Signal feature extraction method and system based on synchronous compression transformation and time-frequency matching

Abstract

The invention provides a signal feature extraction method based on synchronous compression transformation and time-frequency matching. The method comprises the steps of S1 acquiring high-resolution time-frequency distribution of an original signal in combination with time-frequency domain transformation and synchronous compression transformation; S2 setting a time-frequency matching template, andcalculating a time center and a characteristic frequency of high-resolution time-frequency distribution through the time-frequency matching template; and S3 performing secondary sampling in combination with the time center and the characteristic frequency to obtain a correction signal, and performing fault analysis and diagnosis according to the correction signal. According to the method, the problems of signal distortion and characteristic frequency aliasing caused by nonlinear Doppler interference in an existing train rail side acoustic monitoring system can be well solved; a microphone array is not needed, so that the cost and the installation complexity are reduced; the estimation precision of signal Doppler parameters and the correction effect of distortion are improved; and higher robustness is achieved for different background noises.

Description

technical field [0001] The invention relates to the technical field of signal processing, in particular to a signal feature extraction method and system based on synchronous compression transformation and time-frequency matching. Background technique [0002] Railway transportation is also a pillar industry of the national economy and is irreplaceable in the entire field of transportation. With the rapid development and continuous speed-up of modern railway transportation, the demand for railway transportation is getting higher and higher, and the safety problems in the process of train operation have become increasingly prominent. The main types of train failures during train bearing failures are also one of the biggest root causes that affect train safety. [0003] Generally, the working environment of train bearings is very harsh, and the effect of alternating stress makes them often fail, and bearings have an irreplaceable position in all parts of trains. In this speci...

AI Technical Summary

Problems solved by technology

However, most of these algorithms can only contain a single frequency component when processing the original signal in the frequency domain, and it is difficult to effectively extract time-varying features and remove Doppler interference when the characteristic frequency distribution is relatively dense; The endpoint effect of the subsampling of the Hulbert transform will affect the effectiveness of the method and reduce the estimation accuracy of the frequency parameter

[0013] (3) There are still some methods that have higher requirements on the collected signal or require more hardware to realize

For example, the above-mentioned distortion elimination based on the microphone array needs to install more microphone arrays, and the design of the array will directly affect the signal processing results; Influenced by occasional high-energy frequency components, when the signal contains occasional strong noise, the extracted instantaneous frequency distribution will be inaccurate, affecting the judgment of the final result, and the convergence of the algorithm will be directly affected by the noise

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