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滤波器设计画廊

这个例子展示了如何用该方法设计各种FIR和IIR数字滤波器designfilt功能在信号处理工具箱®产品中。

图库是为您设计的,用于识别感兴趣的过滤器响应、查看代码并在您自己的项目中使用它。它包含了每个过滤器响应的示例designfilt.但是,请注意,这些只是为每种响应类型设计过滤器的几种可能方法。有关详细的规范集列表,请参阅信号处理工具箱文档。

除非另有说明,在这个例子中,所有频率单位都是赫兹,所有纹波和衰减值都是分贝。

低通FIR滤波器

平等设计

成就= 100;fstop = 150;Apass = 1;Astop = 65;Fs = 1 e3;d = designfilt (“lowpassfir”...'Passband职业',馈送,“StopbandFrequency”Fstop,...“PassbandRipple”apas,'stopbandattenuation'Astop,...“DesignMethod”“equiripple”“SampleRate”,fs);fvtool (d)

低通滤波器IIR滤波器

最大限度地平面设计

成就= 100;fstop = 150;apas = 0.5;Astop = 65;Fs = 1 e3;d = designfilt ('洛链'...'Passband职业',馈送,“StopbandFrequency”Fstop,...“PassbandRipple”apas,'stopbandattenuation'Astop,...“DesignMethod”'黄油'“SampleRate”,fs);fvtool (d)

通带和停机带的波纹

N = 8;成就= 100;apas = 0.5;Astop = 65;Fs = 1 e3;d = designfilt ('洛链'...“FilterOrder”N...'Passband职业',馈送,...“PassbandRipple”apas,'stopbandattenuation'Astop,...“SampleRate”,fs);fvtool (d)

高通的FIR滤波器

平等设计

Fstop = 350;成就= 400;Astop = 65;apas = 0.5;Fs = 1 e3;d = designfilt (“highpassfir”“StopbandFrequency”Fstop,...'Passband职业',馈送,'stopbandattenuation'Astop,...“PassbandRipple”apas,“SampleRate”Fs,“DesignMethod”“equiripple”);fvtool (d)

高通IIR过滤器

最大限度地平面设计

Fstop = 350;成就= 400;Astop = 65;apas = 0.5;Fs = 1 e3;d = designfilt (“highpassiir”“StopbandFrequency”,fstop,...'Passband职业',馈送,'stopbandattenuation'Astop,...“PassbandRipple”apas,“SampleRate”Fs,“DesignMethod”'黄油');fvtool (d)

通带和停机带的波纹

N = 8;成就= 400;Astop = 65;apas = 0.5;Fs = 1 e3;d = designfilt (“highpassiir”...“FilterOrder”N...'Passband职业',馈送,...'stopbandattenuation'Astop,“PassbandRipple”apas,...“SampleRate”,fs);fvtool (d)

带通FIR滤波器

平等设计

Fstop1 = 150;Fpass1 = 200;Fpass2 = 300;Fstop2 = 350;Astop1 = 65;apas = 0.5;Astop2 = 65;Fs = 1 e3;d = designfilt (“bandpassfir”...'stopbandfrequency1',fstop1,“PassbandFrequency1”Fpass1,...'passbandfrequency2''Fpass2,'stopbandfrequency2'Fstop2,...'stopbandattenuation1'Astop1,“PassbandRipple”,奥斯斯,...“StopbandAttenuation2”Astop2,...“DesignMethod”“equiripple”“SampleRate”,fs);fvtool (d)

不对称带衰减

N = 50;Fstop1 = 150;Fpass1 = 200;Fpass2 = 300;Fstop2 = 350;Wstop1 = 3;Wstop2 = 100;Fs = 1 e3;d = designfilt (“bandpassfir”...“FilterOrder”N...'stopbandfrequency1',fstop1,“PassbandFrequency1”Fpass1,...'passbandfrequency2''Fpass2,'stopbandfrequency2'Fstop2,...“StopbandWeight1”Wstop1,“StopbandWeight2”Wstop2,...“DesignMethod”“equiripple”“SampleRate”,fs);fvtool (d)

带通IIR过滤器

最大限度地平面设计

Fstop1 = 150;Fpass1 = 200;Fpass2 = 300;Fstop2 = 350;Astop1 = 65;apas = 0.5;Astop2 = 65;Fs = 1 e3;d = designfilt (“bandpassiir”...'stopbandfrequency1',fstop1,“PassbandFrequency1”Fpass1,...'passbandfrequency2''Fpass2,'stopbandfrequency2'Fstop2,...'stopbandattenuation1'Astop1,“PassbandRipple”,奥斯斯,...“StopbandAttenuation2”Astop2,...“DesignMethod”'黄油'“SampleRate”Fs);fvtool (d)

通带和停机带的波纹

N = 8;Fpass1 = 200;Fpass2 = 300;Astop1 = 65;apas = 0.5;Astop2 = 65;Fs = 1 e3;d = designfilt (“bandpassiir”...“FilterOrder”N...“PassbandFrequency1”Fpass1,'passbandfrequency2''Fpass2,...'stopbandattenuation1'Astop1,“PassbandRipple”,奥斯斯,...“StopbandAttenuation2”Astop2,...“SampleRate”Fs);fvtool (d)

