关键词: 参数方程, 适应度函数, 遗传算法, 自适应小波

Abstract: The parametric representation for wavelet base is researched and wavelet base’s two parametric equations including different parameters are obtained. It’s pointed out that signal’s adaptive wavelet decomposition can be realized through parameters being searched in parametric equation. Two fitness functions are defined to appraise wavelet bases’ decomposing effect for different applying purpose. The non-linear relationship between the fitness and parameters being taken into account, an improved genetic algorithm is proposed to search parameters in wavelet parametric equation and at the same time the fitness function is used to appraise the analyzing effect of the searched wavelet base. When the fitness gets the maximum value then the optimal wavelet base can be searched. A milling force signal’s adaptive wavelet decomposition is brought into effect by virtue of this algorithm and is compared with Daubechies wavelet’s decomposing results. The comparing results show that adaptive wavelet can extract much more useful information from signal than Daubechies wavelet.

Key words: Adaptive wavelet, Genetic algorithm, Fitness function, Parametric equation