error_plot.m

用dsp解压mp3程序的算法

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% error_plot.m - Program for plotting error signal in exmp9_5.m
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x  = 0.1*randn(1,640); % normally distributed random numbers
b  = fir1(31,0.3);     % an FIR system as a unknown system
d  = filter(b,1,x);    % generated desired signal d(n)
w0 = zeros(1,32);      % intialize coefficient vector w(0) to 0
mu = 0.75;             % step size mu for the LMS algorithjm
s  = initlms(w0,mu);   % initialize w(0) and step size mu
[y,e,s] = adaptlms(x,d,s); % adaptive filtering
figure;
n = [1:640]; plot(n,e);% plot error signal e(n)
axis([1 640 -inf inf]);
xlabel('Time index n'); ylabel('Amplitude');
title('Convergence of error signal e(n)');