jens
1f5b0b0570
git-svn-id: http://moon:8086/svn/matlab/trunk@128 801c6759-fa7c-4059-a304-17956f83a07c
29 lines
575 B
Matlab
29 lines
575 B
Matlab
function [B,A] = boost(fs, fc, bw, gain, P);
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%BOOST - Design a boost filter at given gain, center
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% frequency fc, bandwidth bw, and sampling rate fs
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% (default = 1).
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%
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% J.O. Smith 11/28/02
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% Reference: Zolzer: Digital Audio Signal Processing, p. 124
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Q = fs/bw;
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wcT = 2*pi*fc/fs;
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K=tan(wcT/2);
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V=gain;
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b0 = 1 + V*K/Q + K^2;
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b1 = 2*(K^2 - 1);
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b2 = 1 - V*K/Q + K^2;
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a0 = 1 + K/Q + K^2;
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a1 = 2*(K^2 - 1);
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a2 = 1 - K/Q + K^2;
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A(1,:) = [a0 a1 a2] /a0;
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B(1,:) = [b0 b1 b2] /a0;
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if nargout==0
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freqz(B(1,:),A(1,:));
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title('Boost Frequency Response')
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end
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