Simulation results show that under the additive white Gaussian noise channel and Rayleigh fading channel,the proposed algorithm has a strong ability to resist the uncertainty of noise power,and when the frequency offset coefficient increases from 0.04to 0.06,the detection performance of the algorithm deteriorates lower than that of the compared algorithm,it has stronger anti-frequency offset ability.