myIIRNotchBiquad Biquad低通滤波器实现%用作MATLAB定点转换器应用程序示例的一部分。% Copyright 2016 The MathWorks, Inc. persistent bqLPFilter;if isempty(bqLPFilter) bqLPFilter = dsp. if isempty(bqLPFilter)BiquadFilter(…'SOSMatrixSource'， 'Input port'，…“ScaleValuesInputPort”,假的,…“SectionInputDataType”,“自定义”,…“SectionOutputDataType”,“自定义”,…“NumeratorProductDataType”,“自定义”,…“DenominatorProductDataType”,“自定义”,…“NumeratorAccumulatorDataType”,“自定义”,… 'DenominatorAccumulatorDataType', 'Custom', ... 'StateDataType', 'Custom', ... 'OutputDataType', 'Custom'); end output = bqLPFilter(inp, num, den); end

%% myIIRLowpassBiquad测试台。预设计滤波器(系数存储在MAT文件):% f = design(fdesign.lowpass('Fp,Fst,Ap,Ast'，0.4,0.45,0.5,80)，…% 'ellip'， 'FilterStructure'， 'df1sos'，'SystemObject'，true);% sosMatrix = f.s 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 = dsp.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和定点设计器6.0%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%codegen函数输出=myIIRLowpassBiquad fixpt（inp，num，den）%myIIRNotchBiquad低通滤波器实现%用作MATLAB定点转换器应用程序示例的一部分。%版权所有2016 The MathWorks，Inc.fm=get_fimath（）；持久性bqLPFilter；如果isempty（bqLPFilter）bqLPFilter=dsp.BiquadFilter（…'SOSMatrixSource'，'Input port'，'ScaleValuesInputPort'，false，…'SectionInputDataType'，'Custom'，'SectionOutputDataType'，'Custom'，'NumeratorProductDataType'，'Custom'，'DenominorProductDataType'，'Custom'，'NumeratorAccumeratorDataType'，'Custom'，'DenominorAccumeratorDataType'，'Custom StateDataType'，'“，”自定义“，…”OutputDataType“，”自定义“，”CustomSectionInputDataType“，”numerictype（[]，16，8）、”CustomSectionOutputDataType“，”numerictype（[]，16，8）、”CustomNumeratorProductDataType“，”numerictype（[]，32，26）、”CustomDenominatorProductDataType“，”numerictype（[]，32，23）、”CustomNumeratorAccumeratorDataType（[]，32，24），'CustomDenominorAccumulatorDataType'，numerictype（[]，32，23），'CustomStateDataType'，numerictype（[]，16，8），'CustomOutputDataType'，numerictype（[]，16，15））；end output=fi（bqLPFilter（inp，num，den），1，16，15，fm）；end函数fm=get_fimath（）fm=fimath（“RoundingMethod”、“Floor”、“OverflowAction”、“Wrap”、“ProductMode”、“FullPrecision”、“MaxProductWordLength”、“128”、“SumMode”、“FullPrecision”、“MaxSumWordLength”、“128”）；结束

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % 从项目”myIIRLowpassBiquad脚本生成。撮合下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。LogIOForComparisonPlotting = 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}