jens
579c1544b1
git-svn-id: http://moon:8086/svn/matlab/trunk@157 801c6759-fa7c-4059-a304-17956f83a07c
38 lines
823 B
Matlab
Executable File
38 lines
823 B
Matlab
Executable File
function [w, idx] = wkaiser(n, b)
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% function [w, idx] = wkaiser(n, b)
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k1 = 1.0/besselizero(b);
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k2 = 1 - mod(n, 2);
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ende = fix((n + 1)/2);
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idx = zeros(n, 1);
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% Calculate window coefficients
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for k=0:ende-1,
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tmp = (2*k + k2) / (n - 1.0);
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tmp2 = k1 * besselizero(b*sqrt(1.0 - tmp*tmp));
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mm = ende-(mod(not(k2), 2))+k+1;
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nn = ende-k;
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w(mm) = tmp2;
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w(nn) = tmp2;
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idx(nn) = idx(nn) + 1;
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idx(mm) = idx(mm) + 1;
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end;
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function sum = besselizero(x)
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BIZ_EPSILON = 1E-21; % Max error acceptable
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sum = 1.0;
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u = 1.0;
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halfx = x/2.0;
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n = 1;
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while(1)
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temp = halfx/n;
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u = u * temp * temp;
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sum = sum + u;
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n = n + 1;
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if (u < (BIZ_EPSILON * sum))
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break;
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end;
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end;
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