FFT for real data using decimation-in-frequency algorithm. 実データに対するFFT.周波数間引きアルゴリズムを使用. このライブラリを登録した際のプログラム: Demo_FFT_IFFT
Dependents: UIT2_SpectrumAnalyzer F746_SpectralAnalysis_NoPhoto F746_FFT_Speed F746_RealtimeSpectrumAnalyzer ... more
fftReal.hpp@3:dc123081d491, 2020-01-13 (annotated)
- Committer:
- MikamiUitOpen
- Date:
- Mon Jan 13 08:54:18 2020 +0000
- Revision:
- 3:dc123081d491
- Parent:
- 2:9649d0e2bb4a
- Child:
- 4:0b4975fffc90
4
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
MikamiUitOpen | 0:982a9acf3a07 | 1 | //------------------------------------------------------------------- |
MikamiUitOpen | 3:dc123081d491 | 2 | // データが実数の場合の FFT class(ヘッダ) |
MikamiUitOpen | 3:dc123081d491 | 3 | // |
MikamiUitOpen | 3:dc123081d491 | 4 | // 2020/01/13, Copyright (c) 2020 MIKAMI, Naoki |
MikamiUitOpen | 0:982a9acf3a07 | 5 | //------------------------------------------------------------------- |
MikamiUitOpen | 0:982a9acf3a07 | 6 | |
MikamiUitOpen | 0:982a9acf3a07 | 7 | #ifndef FFT_REAL_HPP |
MikamiUitOpen | 0:982a9acf3a07 | 8 | #define FFT_REAL_HPP |
MikamiUitOpen | 0:982a9acf3a07 | 9 | |
MikamiUitOpen | 0:982a9acf3a07 | 10 | #include "mbed.h" |
MikamiUitOpen | 3:dc123081d491 | 11 | #include <complex> // complex で使用 |
MikamiUitOpen | 3:dc123081d491 | 12 | #include "Array.hpp" // "Array_Matrix" という名前で Mbed に登録 |
MikamiUitOpen | 0:982a9acf3a07 | 13 | |
MikamiUitOpen | 0:982a9acf3a07 | 14 | namespace Mikami |
MikamiUitOpen | 0:982a9acf3a07 | 15 | { |
MikamiUitOpen | 0:982a9acf3a07 | 16 | typedef complex<float> Complex; // define "Complex" |
MikamiUitOpen | 0:982a9acf3a07 | 17 | |
MikamiUitOpen | 0:982a9acf3a07 | 18 | class FftReal |
MikamiUitOpen | 0:982a9acf3a07 | 19 | { |
MikamiUitOpen | 2:9649d0e2bb4a | 20 | public: |
MikamiUitOpen | 3:dc123081d491 | 21 | // コンストラクタ |
MikamiUitOpen | 2:9649d0e2bb4a | 22 | explicit FftReal(int16_t n); |
MikamiUitOpen | 3:dc123081d491 | 23 | // FFT の実行 |
MikamiUitOpen | 2:9649d0e2bb4a | 24 | void Execute(const float x[], Complex y[]); |
MikamiUitOpen | 3:dc123081d491 | 25 | // IFFT の実行 |
MikamiUitOpen | 2:9649d0e2bb4a | 26 | void ExecuteIfft(const Complex y[], float x[]); |
MikamiUitOpen | 2:9649d0e2bb4a | 27 | |
MikamiUitOpen | 0:982a9acf3a07 | 28 | private: |
MikamiUitOpen | 0:982a9acf3a07 | 29 | const int N_FFT_; |
MikamiUitOpen | 0:982a9acf3a07 | 30 | const float N_INV_; |
MikamiUitOpen | 3:dc123081d491 | 31 | Array<Complex> wTable_; // 回転子 |
MikamiUitOpen | 3:dc123081d491 | 32 | Array<uint16_t> bTable_; // ビット逆順 |
MikamiUitOpen | 3:dc123081d491 | 33 | Array<Complex> u_; // 作業領域 |
MikamiUitOpen | 0:982a9acf3a07 | 34 | |
MikamiUitOpen | 3:dc123081d491 | 35 | // 最終ステージを除いた処理 |
MikamiUitOpen | 1:559a63853f3f | 36 | void ExcludeLastStage(); |
MikamiUitOpen | 3:dc123081d491 | 37 | // IFFT の美と逆順の並べ替えで使用 |
MikamiUitOpen | 0:982a9acf3a07 | 38 | int Index(int n) { return (N_FFT_-bTable_[n]); } |
MikamiUitOpen | 0:982a9acf3a07 | 39 | |
MikamiUitOpen | 3:dc123081d491 | 40 | // コピー・コンストラクタおよび代入演算子の禁止のため |
MikamiUitOpen | 0:982a9acf3a07 | 41 | FftReal(const FftReal& ); |
MikamiUitOpen | 0:982a9acf3a07 | 42 | FftReal& operator=(const FftReal& ); |
MikamiUitOpen | 0:982a9acf3a07 | 43 | }; |
MikamiUitOpen | 0:982a9acf3a07 | 44 | } |
MikamiUitOpen | 3:dc123081d491 | 45 | #endif // FFT_REAL_HPP |