butter_biquad.m

来自「DSP中巴特沃思滤波器的设计使用Verilog编写.」· M 代码 · 共 22 行

function y=butter_biquad(SecOrd, Inp);

w=zeros(1,min(length(Inp),300));
w_tmp=w;
y=zeros(1,min(length(Inp),300));
x=Inp; %* 2^4;
SecOrd_scaled = round( SecOrd * 2^10); 
b1 = SecOrd_scaled(5);
b2 = SecOrd_scaled(6);


for n=3:min(length(Inp),300)
    w_tmp(n) = ( b1 * w(n-1) ) + ( b2 * w(n-2) );
    w(n) =  x(n) - ( w_tmp(n) / 2^10 );
    y(n) =  w(n)  + ( 2 * w(n-1) ) + ( w(n-2) );
end