A hybrid carrier（HC） scheme based on weighted-type fractional Fourier transform（WFRFT） has been proposed recently.While most of the works focus on HC scheme＇s inherent characteristics, little attention is paid to...A hybrid carrier（HC） scheme based on weighted-type fractional Fourier transform（WFRFT） has been proposed recently.While most of the works focus on HC scheme＇s inherent characteristics, little attention is paid to the WFRFT modulation recognition.In this paper, a new theory is provided to recognize the WFRFT modulation based on higher order cumulants（HOC）. First, it is deduced that the optimal WFRFT received order can be obtained through the minimization of 4 th-order cumulants, C_（42）. Then, a combinatorial searching algorithm is designed to minimize C_（42）.Finally, simulation results show that the designed scheme has a high recognition rate and the combinatorial searching algorithm is effective and reliable.展开更多
针对采用Hammerstein模型描述电磁脉冲效应时模型参数确定困难的问题,提出一种基于优化Hammerstein模型的非线性电磁脉冲效应建模仿真方法。该方法利用高阶累积量求解模型线性延迟阶数,采用赤池信息准则(Akaike Information Criterion,A...针对采用Hammerstein模型描述电磁脉冲效应时模型参数确定困难的问题,提出一种基于优化Hammerstein模型的非线性电磁脉冲效应建模仿真方法。该方法利用高阶累积量求解模型线性延迟阶数,采用赤池信息准则(Akaike Information Criterion,AIC)优化模型非线性阶次,两者共同确定出一个参数最少、精度较高的最优模型,并以瞬态抑制器的电磁脉冲效应建模为例验证了该方法。展开更多
基金supported by the National Natural Science Foundation of China(6127125061571460)
文摘A hybrid carrier（HC） scheme based on weighted-type fractional Fourier transform（WFRFT） has been proposed recently.While most of the works focus on HC scheme＇s inherent characteristics, little attention is paid to the WFRFT modulation recognition.In this paper, a new theory is provided to recognize the WFRFT modulation based on higher order cumulants（HOC）. First, it is deduced that the optimal WFRFT received order can be obtained through the minimization of 4 th-order cumulants, C_（42）. Then, a combinatorial searching algorithm is designed to minimize C_（42）.Finally, simulation results show that the designed scheme has a high recognition rate and the combinatorial searching algorithm is effective and reliable.
文摘研究人脑在不同运动状态下的脑电信息,不仅能够揭示出各种运动状态对于大脑活动的影响,也是工程技术人员设计脑-机接口与神经修复系统的关键技术之一。文章根据脑电信号的μ节律变化,首次将表征时间序列摆动特性的高阶过零分析(Higher Order Crossing,HOC)方法运用于运动状态下的脑电信号的特征提取并结合支持向量机(Support Vector Machine,SVM)对输入的高阶过零特征量进行了有效的分类。将该方法提取的特征量与基于统计学的特征量分别用SVM进行分类,结果表明本方的识别率明显高于基于统计学特征量的方法。说明基于HOC-SVM方法在脑电信号的特征提取与分类中有较强的可行性和实用性。
文摘针对采用Hammerstein模型描述电磁脉冲效应时模型参数确定困难的问题,提出一种基于优化Hammerstein模型的非线性电磁脉冲效应建模仿真方法。该方法利用高阶累积量求解模型线性延迟阶数,采用赤池信息准则(Akaike Information Criterion,AIC)优化模型非线性阶次,两者共同确定出一个参数最少、精度较高的最优模型,并以瞬态抑制器的电磁脉冲效应建模为例验证了该方法。
