44 lines
1.3 KiB
Matlab
44 lines
1.3 KiB
Matlab
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clear all;
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close all;
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interp_rate = 50000;
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h_cic = dsp.CICInterpolator('InterpolationFactor', interp_rate, 'NumSections',6 );%, ...
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%'FixedPointDataType','Specify word and fraction lengths', ...
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%'SectionWordLengths', [12 20 28 35 43 51], ...
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%'SectionFractionLengths', [11 11 11 11 11 11], ...
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%'OutputWordLength', 12, ...
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%'OutputFractionLength', 11);
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gainCIC = (h_cic.InterpolationFactor*h_cic.DifferentialDelay)^h_cic.NumSections
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[h1, w1] = h_cic.freqz();
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fs = 1;
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fPass = 0.20;
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fStop = 0.50;
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ast = 70;
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prip = 0.05;
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CICCompInterp = dsp.CICCompensationInterpolator(h_cic, ...
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'InterpolationFactor',2,'PassbandFrequency',fPass, ...
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'StopbandFrequency',fStop,'StopbandAttenuation',ast, ...
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'SampleRate',fs);
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[h2, w2] = CICCompInterp.freqz();
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CICCompInterp.coeffs()
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FC = dsp.FilterCascade(CICCompInterp, h_cic);
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[h3, w3] = FC.freqz();
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subplot(211); hold on;
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plot(w1/pi, 20*log10(abs(h1)/gainCIC));
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plot(w2/pi, 20*log10(abs(h2)));
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hold off; grid
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subplot(212); plot(w3/pi, 20*log10(abs(h3)/gainCIC/sum(CICCompInterp.coeffs().Numerator))); grid
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nt = numerictype(1,16,15);
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fdhdltool(CICCompInterp, nt);
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nt = numerictype(1,36,30);
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fdhdltool(h_cic,nt);
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