FIR(Finite Impulse Response)滤波器：有限长单位冲激响应滤波器，又称为非递归型滤波器，是数字信号处理系统中最基本的元件，它可以在保证任意幅频特性的同时具有严格的线性相频特性，同时其单位抽样响应是有限长的，因而滤波器是稳定的系统。因此，FIR滤波器在通信、图像处理、模式识别等领域都有着广泛的应用。(FIR (Finite Impulse Response) Filter: Finite-length unit Impulse response filter, also known as non-recursive filter, is the most basic component of digital signal processing system, it can guarantee arbitrary amplitude characteristics at the same time with strict Of the linear phase-frequency characteristics, while the unit sampling response is finite, so the filter is a stable system. Therefore, FIR filter in communication, image processing, pattern recognition and other fields have a wide range of applications.)