chafenlvbo.m

来自「把信号用数字或符号表示成序列」· M 代码 · 共 21 行

% 差分方程1：y[n]-0.268y[n-1]=0.634x[n]-0.634x[n-1]
% 差分方程2：y[n]+0.268y[n-1]=0.634x[n]+0.634x[n-1]

close all
clear
load dajiahao;

[h,w]=freqz([0.634,-0.634],[1,-0.268],512,'whole');
subplot(121);plot(w,abs(h));subplot(122);plot(w,abs(h));xlabel('数字域频率w：0～2pi');

[h,w]=freqz([0.634,0.634],[1,0.268],512,'whole');
figure;subplot(121);plot(w,abs(h));subplot(122);plot(w,abs(h));xlabel('数字域频率w：0～2pi');

y1=filter([0.634,-0.634],[1,-0.268],x);
y2=filter([0.634,0.634],[1,0.268],x);
pause;disp '原始声音'
sound(x,22050,8);
pause;
sound(y1,22050,8);sprintf('y1能量比 = %f',sum(abs(y1).^2)/sum(abs(x).^2))
pause;
sound(y2,22050,8);sprintf('y2能量比 = %f',sum(abs(y2).^2)/sum(abs(x).^2))