作为一种新的非平稳信号处理方法，固有时间尺度分解法在将复杂的非平稳信号分解为若干个固有旋转分量过程中，存在着严重的边界效应问题。本文针对抑制边界效应提出了五种数据延拓方法：自适应波形匹配法、基于AR模型的延拓方法、镜像延拓方法、多项式延拓方法、反对称周期延拓法。通过数学模拟实验比较这五种方法的抑制效果，选出最优方法。将最优方法用于仿真信号和轴承故障振动信号分析，结果表明该方法能够有效地抑制边界效应，可更好地提取机电设备故障特征。%As a new non-stationary signal processing method,the intrinsic time-scale decomposition (ITD)method can be used to decompose a complex non-stationary signal into several proper rotation components (PRCs),but there exist serious end effects in some PRCs.Here,5 end effect-mitigation methods to deal with end effects were proposed including adaptive,AR prediction extending method,mirror extrema extending,polynomial fitting extending method and anti-symmetric period extension method.The end effect-restrained results with 5 methods were compared with numerical simulations.The best one was applied to analyze simulated signals and bearing fault vibration signals,the results showed that the proposed method can be used to solve the end effect problems effectively and to extract fault features of mechanical equipments better.
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