MATLAB绘制理想低通滤波器的冲激响应clear;close all;clc %1.数字滤波器的技术指标 ap = 1;%通带最大衰减 as = 30;%阻带最小衰减 fp = 208;%通带截止频率 fs = 488;%阻带截止频率 Fs = 1888;%抽样间隔 T = 1/Fs; %2.将数字指标转化成模拟滤波器技术指标《来用冲激响应不变法wap = 2*pi*fp!was = 2*pi*fs; %3.设计滤波器 [N,wac] = buttord(wap,was,ap,as,s');%计算阶数N和3dB截止频率wac[z,p,k] = buttap(N);%创建巴特沃斯低通滤波器 z零点p极点k增益[Bap,Aap] = zp2tf(z,p,k);%由零极点和增益确定归一化Han(s)系数[Bbs,Abs] = 1p21p(Bap,Aap,wac);%将s/wc