基于改进经验AM-FM解调的复杂信号瞬时特征分析方法

分析了Hilbert变换在计算复杂单分量信号瞬时特征时存在的不足,研究了一种称为经验AM-FM解调的信号瞬时特征计算方法,并对算法进行了改进.针对其在计算瞬时频率时易受噪声影响的不足,提出将该算法与加权平滑相位差分法相结合来抑制噪声的影响.结合经验模式分解和改进的经验AM-FM解调算法,提出了一种适合复杂多分量信号解调...

Instantaneous Characteristics Analysis Method for Complicated Signals Based on Improved Empirical AM-FM Demodulation

Some limitations of the Hilbert transform (HT) for computing instantaneous characteristics of complicated mono-component signals were analyzed. As an enhancement of the HT, an algorithm named empirical AM-FM (amplitude and frequency modulation) demodulation was investigated and then improved. Firstly, the weighted smoothing phase-difference method was applied to this demodulation algorithm to increase the precision of instantaneous frequency for noisy signals. Secondly, by combining the Empirical Mode Decomposition (EMD) and the improved empirical AM-FM demodulation algorithm, a method suitable for instantaneous characteristics extraction of complicated multi-component signals was proposed. The validity of the improvements was confirmed by numerical simulations and experimental signals.