从数学的角度讲，小波是构造函数空间正交基的基本单元，是在能量有限空间L2(R) 上满足允许条件的函数，这样认识小波需要L2(R) 空间的基础知识，特别是内积空间中空间分解、函数变换等的基础知识。

从信号处理的角度讲，小波(变换)是强有力的时频分析(处理)工具，是在克服傅立叶变换缺点的基础上发展而来的，所以从信号处理的角度认识小波，需要傅立叶变换、傅立叶级数、滤波器等的基础知识。-From the mathematical point of view, is to construct a wavelet orthogonal basis function space the basic unit of energy is limited in space L2 (R) function to meet the permit conditions, such wavelets need to know L2 (R) space for the basics, especially in the inner product space in the space decomposition, such as the basics of function transformation.

　　　 From the perspective of signal processing, wavelet (transform) is a powerful time-frequency analysis (processing) tools, is to overcome the shortcomings of the Fourier transform on the basis of evolved, so from the perspective of wavelet signal processing, need to Fourier transform, Fourier series, filters and other basics.