digital-band-pass-filter

代码说明：

  用凯瑟窗设计一个数字带通滤波器，设计指标为 低阻带：ws1=0.2pi,as=70dB, 低通带：wp1=0.35pi,ap=1dB, 高通带：wp2=0.65pi,ap=1dB, 高阻带：ws2=0.8pi,as=60dB(Kaiser window design with a digital band-pass filter design specifications for the Low resistivity zone: ws1 = 0.2pi, as = 70dB, Low-pass band: wp1 = 0.35pi, ap = 1dB, High-pass band: wp2 = 0.65pi, ap = 1dB, Impedance with: ws2 = 0.8pi, as = 60dB )