的傅立叶变换,工程技术中，常将看成一时间信号，相应的空间，称为时间域和空域；将其傅立叶变换看成频率函数，相应的空间称为频域。称为其相角，这在物理上是有良好背景的。-The Fourier transform, engineering technology, often viewed as a time signal, the corresponding space, known as time domain and airspace its Fourier transform as a fre