不韋 呂
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SDR_AM_Rx_CIC
AM中波放送用SDR.CICフィルタのみを使用.CQ出版社「トランジスタ技術」誌,2021年4月号に掲載
SDR_Library/IirDcCut.hpp@1:30d9fb51dec1, 2019-09-23 (annotated)
- Committer:
- MikamiUitOpen
- Date:
- Mon Sep 23 07:32:10 2019 +0000
- Revision:
- 1:30d9fb51dec1
- Child:
- 2:4bec6b2be809
2
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
MikamiUitOpen | 1:30d9fb51dec1 | 1 | //----------------------------------------------------------------- |
MikamiUitOpen | 1:30d9fb51dec1 | 2 | // 直流分除去用 IIR フィルタ |
MikamiUitOpen | 1:30d9fb51dec1 | 3 | // u[n] = a1*u[n-1] + x[n] |
MikamiUitOpen | 1:30d9fb51dec1 | 4 | // y[n] = g0*(u[n] - u[n-1]) |
MikamiUitOpen | 1:30d9fb51dec1 | 5 | // |
MikamiUitOpen | 1:30d9fb51dec1 | 6 | // 2019/09/21, Copyright (c) 2019 MIKAMI, Naoki |
MikamiUitOpen | 1:30d9fb51dec1 | 7 | //----------------------------------------------------------------- |
MikamiUitOpen | 1:30d9fb51dec1 | 8 | |
MikamiUitOpen | 1:30d9fb51dec1 | 9 | #include "mbed.h" |
MikamiUitOpen | 1:30d9fb51dec1 | 10 | |
MikamiUitOpen | 1:30d9fb51dec1 | 11 | #ifndef IIR_DC_CUT_HPP |
MikamiUitOpen | 1:30d9fb51dec1 | 12 | #define IIR_DC_CUT_HPP |
MikamiUitOpen | 1:30d9fb51dec1 | 13 | namespace Mikami |
MikamiUitOpen | 1:30d9fb51dec1 | 14 | { |
MikamiUitOpen | 1:30d9fb51dec1 | 15 | class IirDcCut |
MikamiUitOpen | 1:30d9fb51dec1 | 16 | { |
MikamiUitOpen | 1:30d9fb51dec1 | 17 | public: |
MikamiUitOpen | 1:30d9fb51dec1 | 18 | // コンストラクタ |
MikamiUitOpen | 1:30d9fb51dec1 | 19 | // a1 フィルタの係数 |
MikamiUitOpen | 1:30d9fb51dec1 | 20 | // g0 利得定数 |
MikamiUitOpen | 1:30d9fb51dec1 | 21 | IirDcCut(float a1, float g0) |
MikamiUitOpen | 1:30d9fb51dec1 | 22 | : A1_(a1), G0_(g0) { un1_ = 0; } |
MikamiUitOpen | 1:30d9fb51dec1 | 23 | |
MikamiUitOpen | 1:30d9fb51dec1 | 24 | // フィルタの実行 |
MikamiUitOpen | 1:30d9fb51dec1 | 25 | float Execute(float xn) |
MikamiUitOpen | 1:30d9fb51dec1 | 26 | { |
MikamiUitOpen | 1:30d9fb51dec1 | 27 | float un = A1_*un1_ + xn; |
MikamiUitOpen | 1:30d9fb51dec1 | 28 | float yn = (un - un1_)*G0_; |
MikamiUitOpen | 1:30d9fb51dec1 | 29 | un1_ = un; |
MikamiUitOpen | 1:30d9fb51dec1 | 30 | return yn; |
MikamiUitOpen | 1:30d9fb51dec1 | 31 | } |
MikamiUitOpen | 1:30d9fb51dec1 | 32 | |
MikamiUitOpen | 1:30d9fb51dec1 | 33 | private: |
MikamiUitOpen | 1:30d9fb51dec1 | 34 | const float A1_; // フィルタ係数 |
MikamiUitOpen | 1:30d9fb51dec1 | 35 | const float G0_; // 利得定数 |
MikamiUitOpen | 1:30d9fb51dec1 | 36 | float un1_; // 中間の値 |
MikamiUitOpen | 1:30d9fb51dec1 | 37 | |
MikamiUitOpen | 1:30d9fb51dec1 | 38 | // コピー・コンストラクタ禁止のため |
MikamiUitOpen | 1:30d9fb51dec1 | 39 | IirDcCut(const IirDcCut&); |
MikamiUitOpen | 1:30d9fb51dec1 | 40 | // 代入演算子禁止のため |
MikamiUitOpen | 1:30d9fb51dec1 | 41 | IirDcCut& operator=(const IirDcCut&); |
MikamiUitOpen | 1:30d9fb51dec1 | 42 | }; |
MikamiUitOpen | 1:30d9fb51dec1 | 43 | } |
MikamiUitOpen | 1:30d9fb51dec1 | 44 | #endif // IIR_DC_CUT_HPP |