基于听觉分流机制的瞬态信号提取方法

Method for Transient Signal Extraction Based on the Mechanism of Auditory Stream Segregation

以听觉分流机制为基础,提出一种瞬态信号自动提取方法。首先,对信号进行带通滤波和相位调整;其次,获得各滤波信号二次包络的极大、极小值及其对应时间,基于两种极值幅值和时间,计算得到同步性和瞬态性线索;最后,综合这两类线索信息,在时频平面中筛选出与瞬态成分相对应的时频段,并最终完成瞬态成分的波形生成与修整。通过数值仿真和实测信号检验,所提方法能够在较强的背景信号下有效提取出瞬态信号,对瞬态信号的初始时间具有较高的识别精度,具有一定的实际应用潜力。

A transient vibration signal is generally induced by impact between parts in a mechanical system,so transient signal extraction is significant for the condition judgment and fault diagnosis of the machine.Considering that the human auditory system possesses the ability to segregate a novel burst signal stream in a multi-source sound field,a method for extracting the transient vibration signal component is proposed based on the mechanism of auditory stream segregation.First,band-pass filtering is used to obtain the time-frequency distribution of the analyzed signal.Then,the phase is adjusted using inverted filtering in every filter channel.Based on the maximum and minimal value of twice envelope of each filter signal,two cues(synchronism and mutation degree)are calculated to be used as index to screen out the timefrequency segments that are relevant to the transient signal component.Finally,these time-frequency segments are added together to generate the waveform of the transient signal.Numerical simulation and the analysis of signals measured from the gear box show that the proposed method can extract a transient signal component from a powerful background signal with high accuracy of onset time,and has utilization potential.