Chapter003_TRobot
Dependencies: F746_GUI Array_Matrix TS_DISCO_F746NG mbed LCD_DISCO_F746NG BSP_DISCO_F746NG SDFileSystem_Warning_Fixed FrequencyResponseDrawer F746_SAI_IO
MyClasses_Functions/Biquad.hpp@12:fde5056cec5c, 2019-04-01 (annotated)
- Committer:
- SanYune
- Date:
- Mon Apr 01 06:43:07 2019 +0000
- Revision:
- 12:fde5056cec5c
- Parent:
- 0:04b43b777fae
Chapter003_TRobot
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
MikamiUitOpen | 0:04b43b777fae | 1 | //-------------------------------------------------------------- |
MikamiUitOpen | 0:04b43b777fae | 2 | // 縦続形 IIR フィルタで使う 1D タイプの 2 次のフィルタ |
MikamiUitOpen | 0:04b43b777fae | 3 | // Biquad filter of 1D type for IIR filter of cascade structure |
MikamiUitOpen | 0:04b43b777fae | 4 | // このクラスでは,係数は実行中に書き換えられることを想定している |
MikamiUitOpen | 0:04b43b777fae | 5 | // |
MikamiUitOpen | 0:04b43b777fae | 6 | // u[n] = x[n] + a1*u[n-1] + a2*u[n-2] |
MikamiUitOpen | 0:04b43b777fae | 7 | // y[n] = u[n] + b1*u[n-1] + b2*u[n-2] |
MikamiUitOpen | 0:04b43b777fae | 8 | // x[n] : input signal |
MikamiUitOpen | 0:04b43b777fae | 9 | // y[n] : output signal |
MikamiUitOpen | 0:04b43b777fae | 10 | // b0 = 1 |
MikamiUitOpen | 0:04b43b777fae | 11 | // |
MikamiUitOpen | 0:04b43b777fae | 12 | // 2016/03/25, Copyright (c) 2016 MIKAMI, Naoki |
MikamiUitOpen | 0:04b43b777fae | 13 | //-------------------------------------------------------------- |
MikamiUitOpen | 0:04b43b777fae | 14 | |
MikamiUitOpen | 0:04b43b777fae | 15 | #ifndef IIR_BIQUAD_HPP |
MikamiUitOpen | 0:04b43b777fae | 16 | #define IIR_BIQUAD_HPP |
MikamiUitOpen | 0:04b43b777fae | 17 | |
MikamiUitOpen | 0:04b43b777fae | 18 | #include "mbed.h" |
MikamiUitOpen | 0:04b43b777fae | 19 | |
MikamiUitOpen | 0:04b43b777fae | 20 | // 2nd order IIR filter |
MikamiUitOpen | 0:04b43b777fae | 21 | namespace Mikami |
MikamiUitOpen | 0:04b43b777fae | 22 | { |
MikamiUitOpen | 0:04b43b777fae | 23 | class Biquad |
MikamiUitOpen | 0:04b43b777fae | 24 | { |
MikamiUitOpen | 0:04b43b777fae | 25 | public: |
MikamiUitOpen | 0:04b43b777fae | 26 | struct Coefs { float a1, a2, b1, b2; }; |
MikamiUitOpen | 0:04b43b777fae | 27 | |
MikamiUitOpen | 0:04b43b777fae | 28 | Biquad() {} // Default constructore |
MikamiUitOpen | 0:04b43b777fae | 29 | |
MikamiUitOpen | 0:04b43b777fae | 30 | Biquad(const Coefs ck) |
MikamiUitOpen | 0:04b43b777fae | 31 | { |
MikamiUitOpen | 0:04b43b777fae | 32 | SetCoefficients(ck); |
MikamiUitOpen | 0:04b43b777fae | 33 | Clear(); |
MikamiUitOpen | 0:04b43b777fae | 34 | } |
MikamiUitOpen | 0:04b43b777fae | 35 | |
MikamiUitOpen | 0:04b43b777fae | 36 | void SetCoefficients(const Coefs ck) |
MikamiUitOpen | 0:04b43b777fae | 37 | { |
MikamiUitOpen | 0:04b43b777fae | 38 | a1_ = ck.a1; |
MikamiUitOpen | 0:04b43b777fae | 39 | a2_ = ck.a2; |
MikamiUitOpen | 0:04b43b777fae | 40 | b1_ = ck.b1; |
MikamiUitOpen | 0:04b43b777fae | 41 | b2_ = ck.b2; |
MikamiUitOpen | 0:04b43b777fae | 42 | } |
MikamiUitOpen | 0:04b43b777fae | 43 | |
MikamiUitOpen | 0:04b43b777fae | 44 | float Execute(float xn) |
MikamiUitOpen | 0:04b43b777fae | 45 | { |
MikamiUitOpen | 0:04b43b777fae | 46 | float un = xn + a1_*un1_ + a2_*un2_; |
MikamiUitOpen | 0:04b43b777fae | 47 | float yn = un + b1_*un1_ + b2_*un2_; |
MikamiUitOpen | 0:04b43b777fae | 48 | |
MikamiUitOpen | 0:04b43b777fae | 49 | un2_ = un1_; |
MikamiUitOpen | 0:04b43b777fae | 50 | un1_ = un; |
MikamiUitOpen | 0:04b43b777fae | 51 | |
MikamiUitOpen | 0:04b43b777fae | 52 | return yn; |
MikamiUitOpen | 0:04b43b777fae | 53 | } |
MikamiUitOpen | 0:04b43b777fae | 54 | |
MikamiUitOpen | 0:04b43b777fae | 55 | void Clear() { un1_ = un2_ = 0; } |
MikamiUitOpen | 0:04b43b777fae | 56 | |
MikamiUitOpen | 0:04b43b777fae | 57 | private: |
MikamiUitOpen | 0:04b43b777fae | 58 | float a1_, a2_, b1_, b2_; |
MikamiUitOpen | 0:04b43b777fae | 59 | float un1_, un2_; |
MikamiUitOpen | 0:04b43b777fae | 60 | |
MikamiUitOpen | 0:04b43b777fae | 61 | // disallow copy constructor |
MikamiUitOpen | 0:04b43b777fae | 62 | Biquad(const Biquad&); |
MikamiUitOpen | 0:04b43b777fae | 63 | }; |
MikamiUitOpen | 0:04b43b777fae | 64 | } |
MikamiUitOpen | 0:04b43b777fae | 65 | #endif // IIR_BIQUAD_HPP |