不韋 呂 / Mbed 2 deprecated SDR_FM_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5月号に掲載

Dependencies:   mbed

SDR_Library/IirDcCut.hpp@1:2b596eab04de, 2021-02-04 (annotated)

Committer:
MikamiUitOpen
Date:
Thu Feb 04 09:45:09 2021 +0000
Revision:
1:2b596eab04de
Parent:
0:4037028ba61a 
2

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 0:4037028ba61a 1 //-----------------------------------------------------------------
MikamiUitOpen 0:4037028ba61a 2 // 直流分除去用 IIR フィルタ
MikamiUitOpen 0:4037028ba61a 3 // u[n] = a1*u[n-1] + x[n]
MikamiUitOpen 0:4037028ba61a 4 // y[n] = g0*(u[n] - u[n-1])
MikamiUitOpen 0:4037028ba61a 5 //
MikamiUitOpen 0:4037028ba61a 6 // 2020/08/17, Copyright (c) 2020 MIKAMI, Naoki
MikamiUitOpen 0:4037028ba61a 7 //-----------------------------------------------------------------
MikamiUitOpen 0:4037028ba61a 8
MikamiUitOpen 0:4037028ba61a 9 #include "mbed.h"
MikamiUitOpen 0:4037028ba61a 10
MikamiUitOpen 0:4037028ba61a 11 #ifndef IIR_DC_CUT_HPP
MikamiUitOpen 0:4037028ba61a 12 #define IIR_DC_CUT_HPP
MikamiUitOpen 0:4037028ba61a 13 namespace Mikami
MikamiUitOpen 0:4037028ba61a 14 {
MikamiUitOpen 0:4037028ba61a 15 class IirDcCut
MikamiUitOpen 0:4037028ba61a 16 {
MikamiUitOpen 0:4037028ba61a 17 public:
MikamiUitOpen 0:4037028ba61a 18 // コンストラクタ
MikamiUitOpen 0:4037028ba61a 19 // a1 フィルタの係数
MikamiUitOpen 0:4037028ba61a 20 // g0 利得定数
MikamiUitOpen 0:4037028ba61a 21 IirDcCut(float a1, float g0)
MikamiUitOpen 0:4037028ba61a 22 : A1_(a1), G0_(g0), un1_(0) {}
MikamiUitOpen 0:4037028ba61a 23
MikamiUitOpen 0:4037028ba61a 24 // フィルタの実行
MikamiUitOpen 0:4037028ba61a 25 float Execute(float xn)
MikamiUitOpen 0:4037028ba61a 26 {
MikamiUitOpen 0:4037028ba61a 27 float un = A1_*un1_ + xn;
MikamiUitOpen 0:4037028ba61a 28 float yn = (un - un1_)*G0_;
MikamiUitOpen 0:4037028ba61a 29 un1_ = un;
MikamiUitOpen 0:4037028ba61a 30 return yn;
MikamiUitOpen 0:4037028ba61a 31 }
MikamiUitOpen 0:4037028ba61a 32
MikamiUitOpen 0:4037028ba61a 33 private:
MikamiUitOpen 0:4037028ba61a 34 const float A1_; // フィルタ係数
MikamiUitOpen 0:4037028ba61a 35 const float G0_; // 利得定数
MikamiUitOpen 0:4037028ba61a 36 float un1_; // 遅延器の値
MikamiUitOpen 0:4037028ba61a 37
MikamiUitOpen 0:4037028ba61a 38 // コピー･コンストラクタ，代入演算子の禁止のため
MikamiUitOpen 0:4037028ba61a 39 IirDcCut(const IirDcCut&);
MikamiUitOpen 0:4037028ba61a 40 IirDcCut& operator=(const IirDcCut&);
MikamiUitOpen 0:4037028ba61a 41 };
MikamiUitOpen 0:4037028ba61a 42 }
MikamiUitOpen 0:4037028ba61a 43 #endif // IIR_DC_CUT_HPP