Nucleo-F446 による遮断周波数可変 LPF/HPF .DA変換器にデータを送る際は 4 倍にアップ・サンプリング.
Dependencies: mbed SerialTxRxIntr F446_AD_DA_MultirateSWI
IIR_Design/BilinearDesignLH.hpp@8:da8bdc49f7ad, 2019-06-30 (annotated)
- Committer:
- MikamiUitOpen
- Date:
- Sun Jun 30 02:21:43 2019 +0000
- Revision:
- 8:da8bdc49f7ad
- Parent:
- 0:89d173001e82
8
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
MikamiUitOpen | 0:89d173001e82 | 1 | //------------------------------------------------------------------------ |
MikamiUitOpen | 0:89d173001e82 | 2 | // 双一次z変換によるバタワースフィルタの設計(ヘッダ) |
MikamiUitOpen | 0:89d173001e82 | 3 | // LPF, HPF のみ |
MikamiUitOpen | 0:89d173001e82 | 4 | // |
MikamiUitOpen | 0:89d173001e82 | 5 | // 2018/05/14, Copyright (c) 2018 MIKAMI, Naoki |
MikamiUitOpen | 0:89d173001e82 | 6 | //------------------------------------------------------------------------ |
MikamiUitOpen | 0:89d173001e82 | 7 | |
MikamiUitOpen | 0:89d173001e82 | 8 | #ifndef BILINEAR_BUTTERWORTH_HPP |
MikamiUitOpen | 0:89d173001e82 | 9 | #define BILINEAR_BUTTERWORTH_HPP |
MikamiUitOpen | 0:89d173001e82 | 10 | |
MikamiUitOpen | 0:89d173001e82 | 11 | #include "mbed.h" |
MikamiUitOpen | 0:89d173001e82 | 12 | #include <complex> // requisite |
MikamiUitOpen | 0:89d173001e82 | 13 | #include "Array.hpp" |
MikamiUitOpen | 0:89d173001e82 | 14 | #include "Biquad.hpp" |
MikamiUitOpen | 0:89d173001e82 | 15 | |
MikamiUitOpen | 0:89d173001e82 | 16 | namespace Mikami |
MikamiUitOpen | 0:89d173001e82 | 17 | { |
MikamiUitOpen | 0:89d173001e82 | 18 | typedef complex<float> Complex; // "Complex" を定義する |
MikamiUitOpen | 0:89d173001e82 | 19 | |
MikamiUitOpen | 0:89d173001e82 | 20 | class BilinearDesign |
MikamiUitOpen | 0:89d173001e82 | 21 | { |
MikamiUitOpen | 0:89d173001e82 | 22 | public: |
MikamiUitOpen | 0:89d173001e82 | 23 | enum Type { LPF, HPF }; |
MikamiUitOpen | 0:89d173001e82 | 24 | |
MikamiUitOpen | 0:89d173001e82 | 25 | // コンストラクタ |
MikamiUitOpen | 0:89d173001e82 | 26 | BilinearDesign(int order, float fs) |
MikamiUitOpen | 0:89d173001e82 | 27 | : PI_FS_(PI_/fs), ORDER_(order), |
MikamiUitOpen | 0:89d173001e82 | 28 | sP_(order/2), zP_(order/2), ck_(order/2) {} |
MikamiUitOpen | 0:89d173001e82 | 29 | |
MikamiUitOpen | 0:89d173001e82 | 30 | // デストラクタ |
MikamiUitOpen | 0:89d173001e82 | 31 | virtual ~BilinearDesign() {} |
MikamiUitOpen | 0:89d173001e82 | 32 | |
MikamiUitOpen | 0:89d173001e82 | 33 | // 設計の実行 |
MikamiUitOpen | 0:89d173001e82 | 34 | void Execute(float fc, Type pb, Biquad::Coefs c[], float& g); |
MikamiUitOpen | 0:89d173001e82 | 35 | |
MikamiUitOpen | 0:89d173001e82 | 36 | private: |
MikamiUitOpen | 0:89d173001e82 | 37 | static const float PI_ = 3.1415926536f; |
MikamiUitOpen | 0:89d173001e82 | 38 | const float PI_FS_; |
MikamiUitOpen | 0:89d173001e82 | 39 | const int ORDER_; |
MikamiUitOpen | 0:89d173001e82 | 40 | |
MikamiUitOpen | 0:89d173001e82 | 41 | Array<Complex> sP_; // s 平面上の極 |
MikamiUitOpen | 0:89d173001e82 | 42 | Array<Complex> zP_; // z 平面上の極 |
MikamiUitOpen | 0:89d173001e82 | 43 | Array<Biquad::Coefs> ck_; // Biquad構造の部分の係数 |
MikamiUitOpen | 0:89d173001e82 | 44 | float gain_; // 利得定数 |
MikamiUitOpen | 0:89d173001e82 | 45 | |
MikamiUitOpen | 0:89d173001e82 | 46 | void Butterworth(); |
MikamiUitOpen | 0:89d173001e82 | 47 | void Bilinear(float fc); |
MikamiUitOpen | 0:89d173001e82 | 48 | void ToCascade(Type pb); |
MikamiUitOpen | 0:89d173001e82 | 49 | void GetGain(Type pb); |
MikamiUitOpen | 0:89d173001e82 | 50 | void GetCoefs(Biquad::Coefs c[], float& gain); |
MikamiUitOpen | 0:89d173001e82 | 51 | }; |
MikamiUitOpen | 0:89d173001e82 | 52 | } |
MikamiUitOpen | 0:89d173001e82 | 53 | #endif // BILINEAR_BUTTERWORTH_HPP |