Bandstop FIR滤波器

平等设计

Fpass1 = 100;Fstop1 = 150;Fstop2 = 350;Fpass2 = 400;Apass1 = 0.5;Astop = 65;Apass2 = 0.5;Fs = 1 e3;d = designfilt (“bandstopfir”...“PassbandFrequency1”Fpass1,'stopbandfrequency1',fstop1,...'stopbandfrequency2',fstop2,'passbandfrequency2''Fpass2,...“PassbandRipple1”Apass1,'stopbandattenuation'Astop,...“PassbandRipple2”Apass2,...“DesignMethod”“equiripple”“SampleRate”Fs);fvtool (d)

不对称通带涟漪

n = 30;Fpass1 = 100;Fstop1 = 150;Fstop2 = 350;Fpass2 = 400;wpass1 = 1;wpass2 = 10;Fs = 1 e3;d = designfilt (“bandstopfir”...“FilterOrder”N...“PassbandFrequency1”Fpass1,'stopbandfrequency1',fstop1,...'stopbandfrequency2',fstop2,'passbandfrequency2''Fpass2,...'passbandweight1'Wpass1,'passbandweight2'Wpass2,...“DesignMethod”“equiripple”“SampleRate”Fs);fvtool (d)

Bandstop IIR滤波器

最大限度地平面设计

Fpass1 = 100;Fstop1 = 150;Fstop2 = 350;Fpass2 = 400;Apass1 = 0.5;Astop = 65;Apass2 = 0.5;Fs = 1 e3;d = designfilt ('bandstopiir'...“PassbandFrequency1”Fpass1,'stopbandfrequency1',fstop1,...'stopbandfrequency2',fstop2,'passbandfrequency2''Fpass2,...“PassbandRipple1”Apass1,'stopbandattenuation'Astop,...“PassbandRipple2”Apass2,...“DesignMethod”'黄油'“SampleRate”Fs);fvtool (d)

通带和停机带的波纹

N = 8;fpass1 = 125;fpass2 = 375;apas = 0.5;Astop = 65;Fs = 1 e3;d = designfilt ('bandstopiir'...“FilterOrder”N...“PassbandFrequency1”Fpass1,'passbandfrequency2''Fpass2,...“PassbandRipple”apas,'stopbandattenuation',astop,...“SampleRate”,fs);fvtool (d)

任意幅度FIR滤波器

单波段任意幅值设计

N = 300;%频率为标准化单位F1 = 0:0.01:0.18;f2 = [.2 .38 .4 .55 .562 .585 .78];F3 = 0.79:0.01:1;freqvect = [f1 f2 f3];频率百分比向量用线性单位定义期望的响应A1 = .5 + SIN(2 * PI * 7.5 * F1)/ 4;%正弦部分A2 =[。5 . 2.3 . 1 1 -。2 -。2 1 1];%分段线性部分A3 = .2 + 18 *(1-F3)。^ 2;%二次部分AmpVect = [A1 A2 A3];d = designfilt (“arbmagfir”...“FilterOrder”N“振幅”,安瓿,'频率'FreqVect,...“DesignMethod”“freqsamp”);FVTool(D,“MagnitudeDisplay”“零”

多频带低通设计,在阻带上采用阶梯式衰减电平

n = 150;B = 2;频段数量%频率为标准化单位F1 = [0.25];%通频带F2 =[。3 .4 .401 .5 .501 .6 .601 .7 .701 .8 .801 .9 .901 1];%stopband.A1 = 1(大小(F1));1波段的期望振幅,以线性单位表示A2 = 0(大小(F2));线性单元中带2的%期望幅度%载体的重量W = 10。^([0 0 5 5 10 10 15 15 20 20 25 25 30 30 35 35]/20);W1 = W (1:2);% 1波段的权重w2 = w(3:结束);% 2波段的权重d = designfilt (“arbmagfir”...“FilterOrder”N'numbands'B...“BandFrequencies1”F1,“BandAmplitudes1”A1,...“BandFrequencies2”F2,“BandAmplitudes2”A2...'Bandweights1'W1,'bandweights2'W2);fvtool (d)

差异化因素FIR滤清器

全带设计

N = 41;Fs = 1 e3;d = designfilt (“differentiatorfir”...“FilterOrder”N“DesignMethod”“equiripple”“SampleRate”,fs);FVTool(D,“MagnitudeDisplay”“零”“OverlayedAnalysis”“阶段”

部分带设计

n = 40;成就= 100;fstop = 150;Fs = 1 e3;d = designfilt (“differentiatorfir”...“FilterOrder”N...'Passband职业',馈送,“StopbandFrequency”Fstop,...“DesignMethod”“equiripple”“SampleRate”,fs);FVTool(D,“MagnitudeDisplay”“零”“OverlayedAnalysis”“阶段”

希尔伯特FIR滤波器

平等设计

n = 40;tw = 50;Fs = 1 e3;d = designfilt (“hilbertfir”...“FilterOrder”N'transitionwidth'Tw,...“DesignMethod”“equiripple”“SampleRate”,fs);FVTool(D,“MagnitudeDisplay”“零”“OverlayedAnalysis”“阶段”