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声波测井信号通常包含几种不同模式的波，它们是由加窗的窄带信号产生且具有不同的主频，因此在时—频面中是可分的。根据这些波的不同特点，提出了基于时—频分解技术的各模式波的分离方法，把测井信号分解为一系列基本函数的线性组合，且它们在时—频平面上有良好的局部特性。根据时—频平面上的信号能量分布，可以得到各模式波的一种可能的分解，由此可进一步计算纵、横波时差，推断地下岩石特性。同时，各模式波也以解析的方式给出，有利于进一步的理论研究
Acoustic well logging signals typically contain several different modes of wave, which are produced from windowed narrow-band signals and have different dominant frequencies and are therefore separable in the time-frequency plane. According to the different characteristics of these waves, the method of separating each mode wave based on the time-frequency decomposition technique is proposed, which decomposes the logging signal into a linear combination of a series of basic functions and has good local characteristics in the time-frequency plane . According to the signal-energy distribution on the time-frequency plane, a possible decomposition of each mode wave can be obtained, which can further calculate the time difference between the longitudinal and transverse waves and infer the underground rock characteristics. At the same time, each mode wave is also given by analytical method, which is conducive to further theoretical research