% 第六章：例6.7
% 頻率采樣形式: 給定頻率樣本
%
M = 32; alpha = (M-1)/2; k = 0:M-1; wk = (2*pi/M)*k;
magHk = [1,1,1,0.5,zeros(1,25),0.5,1,1];
k1 = 0:15; k2 = 16:M-1;
angHk = [-alpha*(2*pi)/M*k1, alpha*(2*pi)/M*(M-k2)];
H = magHk.*exp(j*angHk);
h = real(ifft(H,M));
[C,B,A] = dir2fs(h)