不韋 呂
/
SDR_FM_Tx
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5月号に掲載
SDR_Library/QuadOscIir.hpp@1:32d6e3f7df30, 2021-03-03 (annotated)
- Committer:
- MikamiUitOpen
- Date:
- Wed Mar 03 01:20:09 2021 +0000
- Revision:
- 1:32d6e3f7df30
- Parent:
- 0:7a653530c8ce
2
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
MikamiUitOpen | 0:7a653530c8ce | 1 | //-------------------------------------------------------------- |
MikamiUitOpen | 0:7a653530c8ce | 2 | // IIR フィルタを利用する直交信号発生器のクラス |
MikamiUitOpen | 0:7a653530c8ce | 3 | // |
MikamiUitOpen | 0:7a653530c8ce | 4 | // 2020/07/30, Copyright (c) 2020 MIKAMI, Naoki |
MikamiUitOpen | 0:7a653530c8ce | 5 | //-------------------------------------------------------------- |
MikamiUitOpen | 0:7a653530c8ce | 6 | |
MikamiUitOpen | 0:7a653530c8ce | 7 | #include "mbed.h" |
MikamiUitOpen | 0:7a653530c8ce | 8 | |
MikamiUitOpen | 0:7a653530c8ce | 9 | #ifndef QUAD_PHASE_OSC_IIR_HPP |
MikamiUitOpen | 0:7a653530c8ce | 10 | #define QUAD_PHASE_OSC_IIR_HPP |
MikamiUitOpen | 0:7a653530c8ce | 11 | |
MikamiUitOpen | 0:7a653530c8ce | 12 | namespace Mikami |
MikamiUitOpen | 0:7a653530c8ce | 13 | { |
MikamiUitOpen | 0:7a653530c8ce | 14 | class QuadOscIir |
MikamiUitOpen | 0:7a653530c8ce | 15 | { |
MikamiUitOpen | 0:7a653530c8ce | 16 | public: |
MikamiUitOpen | 0:7a653530c8ce | 17 | // コンストラクタ |
MikamiUitOpen | 0:7a653530c8ce | 18 | // f0 周波数,単位:Hz |
MikamiUitOpen | 0:7a653530c8ce | 19 | // ts 標本化間隔,単位:μs |
MikamiUitOpen | 0:7a653530c8ce | 20 | // amp 振幅 |
MikamiUitOpen | 0:7a653530c8ce | 21 | QuadOscIir(float f0, float ts, float amp = 1) |
MikamiUitOpen | 0:7a653530c8ce | 22 | : TS_(ts*1.0E-6f), A0_(amp) { Set(f0); } |
MikamiUitOpen | 0:7a653530c8ce | 23 | |
MikamiUitOpen | 0:7a653530c8ce | 24 | // sin/cos 発生 |
MikamiUitOpen | 0:7a653530c8ce | 25 | void Generate(float &sinX, float &cosX) |
MikamiUitOpen | 0:7a653530c8ce | 26 | { |
MikamiUitOpen | 0:7a653530c8ce | 27 | float vn = a1_*vn1_ - vn2_; |
MikamiUitOpen | 0:7a653530c8ce | 28 | sinX = b1S_*vn1_; |
MikamiUitOpen | 0:7a653530c8ce | 29 | cosX = A0_*vn + b1C_*vn1_; |
MikamiUitOpen | 0:7a653530c8ce | 30 | |
MikamiUitOpen | 0:7a653530c8ce | 31 | vn2_ = vn1_; // v[n-2] ← v[n-1] |
MikamiUitOpen | 0:7a653530c8ce | 32 | vn1_ = vn; // v[n-1] ← v[n] |
MikamiUitOpen | 0:7a653530c8ce | 33 | } |
MikamiUitOpen | 0:7a653530c8ce | 34 | |
MikamiUitOpen | 0:7a653530c8ce | 35 | // 出力周波数の設定,周波数を変更し再スタートする場合も使える |
MikamiUitOpen | 0:7a653530c8ce | 36 | // f0:周波数,単位:Hz |
MikamiUitOpen | 0:7a653530c8ce | 37 | void Set(float f0) |
MikamiUitOpen | 0:7a653530c8ce | 38 | { |
MikamiUitOpen | 0:7a653530c8ce | 39 | static const float PI2 = 6.283185f; |
MikamiUitOpen | 0:7a653530c8ce | 40 | a1_ = 2.0f*cosf(PI2*f0*TS_); |
MikamiUitOpen | 0:7a653530c8ce | 41 | b1S_ = A0_*sinf(PI2*f0*TS_); |
MikamiUitOpen | 0:7a653530c8ce | 42 | b1C_ = -A0_*cosf(PI2*f0*TS_); |
MikamiUitOpen | 0:7a653530c8ce | 43 | vn1_ = 1.0f; |
MikamiUitOpen | 0:7a653530c8ce | 44 | vn2_ = 0.0f; |
MikamiUitOpen | 0:7a653530c8ce | 45 | } |
MikamiUitOpen | 0:7a653530c8ce | 46 | |
MikamiUitOpen | 0:7a653530c8ce | 47 | private: |
MikamiUitOpen | 0:7a653530c8ce | 48 | const float TS_; // 標本化間隔 |
MikamiUitOpen | 0:7a653530c8ce | 49 | const float A0_; // 振幅 |
MikamiUitOpen | 0:7a653530c8ce | 50 | float a1_, b1S_, b1C_; |
MikamiUitOpen | 0:7a653530c8ce | 51 | float vn1_, vn2_; |
MikamiUitOpen | 0:7a653530c8ce | 52 | |
MikamiUitOpen | 0:7a653530c8ce | 53 | // コピー・コンストラクタ,代入演算子の禁止のため |
MikamiUitOpen | 0:7a653530c8ce | 54 | QuadOscIir(const QuadOscIir&); |
MikamiUitOpen | 0:7a653530c8ce | 55 | QuadOscIir& operator=(const QuadOscIir&); |
MikamiUitOpen | 0:7a653530c8ce | 56 | }; |
MikamiUitOpen | 0:7a653530c8ce | 57 | } |
MikamiUitOpen | 0:7a653530c8ce | 58 | #endif // QUAD_PHASE_OSC_IIR_HPP |