function output = myIIRLowpassBiquad(inp,num,den) %myIIRNotchBiquad Biquad低通滤波器实现%用作MATLAB定点转换器App示例的一部分。The MathWorks, Inc. persistent bqLPFilter版权所有;if isempty(bqLPFilter) bqLPFilter = dsp。BiquadFilter(…'SOSMatrixSource'，'输入端口'，…'ScaleValuesInputPort'， false，…“SectionInputDataType”，“自定义”，…'SectionOutputDataType'， '自定义'，…'NumeratorProductDataType'， 'Custom'，…'DenominatorProductDataType'， 'Custom'，…'NumeratorAccumulatorDataType'， 'Custom'，… 'DenominatorAccumulatorDataType', 'Custom', ... 'StateDataType', 'Custom', ... 'OutputDataType', 'Custom'); end output = bqLPFilter(inp, num, den); end

myIIRLowpassBiquad测试平台。The MathWorks, Inc. %%预先设计的滤波器(系数存储在MAT文件中):% f = design(fdesign.lowpass('Fp,Fst,Ap,Ast'，0.4,0.45,0.5,80)，…% 'ellip'， FilterStructure='df1sos'，SystemObject=true);% sosMatrix = f.SOSMatrix;% sclValues = f.ScaleValues;% b = repmat (sclValues (1: (end-1)), 1, 3)。* sosMatrix (:, (1:3));% a = sosMatrix(:，(5:6));% num = b';% den = a';% (myIIRLowpassBiquadDesign攒钱。Mat '， 'b'， 'a'， 'num'， 'den'); load('myIIRLowpassBiquadDesign.mat'); %% Interference signal, using values in range (-0.5, 0.5) Wo = 75/(300/2); % 75 Hz tone; system running at 300 Hz inp_len = 4000; sinTvec = (0:(inp_len-1))'; inp_itf = 0.5 .* sin((pi*Wo) .* sinTvec); %% Filtering and visualization % Filter an input signal, including an interference % tone, to see if the tone is successfully removed. rng(12345); % seed the rng for repeatable results scope = spectrumAnalyzer(SampleRate=300,... PlotAsTwoSidedSpectrum=false,ShowLegend=true,YLimits=[-125 25],... Title='Input Signal and Filter Output Signal', ... ChannelNames={'Input', 'Filter Output'}); for k = 1:10 inp_sig = rand(inp_len,1) - 0.5; % random values in range (-0.5, 0.5) inp = inp_sig + inp_itf; out_1 = myIIRLowpassBiquad(inp,num,den); % filter scope([inp,out_1]); % visualize end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % % % 由MATLAB 9.3和6.0定点设计师  % % % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %# codegen函数输出= myIIRLowpassBiquad_fixpt (inp, num窝)% myIIRNotchBiquad Biquad使用低通滤波器实现%的MATLAB定点转换器的应用例子。The MathWorks, Inc. fm = get_fimath();持久bqLPFilter;if isempty(bqLPFilter) bqLPFilter = dsp。BiquadFilter(…'SOSMatrixSource'， '输入端口'，…'ScaleValuesInputPort'， false，…“SectionInputDataType”，“自定义”，…'SectionOutputDataType'， '自定义'，…'NumeratorProductDataType'， 'Custom'，…'DenominatorProductDataType'， 'Custom'，… 'NumeratorAccumulatorDataType', 'Custom', ... 'DenominatorAccumulatorDataType', 'Custom', ... 'StateDataType', 'Custom', ... 'OutputDataType', 'Custom' , ... 'CustomSectionInputDataType', numerictype([], 16, 8), ... 'CustomSectionOutputDataType', numerictype([], 16, 8), ... 'CustomNumeratorProductDataType', numerictype([], 32, 26), ... 'CustomDenominatorProductDataType', numerictype([], 32, 23), ... 'CustomNumeratorAccumulatorDataType', numerictype([], 32, 24), ... 'CustomDenominatorAccumulatorDataType', numerictype([], 32, 23), ... 'CustomStateDataType', numerictype([], 16, 8), ... 'CustomOutputDataType', numerictype([], 16, 15)); end output = fi(bqLPFilter(inp, num, den), 1, 16, 15, fm); end function fm = get_fimath() fm = fimath('RoundingMethod', 'Floor',... 'OverflowAction', 'Wrap',... 'ProductMode','FullPrecision',... 'MaxProductWordLength', 128,... 'SumMode','FullPrecision',... 'MaxSumWordLength', 128); end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % 从项目”myIIRLowpassBiquad脚本生成。2014年10月16日。%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % 创建配置对象的类“coder.FixPtConfig”。%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% cfg = coder.config(“fixpt”);cfg。TestBenchName = {sprintf('S:\\Work\\15aFeatureExamples\\biquad_notch_f2f\\myIIRLowpassBiquad_tb.m')};cfg。DefaultWordLength = 16;cfg。logioforcomparisonplots = true;cfg。TestNumerics = true; %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Define argument types for entry-point 'myIIRLowpassBiquad'. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% ARGS = cell(1,1); ARGS{1} = cell(3,1); ARGS{1}{1} = coder.typeof(0,[4000 1]); ARGS{1}{2} = coder.typeof(0,[3 5]); ARGS{1}{3} = coder.typeof(0,[2 5]); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Invoke MATLAB Coder. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% codegen -float2fixed cfg myIIRLowpassBiquad -args ARGS{1}