Abstract：A new adaptive radial Mexican-hat kernel (RMK) time-frequency distribution method is proposed according to the design criteria of adaptive optimal kernel. The characteristic of the proposed method is that RMK can self-adaptively adjust the expansion direction and width of the kernel function according to the distribution of the analyzed signal. The RMK is as far as possible extended in auto-term direction, and as far as possible suppressed in cross-term direction, overcomes the deficiency of the fixed kernel in the traditional time-frequency distribution ,which is lack of self- adaptability. In this paper, the definition and the algorithm of RMK are given, and the proposed method is compared with the traditional time-frequency distribution, such as short Fourier transform, Wigner-Ville distribution and wavelet transform. The simulation results show that the proposed method is superior to the traditional time-frequency distribution, can be effectively process the non-stationary signal, and obtain the higher time-frequency resolution and the anti-interference performance. Finally the proposed method is applied to the fault diagnosis of rotor crack , the experiment results show that the proposed method is very effective and can be discern the severity of rotor crack fault.
李志农，朱 明，龙盛蓉. 新非平稳信号分析方法—自适应径向墨西哥草帽核时频分布[J]. 振动与冲击, 2015, 34(10): 184-190.
LI Zhi-nong，ZHU Ming，LONG Sheng-rong. A new method for non-stationary signal analysis-adaptive radial mexican-hat time-frequency representation. JOURNAL OF VIBRATION AND SHOCK, 2015, 34(10): 184-190.
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