exmp6_3.m

来自「用dsp解压mp3程序的算法」· M 代码 · 共 18 行

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% exmp6_3.m - MATLAB M-file for example 6-3
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

b=0.4*sinc(0.4*(-25:25)); % rectangular windowed LPF
bw=b.*hamming(51)';       % Hamming windowed LPF
[H1,w]=freqz(b,1,512,2);  % frequency response of LPF
H2=freqz(bw,1,512,2);     % frequency response of Hamming LPF
H=[H1 H2];                % plot both response
s.xunits = 'rad/sample';
s.yunits = 'squared';
s.plot = 'mag';
subplot(211), freqzplot(H,w,s)
title('Rectangular and Hamming windowed LPF in squared magnitude');

s.yunits = 'db';
subplot(212), freqzplot(H,w,s)
title('Rectangular and Hamming windowed LPF in dB');