不韋 呂 / Mbed 2 deprecated UIT2_IIR_Cascade_Biquad

IIR filter of cascade form using Biquad class for ST Nucleo F401RE.

Dependencies:   UITDSP_ADDA mbed

Biquad.hpp@7:ee6c82112718, 2015-09-04 (annotated)

Committer:
MikamiUitOpen
Date:
Fri Sep 04 09:07:38 2015 +0000
Revision:
7:ee6c82112718
Parent:
0:24c904911225 
8

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 0:24c904911225 1 //--------------------------------------------------------------
MikamiUitOpen 0:24c904911225 2 // Biquad filter for IIR filter of cascade structure
MikamiUitOpen 0:24c904911225 3 // 2014/10/21, Copyright (c) 2014 MIKAMI, Naoki
MikamiUitOpen 0:24c904911225 4 //--------------------------------------------------------------
MikamiUitOpen 0:24c904911225 5
MikamiUitOpen 0:24c904911225 6 #ifndef IIR_BIQUAD_HPP
MikamiUitOpen 0:24c904911225 7 #define IIR_BIQUAD_HPP
MikamiUitOpen 0:24c904911225 8
MikamiUitOpen 0:24c904911225 9 #include "mbed.h"
MikamiUitOpen 0:24c904911225 10
MikamiUitOpen 0:24c904911225 11 // 2nd order IIR filter
MikamiUitOpen 0:24c904911225 12 class Biquad
MikamiUitOpen 0:24c904911225 13 {
MikamiUitOpen 0:24c904911225 14 public:
MikamiUitOpen 0:24c904911225 15 struct Coefs { float a1, a2, b1, b2; };
MikamiUitOpen 0:24c904911225 16
MikamiUitOpen 0:24c904911225 17 Biquad() {} // Default constructore
MikamiUitOpen 0:24c904911225 18
MikamiUitOpen 0:24c904911225 19 Biquad(const Coefs ck)
MikamiUitOpen 0:24c904911225 20 : a1_(ck.a1), a2_(ck.a2), b1_(ck.b1), b2_(ck.b2)
MikamiUitOpen 0:24c904911225 21 { Clear(); }
MikamiUitOpen 0:24c904911225 22
MikamiUitOpen 0:24c904911225 23 float Execute(float xn)
MikamiUitOpen 0:24c904911225 24 {
MikamiUitOpen 0:24c904911225 25 float un = xn + a1_*un1_ + a2_*un2_;
MikamiUitOpen 0:24c904911225 26 float yn = un + b1_*un1_ + b2_*un2_;
MikamiUitOpen 0:24c904911225 27
MikamiUitOpen 0:24c904911225 28 un2_ = un1_;
MikamiUitOpen 0:24c904911225 29 un1_ = un;
MikamiUitOpen 0:24c904911225 30
MikamiUitOpen 0:24c904911225 31 return yn;
MikamiUitOpen 0:24c904911225 32 }
MikamiUitOpen 0:24c904911225 33
MikamiUitOpen 0:24c904911225 34 void Clear() { un1_ = un2_ = 0; }
MikamiUitOpen 0:24c904911225 35
MikamiUitOpen 0:24c904911225 36 private:
MikamiUitOpen 0:24c904911225 37 float a1_, a2_, b1_, b2_;
MikamiUitOpen 0:24c904911225 38 float un1_, un2_;
MikamiUitOpen 0:24c904911225 39
MikamiUitOpen 0:24c904911225 40 Biquad(const Biquad&);
MikamiUitOpen 0:24c904911225 41 };
MikamiUitOpen 0:24c904911225 42
MikamiUitOpen 0:24c904911225 43 #endif // IIR_BIQUAD_HPP
MikamiUitOpen 0:24c904911225 44