【摘要】 在希尔伯特—黄变换的筛选过程中,用三次样条插值法求取极值包络通常会出现"过冲"问题。根据本征模态分解原理,提出了极值序列加密方法,并通过与极值延拓法结合,得到改进的HHT,该算法可以较好的改善"过冲"问题,得到更为准确的信号特征。应用改进的HHT方法分析了线性调频连续波(FMCW)信号,仿真结果表明了改进方法对于低信噪比条件下线性调频信号的提取更彻底,参数估计更准确。更多还原

【Abstract】 In the shifting process of Hilbert-Huang transform,there is usually an "overshoot and undershoot" problem by using cubic spline interpolation method for the extremum envelopes.Based on the theory of Empirical Mode Decomposition,a method of increasing the extreme points into the extreme sequence is proposed.Combining with the boundary endpoint extension method,this method can improve the "overshoot and undershoot" problem and get more accurate signal characteristics.For frequency modulation continuous wave,the simulation results show that the improved HHT method can extract more characteristics for the low SNR non-stationary signals than the conventional HHT method,and the parameter estimations are more accurate.更多还原