一阶 RC 低通滤波器的电路如下图所示;2 simulink 仿真这里直接根据公式③构建一搞Subsystem;Subsystem整体的仿真图如下:其中Sine Wave频率设置为2*pi*50其中Sine Wave1频率设置为2*pi所以这里需要使得2*pi*50的信号衰减,所以根据,截止频率的计算公式,可以改变增益的值,具体如下所示;3 simulink 运行结果最终的仿真的运行结果如下图所示;Gain Value为0.005Gain Value为0.03184 matlab 实现根据公式实现数字一阶 RC 低通滤波器,具体 matlab 程序如下;Serial = 0:0.1:100;Fs = 1;Phase = 0;Amp = 1;% 高频信号N0 = 2*pi*Fs*Serial - Phase;X0 = Amp*sin(N);subplot(4,1,1);plot(X0);% 低频信号Fs = 0.02;N1 = 2*pi*Fs*Serial - Phase;X1 = Amp*sin(N1);subplot(4,1,2);plot(X1);% 高频低频叠加的信号X2=X0+X1;subplot(4,1,3);plot(X2);%Xi-Yi=RC*(Yi - Yi-1)/DetalTlen = length(X2);X3=X2;p=0.05;% 一阶 RC 滤波得到 X3for i=2:len X3(i) = p*X2(i)+(1-p)*X3(i-1);endsubplot(4,1,4);plot(X3);5 matlab 运行结果运行结果如下所示;6 C 语言实现low_filter.htypedef struct{ int16_t Input; int16_t Output[2]; int32_t FilterTf; int32_t FilterTs; int32_t Kr; int32_t Ky; } low_filter;void low_filter_init(low_filter *v);int16_t low_filter_calc(low_filter *v);其中;FilterTs为采样时间;FilterTf为RC时间常数具体参考下图;low_filter.cvoid low_filter_init(low_filter *v){ v->Kr = v->FilterTs*1024/(v->FilterTs + v->FilterTf); v->Ky = v->FilterTf*1024/(v->FilterTs + v->FilterTf);}int16_t low_filter_calc(low_filter *v){ int32_t tmp = 0; tmp = ((int32_t)v->Kr*v->Input + v->Ky*v->Output[1])/1024; if(tmp>32767){ tmp = 32767; } if( tmp < -32768){ tmp = -32768; } v->Output[0] = (int16_t)tmp; v->Output[1] = v->Output[0]; return v->Output[0];}7 C 语言运行结果实际测试结果;
欢迎分享,转载请注明来源:内存溢出
评论列表(0条)