不韋 呂 / Mbed 2 deprecated UIT2_FrequencyShifter

Frequency shifter using analytic signal for ST Nucleo F401RE.

Dependencies:   UITDSP_ADDA mbed

Biquad.hpp@4:04bb0cfea187, 2015-07-25 (annotated)

Committer:
MikamiUitOpen
Date:
Sat Jul 25 07:32:50 2015 +0000
Revision:
4:04bb0cfea187
Parent:
0:4269710caf90 
5

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MikamiUitOpen 0:4269710caf90 1 //--------------------------------------------------------------
MikamiUitOpen 0:4269710caf90 2 // Biquad filter for IIR filter of cascade structure
MikamiUitOpen 0:4269710caf90 3 // 2014/10/21, Copyright (c) 2014 MIKAMI, Naoki
MikamiUitOpen 0:4269710caf90 4 //--------------------------------------------------------------
MikamiUitOpen 0:4269710caf90 5
MikamiUitOpen 0:4269710caf90 6 #ifndef IIR_BIQUAD_HPP
MikamiUitOpen 0:4269710caf90 7 #define IIR_BIQUAD_HPP
MikamiUitOpen 0:4269710caf90 8
MikamiUitOpen 0:4269710caf90 9 #include "mbed.h"
MikamiUitOpen 0:4269710caf90 10
MikamiUitOpen 0:4269710caf90 11 // 2nd order IIR filter
MikamiUitOpen 0:4269710caf90 12 class Biquad
MikamiUitOpen 0:4269710caf90 13 {
MikamiUitOpen 0:4269710caf90 14 public:
MikamiUitOpen 0:4269710caf90 15 struct Coefs { float a1, a2, b1, b2; };
MikamiUitOpen 0:4269710caf90 16
MikamiUitOpen 0:4269710caf90 17 Biquad() {} // Default constructore
MikamiUitOpen 0:4269710caf90 18
MikamiUitOpen 0:4269710caf90 19 Biquad(const Coefs ck)
MikamiUitOpen 0:4269710caf90 20 : a1_(ck.a1), a2_(ck.a2), b1_(ck.b1), b2_(ck.b2)
MikamiUitOpen 0:4269710caf90 21 { Clear(); }
MikamiUitOpen 0:4269710caf90 22
MikamiUitOpen 0:4269710caf90 23 float Execute(float xn)
MikamiUitOpen 0:4269710caf90 24 {
MikamiUitOpen 0:4269710caf90 25 float un = xn + a1_*un1_ + a2_*un2_;
MikamiUitOpen 0:4269710caf90 26 float yn = un + b1_*un1_ + b2_*un2_;
MikamiUitOpen 0:4269710caf90 27
MikamiUitOpen 0:4269710caf90 28 un2_ = un1_;
MikamiUitOpen 0:4269710caf90 29 un1_ = un;
MikamiUitOpen 0:4269710caf90 30
MikamiUitOpen 0:4269710caf90 31 return yn;
MikamiUitOpen 0:4269710caf90 32 }
MikamiUitOpen 0:4269710caf90 33
MikamiUitOpen 0:4269710caf90 34 void Clear() { un1_ = un2_ = 0; }
MikamiUitOpen 0:4269710caf90 35
MikamiUitOpen 0:4269710caf90 36 private:
MikamiUitOpen 0:4269710caf90 37 float a1_, a2_, b1_, b2_;
MikamiUitOpen 0:4269710caf90 38 float un1_, un2_;
MikamiUitOpen 0:4269710caf90 39
MikamiUitOpen 0:4269710caf90 40 Biquad(const Biquad&);
MikamiUitOpen 0:4269710caf90 41 };
MikamiUitOpen 0:4269710caf90 42
MikamiUitOpen 0:4269710caf90 43 #endif // IIR_BIQUAD_HPP
MikamiUitOpen 0:4269710caf90 44