interpol2.m

用于模拟时变非平稳的ARMA过程

function y= interpol2(x)
% function y= interpol2(x)
%   This file is part of the TFPM toolbox v1.0 (c)
%   [e-mail] and underlies the GPL.
% 
% Interpolates x by 2, filtering?

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if(0)% TEST TEST TEST TEST TEST TEST TEST TEST TEST TEST
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clear;tfpm;
N    = 128;
x= sin(20*pi/N*(0:N-1));
%x= randn(N, 1);
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end;% TEST TEST TEST TEST TEST TEST TEST TEST TEST TEST
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N= length(x);
y1= zeros(2*N, 1);
y1(1:2:end)= x;
[B, A] = butter(5, .5);
y= 2*filter(B, A, y1);

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if(0)% TEST TEST TEST TEST TEST TEST TEST TEST TEST TEST
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clear;tfpm;
N= 256;
x= sin(2*pi/N*(0:N-1))';
x= randn(N, 1);
KK= 10

figure(1);
yold= x;
for k= 1:KK
   ynew= interpol2(yold);
   subplot(KK, 1, k)
   plot(ynew);axis([0 (2^k)*N, -2 2]);drawnow
   yold= ynew;
end;
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end;% TEST TEST TEST TEST TEST TEST TEST TEST TEST TEST
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