Train bearing rail side acoustic signal active noise reduction method based on double microphones

Abstract

The invention discloses a train bearing rail side acoustic signal active noise reduction method based on double microphones. The method comprises: placing two microphones beside a rail, a main microphone being right opposite to a wheel set bearing, a reference microphone being right opposite to a wheel track contact position, the two microphones being located on the same vertical line, and the twomicrophones synchronously collecting sound, wheel track contact noise and background noise generated by the wheel set bearing; then carrying out demodulation and re-modulation processing on the signals acquired by the reference microphones, so that Doppler distortion rules of the noise signals acquired by the two microphones are consistent; and finally, using a least mean square algorithm for completing active noise reduction of train bearing rail side acoustic signals. Double microphones are adopted to realize denoising of train bearing rail side acoustic signals, the method has the advantages that the number of the microphones is small, in-band noise can be eliminated and adaptive active noise reduction can be realized, and the signal-to-noise ratio of the train bearing rail side acoustic signals can be effectively improved. The method can be used for train bearing rail side acoustic fault diagnosis.

Description

technical field [0001] The invention belongs to the field of fault diagnosis of high-speed train bearings, and in particular relates to a dual-microphone-based active noise reduction method for train bearing trackside acoustic signals. Background technique [0002] As an important means of transportation in the world, the safe operation of trains is directly related to the safety of property and the safety of passengers. As the key components of trains, the real-time monitoring and diagnosis of wheel-set bearings is particularly important. The trackside acoustic diagnosis technology uses microphones placed on both sides of the rail to collect the sound signal from the bearing when the train passes, and obtains the health status information of the bearing through signal processing. However, since the sound signal emitted by the bearing in the early stage of the fault is relatively weak, it is often submerged by noise, which brings difficulties to accurate diagnosis. In the t...

AI Technical Summary

Problems solved by technology

In the field of signal processing, traditional digital filtering technology is difficult to eliminate in-band noise, and it is easy to cause distortion of target sound source information, and the denoising effect needs to be further improved

On the other hand, the existing array scheme uses a large number of microphones, the array signal processing algorithm is complex, and the directional filter used has side lobes, and the denoising effect needs to be improved

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