A convenient, low cost, heart rate monitor. In one embodiment, a digital filter structure (64) includes a low pass filter having a notch at 60 Hz and a bandpass filter which amplifies signals in a frequency range from 10 Hz to 40 Hz and has a notch at 60 Hz. This digital filter has a recursive structure and uses integer coefficients to simplify and speed up the calculations. A four bit microcontroller (70) may implement the digital filter. The output of the digital filter is subject to enhancement signal processing to emphasize QRS complexes indicative of human heartbeats.
展开▼
