Direct Calculation: The impulse responses of certain types of FIR filters (e.g. Raised Cosine and Windowed Sinc) can be calculated directly from formulas.

• 当然是用FIR设计程序呀.；虽然可以使用手工亲自的方法进行设计滤波器；但是使用FIR滤波器程序比较简单