多径信道下基于高阶累积量的通信信号调制识别算法

Automatic Modulation Classification Using Cumulant Features for Communications via Multipath Channels

多径信道下通信信号的自动调制识别问题一直是一个难点和研究热点。传统的调制识别算法受多径信道的干扰往往会失效,提出了一种基于高阶累积量的调制识别算法,该算法通过高阶累积量计算、非线性方程组构建以及高斯牛顿法迭代求解等途径,减小了多径信道对高阶累积量匹配的干扰。实验表明,相比现有算法,文章算法不再局限于特定的多径信道,有较强的普适性,减小了信道因子分布对识别算法的影响,在多径信道环境下保持了较高的识别率。

Automatic modulation recognition for communications via multipath channels has always been a difficult and hot topic. Conventional modulation recognition algorithms tend to fail to operate when disturbed by multipath channels. This paper proposes an algorithm of automatic modulation classification based on high-order cumulant features. By means of computing cumulants,construction of nonlinear equations,and the Gauss-Newton iterative method,the algorithm reduces the interference of multipath channels to the matching of high-order cumulants. Simulation results show that the algorithm is no longer limited to a particular multipath channel compared with existing algorithms,and has strong universality. It reduces the interference of channel coefficient distribution to the identification of signals,and maintains a high rate of correct identification under the condition of multipath channels.