FFT によるスペクトル解析器

Dependencies:   Array_Matrix mbed SerialTxRxIntr UIT_FFT_Real DSP_ADDA

Committer:
MikamiUitOpen
Date:
Fri Jan 08 02:27:46 2021 +0000
Revision:
0:91cc5a03f0ca
1

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 0:91cc5a03f0ca 1 //-----------------------------------------------------
MikamiUitOpen 0:91cc5a03f0ca 2 // 縦続形 IIR フィルタの次数と係数の定義
MikamiUitOpen 0:91cc5a03f0ca 3 //
MikamiUitOpen 0:91cc5a03f0ca 4 // 2020/11/08, Copyright (c) 2020 MIKAMI, Naoki
MikamiUitOpen 0:91cc5a03f0ca 5 //-----------------------------------------------------
MikamiUitOpen 0:91cc5a03f0ca 6
MikamiUitOpen 0:91cc5a03f0ca 7 #include "Biquad.hpp"
MikamiUitOpen 0:91cc5a03f0ca 8
MikamiUitOpen 0:91cc5a03f0ca 9 // FFT アナライザで使うフィルタ
MikamiUitOpen 0:91cc5a03f0ca 10 // 標本化周波数が 100 kHz の場合,5 kHz 以上で
MikamiUitOpen 0:91cc5a03f0ca 11 // 少なくとも 60 dB 減衰させる LPF
MikamiUitOpen 0:91cc5a03f0ca 12
MikamiUitOpen 0:91cc5a03f0ca 13 // 低域通過フィルタ
MikamiUitOpen 0:91cc5a03f0ca 14 // 連立チェビシェフ特性
MikamiUitOpen 0:91cc5a03f0ca 15 // 次数    : 10 次
MikamiUitOpen 0:91cc5a03f0ca 16 // 標本化周波数:100.00 kHz
MikamiUitOpen 0:91cc5a03f0ca 17 // 遮断周波数 : 4.80 kHz
MikamiUitOpen 0:91cc5a03f0ca 18 // 通過域のリップル: 0.50 dB
MikamiUitOpen 0:91cc5a03f0ca 19 // 阻止域の減衰量 :60.00 dB
MikamiUitOpen 0:91cc5a03f0ca 20 const int ORDER1_ = 10;
MikamiUitOpen 0:91cc5a03f0ca 21 const Biquad::Coefs CK1_[] = {
MikamiUitOpen 0:91cc5a03f0ca 22 { 1.824022E+00f, -8.381143E-01f, -9.384721E-01f, 1.0f}, // 1段目
MikamiUitOpen 0:91cc5a03f0ca 23 { 1.856865E+00f, -9.028289E-01f, -1.790351E+00f, 1.0f}, // 2段目
MikamiUitOpen 0:91cc5a03f0ca 24 { 1.884825E+00f, -9.577163E-01f, -1.875764E+00f, 1.0f}, // 3段目
MikamiUitOpen 0:91cc5a03f0ca 25 { 1.898856E+00f, -9.845865E-01f, -1.896090E+00f, 1.0f}, // 4段目
MikamiUitOpen 0:91cc5a03f0ca 26 { 1.905948E+00f, -9.962457E-01f, -1.901699E+00f, 1.0f}}; // 5段目
MikamiUitOpen 0:91cc5a03f0ca 27 const float G01_ = 1.221772E-03f; // 利得定数
MikamiUitOpen 0:91cc5a03f0ca 28
MikamiUitOpen 0:91cc5a03f0ca 29
MikamiUitOpen 0:91cc5a03f0ca 30
MikamiUitOpen 0:91cc5a03f0ca 31 // 白色雑音発生器で使うフィルタ
MikamiUitOpen 0:91cc5a03f0ca 32 // 標本化周波数が 100 kHz の場合,
MikamiUitOpen 0:91cc5a03f0ca 33 // 100/(4π) ≒7.96 kHz 以上で
MikamiUitOpen 0:91cc5a03f0ca 34 // 少なくとも 60 dB 減衰させる LPF
MikamiUitOpen 0:91cc5a03f0ca 35
MikamiUitOpen 0:91cc5a03f0ca 36 // 低域通過フィルタ
MikamiUitOpen 0:91cc5a03f0ca 37 // 連立チェビシェフ特性
MikamiUitOpen 0:91cc5a03f0ca 38 // 次数    : 6 次
MikamiUitOpen 0:91cc5a03f0ca 39 // 標本化周波数:100.00 kHz
MikamiUitOpen 0:91cc5a03f0ca 40 // 遮断周波数 : 5.00 kHz
MikamiUitOpen 0:91cc5a03f0ca 41 // 通過域のリップル: 0.50 dB
MikamiUitOpen 0:91cc5a03f0ca 42 // 阻止域の減衰量 :60.00 dB
MikamiUitOpen 0:91cc5a03f0ca 43 const int ORDER2_ = 6;
MikamiUitOpen 0:91cc5a03f0ca 44 const Biquad::Coefs CK2_[] = {
MikamiUitOpen 0:91cc5a03f0ca 45 { 1.789361E+00f, -8.093387E-01f, -6.031744E-01f, 1.0f}, // 1段目
MikamiUitOpen 0:91cc5a03f0ca 46 { 1.825484E+00f, -8.899602E-01f, -1.690793E+00f, 1.0f}, // 2段目
MikamiUitOpen 0:91cc5a03f0ca 47 { 1.869667E+00f, -9.677499E-01f, -1.803334E+00f, 1.0f}}; // 3段目
MikamiUitOpen 0:91cc5a03f0ca 48 const float G02_ = 1.404132E-03f; // 利得定数