fir滤波器，7、8、13、14，对信号进行alpha、beta\gamma滤波，调用方法 Hd = fir_alpha 滤波后信号 = filter(Hd,原信号) 得到的信号是时域信号，plot直接显示-Fir filter, 7, 8, 13, 14, alpha filter for signal method is called Hd = fir_alpha After filtering signal = filter (Hd, the original signal) Signal