ex6_45.m

ex5_1 I-型线性相位FIR滤波器 ex5_2 II-型线性相位FIR滤波器 ex5_3 III-型线性相位FIR滤波器 ex5_4 IV-型线性相位FIR滤波器 ex5_5 矩

fs = 1000;
h = fir1(20, 0.3);
r = randn(1024, 1);
x = filter(h, 1, r);
[P1, f] = pcov(x, 20, [], fs);
[P2, f] = pmcov(x, 20, [], fs);
Pxx1 = 10 * log10(P1);
Pxx2 = 10 * log10(P2);
plot(f, Pxx1, ':', f, Pxx2, '-.');
ylabel('幅值（dB）');
xlabel('功率谱估计');
legend('协方差法','改进的协方差法');