ex0806.asv

数字信号处理（机械工业出版社）的源码

% Chapter 8: Example 8.6 Type-3 Linear phase FIR filter
%
h = [-4,1,-1,-2,5,0,-5,2,1,-1,4];
M = length(h); n = 0:M-1;
[Hr,w,c,L] = Hr_Type3(h);
cmax = max(c)+1; cmin = min(c)-1;
subplot(2,2,1); stem(n,h); axis([-1 2*L+1 cmin cmax])
xlabel('n'); ylabel('h(n)'); title('Impulse Response')
subplot(2,2,3); stem(0:L,c); axis([-1 2*L+1 cmin cmax])
xlabel('n'); ylabel('c(n)'); title('c(n) coefficients')
subplot(2,2,2);plot(w/pi,Hr);grid
xlabel('frequency in pi units'); ylabel('Hr')
title('Type-3 Amplitude Response')
subplot(2,2,4);zplane(h,1)