IIR滤波器设计 设计一个巴特沃思低通滤波器，其技术指标为：3dB带宽为，阻带截止频率为，阻带衰减大于30dB，采样间隔T=10us。-IIR filter design to design a Butterworth low-pass filter, its technical indicators: 3dB bandwidth, stopband cut-off frequency, stop-band attenuation greater than 30dB, sampling in