Lisa Meijer / Mbed 2 deprecated Low_pass_filter

low pass filter

Dependencies:   biquadFilter mbed

main.cpp@0:b86490d955b5, 2016-10-26 (annotated)

Committer:
lisa96m
Date:
Wed Oct 26 14:13:52 2016 +0000
Revision:
0:b86490d955b5
low pass filter;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
lisa96m 0:b86490d955b5 1 #include "mbed.h"
lisa96m 0:b86490d955b5 2 #include "BiQuad.h"
lisa96m 0:b86490d955b5 3
lisa96m 0:b86490d955b5 4 const int Fs = 1250; //Sample Frequency
lisa96m 0:b86490d955b5 5
lisa96m 0:b86490d955b5 6 // Laag doorlaatfilter - butterworth (cutoff van 4Hz)
lisa96m 0:b86490d955b5 7 const double b0 = 1.0;
lisa96m 0:b86490d955b5 8 const double b1 = -1.9858;
lisa96m 0:b86490d955b5 9 const double b2 = 0.9859;
lisa96m 0:b86490d955b5 10 const double a0 = 0.2509E-4;
lisa96m 0:b86490d955b5 11 const double a1 = 0.5018;
lisa96m 0:b86490d955b5 12 const double a2 = 0.2509;
lisa96m 0:b86490d955b5 13
lisa96m 0:b86490d955b5 14 BiQuad lowpass(b0,b1, b2, a0, a1, a2);
lisa96m 0:b86490d955b5 15
lisa96m 0:b86490d955b5 16 // voor bepaald ingangssignaal u1 en output y1
lisa96m 0:b86490d955b5 17 double u1; double y1;
lisa96m 0:b86490d955b5 18
lisa96m 0:b86490d955b5 19 void filter_1()
lisa96m 0:b86490d955b5 20 {
lisa96m 0:b86490d955b5 21 y1 = u1 - mean(u1); //offset?
lisa96m 0:b86490d955b5 22 y1 = fabs(y1);
lisa96m 0:b86490d955b5 23 y1 = lowpass.step(y1)
lisa96m 0:b86490d955b5 24 }