基于高阶累积量实现数字调相信号调制识别

摘要

Theoretical analysis justifies that the ability of suppressing multi-path fa- ding improves as the order number of cumulants features increases. New features based on sixth-order cumulants are proposed for classification of M-ary phase shift keying（MPSK） signals. Performance of the proposed approach is demonstrated via computer simulations. The simulation results of correct classification probability show that sixth-order cumulants method works better than fourth-order cumulants under the deeply multi-path fading channel environments. The simulation results of variance of extraction features show that the fourth order cumulants method works better than sixth-order cumulants when the signal-to-noise ratio（SNR）is lower than or equal to 0 dB.%给出了基于高阶累积量进行多进制数字相位调制（MPSK）信号调制识别的特征值构造方法，对该特征值抑制多径干扰能力进行了理论分析，证明累积量阶数越高抑制多径干扰的性能越好。推导出基于6阶累积量进行MPSK信号调制识别的特征值公式，并给出具体分类方法，对4阶和6阶累积量调制识别性能进行了分析比较。计算机仿真试验证明：多径信道时，6阶累积量分类特征值优于4阶；当符号信噪比低于0dB时，4阶累积量分类特征值优于6阶。