CQ出版社セミナ,2021/12/07開催「実習・C++言語によるArmマイコンのプログラミング」で使うプログラム.
Dependencies: Array_Matrix mbed SerialTxRxIntr UIT_FFT_Real
IIR_Filter/Biquad.hpp@5:5e55a5f440c0, 2020-04-02 (annotated)
- Committer:
- MikamiUitOpen
- Date:
- Thu Apr 02 01:12:34 2020 +0000
- Revision:
- 5:5e55a5f440c0
- Parent:
- 0:a80f730d32a8
6
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
MikamiUitOpen | 0:a80f730d32a8 | 1 | //-------------------------------------------------------------- |
MikamiUitOpen | 0:a80f730d32a8 | 2 | // 縦続形 IIR フィルタの構成要素として使う 2 次の IIR フィルタ |
MikamiUitOpen | 0:a80f730d32a8 | 3 | // b0 は 1 と仮定している |
MikamiUitOpen | 0:a80f730d32a8 | 4 | // |
MikamiUitOpen | 0:a80f730d32a8 | 5 | // u[n] = x[n] + a1*u[n-1] + a2*u[n-2] |
MikamiUitOpen | 0:a80f730d32a8 | 6 | // y[n] = u[n] + b1*u[n-1] + b2*u[n-2] |
MikamiUitOpen | 0:a80f730d32a8 | 7 | // |
MikamiUitOpen | 0:a80f730d32a8 | 8 | // 2019/11/22, Copyright (c) 2019 MIKAMI, Naoki |
MikamiUitOpen | 0:a80f730d32a8 | 9 | //-------------------------------------------------------------- |
MikamiUitOpen | 0:a80f730d32a8 | 10 | |
MikamiUitOpen | 0:a80f730d32a8 | 11 | #ifndef IIR_BIQUAD_HPP |
MikamiUitOpen | 0:a80f730d32a8 | 12 | #define IIR_BIQUAD_HPP |
MikamiUitOpen | 0:a80f730d32a8 | 13 | |
MikamiUitOpen | 0:a80f730d32a8 | 14 | #include "mbed.h" |
MikamiUitOpen | 0:a80f730d32a8 | 15 | |
MikamiUitOpen | 0:a80f730d32a8 | 16 | // 2 次の IIR フィルタ |
MikamiUitOpen | 0:a80f730d32a8 | 17 | class Biquad |
MikamiUitOpen | 0:a80f730d32a8 | 18 | { |
MikamiUitOpen | 0:a80f730d32a8 | 19 | public: |
MikamiUitOpen | 0:a80f730d32a8 | 20 | // デフォルト・コンストラクタ |
MikamiUitOpen | 0:a80f730d32a8 | 21 | Biquad() {} |
MikamiUitOpen | 0:a80f730d32a8 | 22 | |
MikamiUitOpen | 0:a80f730d32a8 | 23 | // 係数を個別に与えるコンストラクタ |
MikamiUitOpen | 0:a80f730d32a8 | 24 | Biquad(float a1, float a2, float b1, float b2) |
MikamiUitOpen | 0:a80f730d32a8 | 25 | : a1_(a1), a2_(a2), b1_(b1), b2_(b2), un1_(0), un2_(0) {} |
MikamiUitOpen | 0:a80f730d32a8 | 26 | |
MikamiUitOpen | 0:a80f730d32a8 | 27 | // 2 次のフィルタを実行する |
MikamiUitOpen | 0:a80f730d32a8 | 28 | float Execute(float xn) |
MikamiUitOpen | 0:a80f730d32a8 | 29 | { |
MikamiUitOpen | 0:a80f730d32a8 | 30 | float un = xn + a1_*un1_ + a2_*un2_; |
MikamiUitOpen | 0:a80f730d32a8 | 31 | float yn = un + b1_*un1_ + b2_*un2_; |
MikamiUitOpen | 0:a80f730d32a8 | 32 | |
MikamiUitOpen | 0:a80f730d32a8 | 33 | un2_ = un1_; |
MikamiUitOpen | 0:a80f730d32a8 | 34 | un1_ = un; |
MikamiUitOpen | 0:a80f730d32a8 | 35 | |
MikamiUitOpen | 0:a80f730d32a8 | 36 | return yn; |
MikamiUitOpen | 0:a80f730d32a8 | 37 | } |
MikamiUitOpen | 0:a80f730d32a8 | 38 | |
MikamiUitOpen | 0:a80f730d32a8 | 39 | private: |
MikamiUitOpen | 0:a80f730d32a8 | 40 | float a1_, a2_, b1_, b2_; |
MikamiUitOpen | 0:a80f730d32a8 | 41 | float un1_, un2_; |
MikamiUitOpen | 0:a80f730d32a8 | 42 | |
MikamiUitOpen | 0:a80f730d32a8 | 43 | // コピー・コンストラクタ禁止 |
MikamiUitOpen | 0:a80f730d32a8 | 44 | Biquad(const Biquad&); |
MikamiUitOpen | 0:a80f730d32a8 | 45 | }; |
MikamiUitOpen | 0:a80f730d32a8 | 46 | |
MikamiUitOpen | 0:a80f730d32a8 | 47 | #endif // IIR_BIQUAD_HPP |
MikamiUitOpen | 0:a80f730d32a8 | 48 | |
MikamiUitOpen | 0:a80f730d32a8 | 49 |