Signal instantaneous frequency estimation method

Abstract

The invention discloses a signal instantaneous frequency estimation method, and relates to the technical field of signal processing methods. The method comprises the following steps: inputting a signal and initializing each variable; performing two-dimensional search on the i-th signal to obtain an optimal parameter, and extracting instantaneous frequency estimation of the i-th signal under the optimal parameter; solving the time domain representation of the i-th signal, and subtracting the i-th signal from the original signal to obtain the remaining (i+1)-th signal; repeating the above stepsuntil the energy of the remaining components is less than a set threshold value; and finally, adding the obtained instantaneous frequency estimation of the components to realize instantaneous frequency estimation of the multi-component non-stationary signal. The method provided by the invention not only has adaptability to the number of signal components and relatively strong noise robustness, butalso improves the signal time-frequency distribution energy aggregation and instantaneous frequency estimation precision.

Description

Technical field [0001] The present invention relates to the field of signal processing, and more particularly to a signal instantaneous frequency estimation method. Background technique [0002] The instantaneous frequency is a feature amount that states the physical essence of non-steady signals. It has been widely used in the field of radar, sonar, mobile communication, and rotary mechanical and other technical fields. It can fully show the signal frequency over time variations, and The degree of signal energy concentration can be observed in the time-frequency distribution. Therefore, the estimation method of the instantaneous frequency of the research signal is important and practical value. [0003] In recent years, the signal instantaneous frequency extraction method is mainly maping one-dimensional frequency domain and time domain signal to the two-dimensional time frequency domain plane, thereby obtaining the time-frequency distribution of the signal, and finally completi...

AI Technical Summary

Problems solved by technology

However, this type of synchronous compression algorithm mainly has two deficiencies. One is that this type of algorithm only has high frequency extraction accuracy for pure harmonic signals with constant instantaneous frequency, and when the instantaneous frequency changes sharply, the instantaneous frequency extraction of synchronous compression transform low precision

Therefore, this algorithm is not suitable for extracting the instantaneous frequency of non-pure harmonic signals; secondly, non-stationary bearing vibration signals usually contain multiple components in practical applications, and they not only appear simultaneously in the time domain, but also the instantaneous frequency may be in the frequency domain. The overlap in the domain or the difference in the instantaneous frequency of each component is small. At this time, the clearest and true time-frequency information cannot be obtained by using this type of synchronous compression algorithm.

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