1. 首先设计低通滤波器
![](https://img-my.csdn.net/uploads/201303/20/1363779646_1992.jpg)
在simulink里面仿真
![](https://img-my.csdn.net/uploads/201303/20/1363779986_5336.jpg)
![](https://img-my.csdn.net/uploads/201303/20/1363779996_6566.jpg)
得到滤波器系数,并生成头文件:
![](https://img-my.csdn.net/uploads/201303/20/1363779956_6754.jpg)
解得差分方程
acc_xxx(index)=-IIR_A(2)*acc_xxx(index-1)-IIR_A(3)*acc_xxx(index-2)-IIR_A(4)*acc_xxx(index-3);
acc_xxx(index)=acc_xxx(index)+IIR_B(1)*acc_x(index)+IIR_B(2)*acc_x(index-1)+IIR_B(3)*acc_x(index-2)+IIR_B(4)*acc_x(index-3);
编写程序: