一种去掉偶尔产生不规则极端数值点的滤波方法

1，matlab代码

close all;clc;

clear all;

st=200:-4:1;%采集150个数据，每次减1

st=zeros(1,200)+10;%采集150个数据，每次减1

%y = awgn(x,SNR,SIGPOWER)信噪比SNR以dB为单位；如果SIGPOWER是数值，则其代表以dBW为单位的信号强度；如果SIGPOWER为'measured'，则函数将在加入噪声之前测定信号强度

St_noise=awgn(st,10,'measured');

figure;plot(st);hold on;

plot(St_noise);hold off;

 

% #define NZEROS 2

% #define NPOLES 2

GAIN=1.804169259e+02;%GAIN=180;

 

xv=zeros(1,3);

yv=zeros(1,3);

 

for i=1:length(St_noise)

xv(1)=xv(2);

xv(2) = xv(3);

xv(3)=St_noise(i)/GAIN;

 

disp(xv(2));

disp(xv(3));

yv(1)=yv(2);

yv(2) = yv(3);

yv(3)=(xv(1) + xv(3)) + 2 * xv(2) + ( -0.8008026467 * yv(1)) + ( 1.7786317778 * yv(2));

St_iir(i)= yv(3);

end

figure;plot(st);hold on;

plot(St_iir(1:length(St_iir)));hold off;

2，C语言写法

#define NZEROS 2

#define NPOLES 2

#define GAIN 1.804169259e+02

static float xv[NZEROS+1], yv[NPOLES+1];

static void filterloop()

{

for (;;)

{

xv[0] = xv[1];

xv[1] = xv[2];

xv[2] = next input value / GAIN;

yv[0] = yv[1];

yv[1] = yv[2];

yv[2] = (xv[0] + xv[2]) + 2 * xv[1]+ ( -0.8008026467 * yv[0]) + ( 1.7786317778 * yv[1]);

next output value = yv[2];

}

}