Fourier series

例句：

1. 1.In the analysis of complex signals, Fourier series are often used to decompose them into their constituent frequencies.
   在分析复杂信号时，傅里叶级数常被用来将它们分解为它们的组成部分频率。
2. 2. The Fourier series representation is a powerful tool for analyzing the behavior of waves in different media.
   傅里叶级数表示是一种强大的工具，用于分析不同介质中波的行为。
3. 3.The Fourier series method is widely used in engineering and scientific fields to model the behavior of systems with time-varying parameters.
   傅里叶级数方法在工程和科学领域中广泛使用，用于模拟具有时间可变参数的系统行为。