Commit Graph

2 Commits (b734d700210dcd9472852f05154855ef7c7d84b1)

Author SHA1 Message Date
Erik Andresen a152ff546c hrmmar: bthrm compatibility
- Disable when bthrm is active
- Enable fft elim as default
2023-03-19 08:26:51 +01:00
Erik Andresen 77e270d356 hrmmar: Add fft elimination algorithm to remove MA
The fft with size=256 is calculated over a window of 8 seconds with step size 2
seconds. Sample rate of acceleration (12.5Hz) and PPG sensor (25Hz) is unchanged, so the algorithm runs with 12.5Hz.
Generally the maximum peak in fft spectrum in an interval of -5..+10BPM of
last one is used.

The low fft resolution limits the accuracy to ~3BPM, but mean error
is ~5-10BPM.

If firmware reports confidence >= 90% its value is used.
2022-11-27 19:05:40 +01:00